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[Datsun 1200 encyclopedia]

Rear Axle

(Difference between revisions)

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Categories: Rear Axle And Rear Suspension | Propeller Shaft And Differential Carrier

Revision as of 01:06, 14 February 2013
ddgonzal (Talk | contribs)
(->Best Ratio)
<- Previous diff
Current revision
ddgonzal (Talk | contribs)
(->Specifications)
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-The Datsun 1200 used a leaf-sprung live axle. The complete assembly (housing, differential, etc) is know as the '''Rear Axle Assembly'''. +The Datsun 1200 used a leaf-sprung [[live axle]]. The complete assembly (housing, differential, etc.) is known as the '''Rear Axle Assembly'''.
-[http://datsun1200.com/modules/myalbum/photo.php?lid=21319 http://datsun1200.com/uploads/thumbs/21319.jpg]+= Terminology =
 +H145 '''Rear Axle Assembly''' is the complete assembly (housing, differential, etc.)
 +<br>{{Album|21319}}
 +{{Diff_Terminology}}
= Overview = = Overview =
1200 cars use an H145 differential in the axle housing. This is a Hitachi design with 145mm ring gear (5.71 inch). It is a lightweight unit suitable to handle the torque from an A12 engine. Light weight is good, remember that heavy parts take more horsepower to accelerate. 1200 cars use an H145 differential in the axle housing. This is a Hitachi design with 145mm ring gear (5.71 inch). It is a lightweight unit suitable to handle the torque from an A12 engine. Light weight is good, remember that heavy parts take more horsepower to accelerate.
 +
 +{{Album|18142}}
 +
 +B10 H145 uses a hand brake cross Rod -- a solid rod (B110 uses hand brake cables)
 +<br>{{Album|8110}}
 +
 +B110 H145 uses hand brake Cables (no rods)
 +<br>{{Album|9390}}
-All Datsun 1200 utes (trucks) used the stronger and bigger rear axle assembly. The housing in beefier as is the [[H165]] differential. The axle tube are larger diameter, but the overall assembly is the same width.+All Datsun 1200 utes (trucks) used the stronger and bigger rear axle assembly. The housing is beefier as is the [[H165]] differential. The axle tube are larger diameter, but the overall assembly is the same width.
H145 vs H165 H145 vs H165
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=1672 http://datsun1200.com/uploads/thumbs/1672.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=18452 http://datsun1200.com/uploads/thumbs/18452.jpg]+<br>{{Album|18452}} {{Album|1672}}
-Some Australian-assembled B110s used a '''Borg Warner Model 60''' rear axle. See main article: [[Borg Warner Differential]].+Sedan vs Coupe: sedans have a shock bracket welded to the axle housing, which coupe housings lack:
 +<br>{{Album|14584}}
 + 
 +== Borg Warner Model 60 ==
 +Australian-assembled B110 sedans used a Borg Warner Model 60 rear axle, starting in Late 1971.
 + 
 + See main article: [[Borg Warner Differential]]
 + 
 +Borg Warner rear axle has an octagonal rear cover. H145 has no rear cover.
 +<br>{{Album|11405}}
 + 
 += Identification =
 + See Main Article: [[Diff ID]]
= Differential = = Differential =
The '''Differential''' is the part in the center of the Rear Axle assembly. Also known as the "Gear carrier assembly", "pumpkin", "center" or "diff head". It has two purposes: 1) reduce the speed ("rear gearing") and 2) equalize power distribution to left and right wheels even when turning corners (differential). The '''Differential''' is the part in the center of the Rear Axle assembly. Also known as the "Gear carrier assembly", "pumpkin", "center" or "diff head". It has two purposes: 1) reduce the speed ("rear gearing") and 2) equalize power distribution to left and right wheels even when turning corners (differential).
 +
 + See main articles: [[H145]] | [[H165]]
The gear reduction is accomplished by the Ring & Pinion gearset a.k.a. (Crown Ring and Pinion (CRP). The differential action is enabled by the spider gears. The gear reduction is accomplished by the Ring & Pinion gearset a.k.a. (Crown Ring and Pinion (CRP). The differential action is enabled by the spider gears.
-See main articles: [[H145]] and [[H165]]+Differential (normal "open" type)
 +<br>{{Photo!|H150.jpg}} {{Photo!|H150-.jpg}}
= Specifications = = Specifications =
Also see: [[Rear Suspension Specifications]] Also see: [[Rear Suspension Specifications]]
-* 3.90:1 ratio - sedans and coupes+ * 3.90:1 ratio - sedans and coupes
-* 4.11:1 ratio - [[VB110]] wagons with aluminum gear case+ * 4.11:1 ratio - [[VB110]] wagons with aluminum gear case
-* 4.11:1 ratio - [[B120]] Truck [[H165]]+ * 4.11:1 ratio - [[B120]] Truck [[H165]]
-* Ring gear diameter: 145mm (5.71 inch)+ * Ring gear diameter: 145mm (5.71 inch)
-* Torque Rating: about 100 lb. ft.+ * Torque Rating: about 100 lb. ft.
-* Axle assembly width: 1305 mm drum-to-drum+
-Weight+== Width ==
-* [[H145]]: 42kg+{{See|Diff Widths}}
-* [[H165]]: 52kg+ 
 + Datsun 1200 B110/B120
 + * 1305 mm (51.38 in) drum-to-drum
 + * 1295 mm (50.98") axle flange-to-flange
 + * 1185 mm banjo housing w/o backing plates, axles or drums
 + 
 +== Weight ==
 + gear carrier (diff head/pumpkin) with gears & diff
 + * H145 12kg
 + * H150 14kg
 + * H165 18kg
 + 
 + rear axle assembly (housing, brakes, etc)
 + * [[H145]]: 42kg
 + * [[H165]]: 52kg
 + * [[H190]]: 60kg
 + * [[BW78]]: 64kg
 + 
 +== Strength==
 + 
 + See main article: [[Rear_Axle_Swaps#Strength_of_Differential_--_Torque_Rating|Strength of Differential]]
== Best Ratio == == Best Ratio ==
-1200 sedans and coupe come with 3.90 ratio. This is the best all-around ratio for the stock-diameter tires, balancing enough torque for take-off with increased fuel-economy. Top speed is 90 mph with the 3.90 ratio.+1200 sedans and coupe come with 3.90 ratio. This is the best all-around ratio for the stock-diameter tires, balancing enough torque for take-off with increased fuel-economy. Top speed is 90 mph with the 3.90 ratio and is HP limited. Fitting a higher gear (such as 3.70) will lower top speed as the engine won't be able to reach peak power. However, 3.70 will return increased fuel economy.
The Datsun 1200 truck comes with a 4.11 ratio for extra torque taking off and pulling loads up hills. This is excellent for acceleration, but lower fuel economy. It doesn't make the engine rev too high -- rest assured, the A12 engine can run at 110 kph all day long even with the 4.11 gears. Top speed is 85 mph with the 4.11 ratio. The Datsun 1200 truck comes with a 4.11 ratio for extra torque taking off and pulling loads up hills. This is excellent for acceleration, but lower fuel economy. It doesn't make the engine rev too high -- rest assured, the A12 engine can run at 110 kph all day long even with the 4.11 gears. Top speed is 85 mph with the 4.11 ratio.
-Or you can change the gears. Read this discussion: [http://datsun1200.com/modules/myalbum/photo.php?lid=3010 starting at Post 11].+Or you can change the gears. Read this discussion: {{AlbumComment!|3010|8384|I was just gonna ask about the diff ratio}}. The Datsun 1200 Ute/Pickup uses the [[H165]] diff with 4.11 gearset. See [[H165]] for more information about available ratios and the donor cars you'll find them in.
-The Ute uses the [[H165]] gears. See [[H165]] for more information about ratios and donor cars.+ 4.11 3.90 3.70
 + Acceleration: Quicker Normal Slowest
 + Fuel Economy: Worse Better Best
 + Noise: Noisier Noisy Less Noisy
 + Top Speed: lower highest lower
 + 
 +'''QUESTION''': won't lower gear (e.g. 4.11) make you have to shift sooner than with a higher gear like 3.9?
 + 
 +'''ANSWER''': Yes, that's the point - it accelerates faster, so shifts can be done sooner. 4.1 will take off quicker, pull hills from a stop more easily, and haul heavy loads with less engine strain. But it comes with downsides on the top end (3.9 = 90mph, 4.11 = 80 mph).
 + 
 +For the 90% of us that want more leisurely driving, some middling gear ratio is more comfortable. Stay longer in each gear. It's all a tradeoff - quicker but noisier? Quieter but slower? More top speed but slow acceleration? More acceleration but lower top speed? With the 4.1 gearing it will top out about 80 mph with the stock 12" tire diameter.
 + 
 + 
 +'''QUESTION''': What gearing is best for racing?
 + 
 +'''ANSWER''': It depends on what kind of racing. For a detailed consideration of types and conditions, see [http://datsun1200.com/modules/newbb/viewtopic.php?post_id=429792#forumpost429792 jmac's comprehensive answer]
= Maintenance = = Maintenance =
The stock Datsun 1200 differential is a reliable, long lasting part behind an A12 or A13 engine. The ute version is strong enough for 1.8 liter engines. The stock Datsun 1200 differential is a reliable, long lasting part behind an A12 or A13 engine. The ute version is strong enough for 1.8 liter engines.
-# As long as it doesn't run dry on gear lube it will usually last forever. So check it every few months for signs of leaking.+* As long as it doesn't run dry on gear lube it will usually last forever. So check it every few months for signs of leaking.
-# The only common maintenance is to pack the rear wheel bearings every two years or so. This will also keep the bearings quiet and reduce gear lube leakage into the brake area.+* The only common maintenance is to pack the rear wheel bearings every two years or so. This will also keep the bearings quiet and reduce gear lube leakage into the brake area.
 + 
 += Troubleshooting =
 + See [[Differential Service]]
= Differential Lubricant = = Differential Lubricant =
Since the differential is a typical hypoid-gear unit, you can use any lubricant designed for such: Since the differential is a typical hypoid-gear unit, you can use any lubricant designed for such:
-* the traditional "90 weight" gear oil+ * the traditional "90 weight" gear oil
-* the newer 75W-140 or 85W-140 multi-weight gear oil+ * Better: 75W-90 multiweight
 + * Best: the newer 75W-140 or 85W-140 multi-weight gear oil
-For maximum fuel economy, use a modern multi-weight gear oil. Otherwise use this chart to select a single-weight oil:+For maximum fuel economy, use a modern multi-weight gear oil. Otherwise use this Nissan chart to select a single-weight oil:
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=22187 http://datsun1200.com/uploads/thumbs/22187.jpg]+<br>{{Album|22187}}
1972 Nissan Specification 1972 Nissan Specification
Line 70: Line 134:
* Texaco Universal Gear Lub. EP 80,90,140 * Texaco Universal Gear Lub. EP 80,90,140
-<blockquote><table border=1 width=66% cellspacing=0><tr><td><center>+{{OwnersManual|23||Recommended Lubricants}}
-1972 USA [[Owners manual]] (Page 23)<br>+
-[http://s297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/owners_manual/1972/00_cover.jpg http://s297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/owners_manual/1972/th_00_cover.jpg] [http://s297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/owners_manual/1972/23.jpg http://s297.photobucket.com/albums/mm219/ddgonzal/Datsun%201200/owners_manual/1972/th_23.jpg]</center><blockquote><hr>Recommended Lubricants<hr>+
-</blockquote>+
-</td></tr></table></blockquote>+
== GL-4 vs GL-5 == == GL-4 vs GL-5 ==
The differential can use a GL-4 oil, same as the [[Transmission_Overview#Lubricants|transmission lube]]. The differential can use a GL-4 oil, same as the [[Transmission_Overview#Lubricants|transmission lube]].
-GL-5 is now recommmended for the differential, but should not be used in the gearbox unless it is marked both GL-4 AND GL-5.+GL-5 is now recommmended for the differential, but should not be used in the gearbox. ONLY GL-4 is used in the gearbox. If the fluid is marked both GL-4 AND GL-5 compatible, it is not to be used in Nissan gearboxes.
Nissan 1981 Specification Nissan 1981 Specification
* API GL-5 * API GL-5
-= Borg Warner Model 60 =+== LSD ==
-[[Australian-assembled]] B110s used a Borg Warner Model 60 rear axle, starting in Late 1971.+For differentials equipped with a [[LSD|Limited Slip]] unit, use only gear lubricant designed for LSD. Specifically, that is '''APL-GL5''' gear oil.
- +
-See main article: [[Borg Warner Differential]]+
= Leaf Spring Mounting = = Leaf Spring Mounting =
Line 93: Line 151:
= Swapping = = Swapping =
-Datsun 1200 Coupe, sedan, van, and ute housing are all just slightly different.+Datsun 1200 Coupe, sedan, van, and ute housing are all just slightly different: [http://datsun1200.com/modules/newbb/viewtopic.php?topic_id=38085&forum=1&10 discussion in main forum]
- [http://datsun1200.com/modules/newbb/viewtopic.php?topic_id=38085&forum=1&10 discussion in main forum]+ For information about swapping non-1200 diffs, see [[Rear Axle Swaps]]
Sedan axle housing has no welded-on leaf perches. The others do. Plus other small differences. Sedan axle housing has no welded-on leaf perches. The others do. Plus other small differences.
 +
 +* Ute has larger diameter axle housings, requiring larger u-bolts and spring plates
 +* Ute has [[H165]] diff, which uses a different [[tailshaft]]
 +* Brake line splitter differences
 +
 +== Hand Brake ==
 +Length varies
 + * Ute long body
 + * Ute standard body
 + * Car vs ute?
 + * rhd vs lhd?
 +
 +ute
 +<br>{{Album|21317}}
 +
 +== Brake Line Split ==
 +* Brake line splitter is on right side of RHD coupe & sedan
 +* Brake line splitter is on left side of RHD ute
 +* Brake line splitter is near center of LHD coupe & sedan
 +
 +Flexible Hose (from chassis to rear axle) is the same RHD/LHD. Splitter is the same.
 +
 +If needed, rearrange the brake lines on the diff. The left and right tubes are different lengths, so source the opposite arrangement from the old axle.
 +
 +Weld a bracket to hold the splitter bolt in the appropriate location. Or using a large hose clamp, clamp a bit of steel stock in the appropriate location. Thread the stock to accept the splitter bolt.
 +
 +Ute
 +<br>{{Album|21318}} {{Album|21319}} {{Album|20524}}
 +
 + RHD car
 + 46313-18000 CONNECTOR-3 way brake tube
 + 46290-H1000 ASS'Y-TUBE, rear brake (R.H.) Sedan <> 46290-H5001
 + 46290-H1401 ASS'Y-TUBE, rear brake (R.H.) Van, Coupe > 46290-H1400 (to '73-3)
 + 46201-89918 ASS'Y-HOSE, brake rear (l=330)
 +
 + LHD car
 + 46313-18000 CONNECTOR-3WAY REAR
 + 02463-13200 CONNECTOR-3WAY REAR 46313-18000
 + 46290-H5501 ASSY-TUBE REAR BRAKE RH COUPE 0673- 5 46290-H1001
 + 46290-H7301 ASSY-TUBE REAR BRAKE RH COUPE 0673- 5 46290-H5501
 + 46290-H1000 ASSY-TUBE REAR BRAKE RH SEDAN COUPE <> 46290-H1001
 + 46290-H5001 ASSY-TUBE REAR BRAKE RH SEDAN 0673-0473 5 46290-H1001
 + 46290-H7201 ASSY-TUBE REAR BRAKE RH SEDAN 0673-0473 5 46290-H5001
 + 46310-H5501 ASSY-TUBE REAR BRAKE LH COUPE 0673- 5 46310-H1001
 + 46310-H5001 ASSY-TUBE REAR BRAKE LH SEDAN 0673-0672 5 46290-H1001
 + 46310-H1000 ASSY-TUBE REAR BRAKE LH SEDAN COUPE -473
 + 46310-H1001 ASSY-TUBE REAR BRAKE LH SEDAN COUPE 0573- <> 46310-H1000
 + 46201-89918 ASSY-HOSE BRAKE REAR L=330 <> 46201-H7200
= Pinion Snubber = = Pinion Snubber =
The Torque Arrester (pinion snubber) is a rubber bumper that prevents the differential from rotating too much under torque input. The Torque Arrester (pinion snubber) is a rubber bumper that prevents the differential from rotating too much under torque input.
-[http://datsun1200.com/modules/myalbum/photo.php?lid=24159 http://datsun1200.com/uploads/thumbs/24159.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=24933 http://datsun1200.com/uploads/thumbs/24933.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=24940 http://datsun1200.com/uploads/thumbs/24940.jpg] +{{Album|24159}} {{Album|24933}}
Only used by Sedan and Coupe. Only used by Sedan and Coupe.
55350-H1000 APRESTER-TORQUE REAR SPRING 55350-H1000 APRESTER-TORQUE REAR SPRING
- +<br>{{Upload|174_509b12abdfe7b.jpg}} {{Album|24940}}
-[http://datsun1200.com/uploads/newbb/174_509b12abdfe7b.jpg Torque Arrester]+
-<br><img size=240>http://datsun1200.com/uploads/newbb/174_509b12abdfe7b.jpg</img>+
= Bump Stop = = Bump Stop =
-Coupe, wagon and pickup have bump stops on the top of the axle tube.+{{Album|24932}}
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=24926 http://datsun1200.com/uploads/thumbs/24926.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=24932 http://datsun1200.com/uploads/thumbs/24932.jpg]+
-Sedan has Bump Stops in the Shock absorbers:+ See main article: [[Shock absorbers]]
-<br>[http://datsun1200.com/modules/myalbum/photo.php?lid=2491 http://datsun1200.com/uploads/thumbs/24951.jpg]+ 
-<br>See main article: [[Shock absorbers]]+Sedan has Bump Stops on the Shock absorbers:
 +<br>{{Album|24951}}
 + 
 +Coupe, wagon and pickup have bump stops on the top of the axle tube.
 +<br>{{Album|24926}}
= Axles = = Axles =
Datsun 1200 -- both car H145 and truck H165 -- uses 23-spline axles. The truck axles are a larger diameter and so they do not interchange. Datsun 1200 -- both car H145 and truck H165 -- uses 23-spline axles. The truck axles are a larger diameter and so they do not interchange.
-See main article: [[Axle Shaft]]+ See Main Article: [[Axle Shaft]]
-http://datsun1200.com/uploads/thumbs/5633.jpg+{{Album!|5633}}
= Part Numbers = = Part Numbers =
See the various related articles such as: See the various related articles such as:
-* Axle Shaft+ * [[Axle Shaft]]
-* Differential+ * [[H145]]
-* Leaf Springs+ * [[Leaf Springs]]
-* Rear Suspension+ * [[Rear Suspension]]
-* [[:Category:Rear Axle And Rear Suspension|Rear Axle And Rear Suspension]]+ * [[:Category:Rear Axle And Rear Suspension|Category: Rear Axle And Rear Suspension]]
= Limited Slip = = Limited Slip =
Datsun 1200 was not offered with a limited-slip differential, however Datsun Competition sold an LSD for the H145. This part is NLA, however it may be found occasionally in specialty shops or on eBay. Datsun 1200 was not offered with a limited-slip differential, however Datsun Competition sold an LSD for the H145. This part is NLA, however it may be found occasionally in specialty shops or on eBay.
-See main article: [[LSD|Limited Slip]]+ See Main Article: [[LSD|Limited Slip]]
-[[Category:Rear Axle And Rear Suspension]] 
-[[Category:Propeller Shaft And Differential Carrier]] 
= Rear Axle Removal = = Rear Axle Removal =
To remove the rear axle assembly from the vehicle: To remove the rear axle assembly from the vehicle:
Line 153: Line 258:
# Take out the whole thing and clean it up # Take out the whole thing and clean it up
-= Axle Shaft Removal = +{{Album|21318}}
-Remove the individual axles from the axle housing (main body).+
-# If replacing one side, jack that side up to prevent oil leakage. Otherwise drain the axle housing.+== Axle Shaft Removal ==
 + See main article: [[Axle Shaft]]
-# Unscrew the brake line at the rear of the drum backing plate. Plug the line.+== Axle Bearing Removal ==
 + See main article: [[Axle Shaft]]
-# Remove the brake drum, then remove the four bolts that are at the end of the axle tube. They are accessible via the hole in the axle. These will have nylock nuts on the ends.+== Axle Bearing Installation ==
 + See main article: [[Axle Shaft]]
-# Pull out the axle. This may come out easily or you may have to jiggle the diff where it connects to the tail shaft to loosen the spline. If all else fails the use a slide hammer and connect it to the axle where the wheel lugs are. You can also put the drum on backwards and lightly attach the lugnuts, then use the drum as a slide hammer.+== Axle Shaft Installation ==
 + See main article: [[Axle Shaft]]
-# Remove the seal just inside the axle that sits behind the bearing. Install a new seal upon installation+[[Category:Rear Axle And Rear Suspension]]
- +[[Category:Propeller Shaft And Differential Carrier]]{{End}}
-# Mark the axle on back to indicate which side it came from+
- +
-= Axle Bearing Removal =+
-To replace the bearing, or to replace the brake backing plates from the axle, you will need a coal chisel, an anvil of some description, and a big hammer. +
- +
-# The bearing retaining collar needs to be removed first+
-# Use the coal chisel and or an angle grinder to cut the retaining collar off – be careful not to damage the axle shaft, unless you plan to replace the shaft.+
-# Use a long bearing puller (or chain of pullers) to remove the bearing.+
-# Alternatively, use a grinder to cut the bearing until it can be knocke d off.+
-# After the collar and bearing are removed there will also be a thin washer to remove, it should just slide off and then the backing plate will slide off +
- +
-Keep track of the Shims that go between the bearing and the backing plate. They may differ RH axle vs LH axle+
- +
-Always replace with a new bearing.+
- +
-= Axle Bearing Installation =+
-Once the old axle bearing has been removed:+
- +
-# Slide the 1200 thin washer on the axle the same way it came off+
-# Slide the drum backing plate onto the axle – make sure that it is on the right way (shoe mechanism facing out)+
-# Press the bearing back on to the axle +
-## Either get them done professionally (for the cost of a few dollars it will be done right) +
-## Or get a big pipe/tube of the right diameter of the inner race and bash it on without damaging the wheel lugs or the bearing. +
-## Press the retaining collar on to the axle (as above)+
- +
-= Axle Installation =+
-# After fitting the bearing as above, fit a new seal into the axle housing end.+
-# Put the shim in behind the bearing – don’t bend it too much+
-# Insert the axle into the main body. You will need to line up the spline into the diff centre and gently persuade the axle into place+
-# Tighten the 4 fastening bolts+
-# Reassemble the hand brake shoes and mechanisms+
-# Fill the differential oil+
-# Replace brake hard line+
-# Bleed the wheel cylinder+
- +
-= Photo Index =+
-[http://datsun1200.com/modules/myalbum/photo.php?lid=14584 http://datsun1200.com/uploads/thumbs/14584.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=20524 http://datsun1200.com/uploads/thumbs/20524.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=21317 http://datsun1200.com/uploads/thumbs/21317.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=21318 http://datsun1200.com/uploads/thumbs/21318.jpg] [http://datsun1200.com/modules/myalbum/photo.php?lid=21319 http://datsun1200.com/uploads/thumbs/21319.jpg]+

Current revision

The Datsun 1200 used a leaf-sprung live axle. The complete assembly (housing, differential, etc.) is known as the Rear Axle Assembly.

Contents

Terminology

H145 Rear Axle Assembly is the complete assembly (housing, differential, etc.)
21319.jpgAlbum 21319

Differential: The word "diff" refers to the small gears in the rear end that control the left-to-right wheel speeds
29522.jpgAlbum 29522
38100 SET-HYPOID GEAR & PINION

open type with differential gears visible

Datsun 1200 uses H145 type differential

By popular usage "diff" is also used to refer to these parts:
Gear Carrier Assembly ("diff head" or pumpkin or "center section"), including Ring and Pinion and the carrier these bolt to
25280.jpgAlbum 25280

Or, the entire Rear Axle Assembly including the housing, gears, axles etc.
21319.jpgAlbum 21319

Axle Housing
174_5493cff52ab33.jpgPost 461926

Axle aka axle shaft (includes wheel bearing)
3621.jpgAlbum 3621

Gear Carrier aka "center" (not to be confused with "center section" which is the center with the gears installed)
29523.jpgAlbum 29523

Ring and Pinion (R&P) are the large final-drive gears e.g. the "ratio" gears. Known as "Crown Wheel and Pinion" (CWP) in British English.
29524.jpgAlbum 29524
38100 SET-HYPOID GEAR & PINION

Spider gears: The smaller side gears are known as the "spider gears". These are the ones that actually allow a differential speed.
29525.jpgAlbum 29525
38423 SIDE GEARS
38427 PINION SHAFT
38425 PINION GEARS

LSD: Limited-slip differential. Most designs use a spring-loaded clutch to prevent one wheel from spinning by itself. Instead, the LSD resists spinning but when traction is overcome, both wheels will spin.
13712.jpgAlbum 13712

Overview

1200 cars use an H145 differential in the axle housing. This is a Hitachi design with 145mm ring gear (5.71 inch). It is a lightweight unit suitable to handle the torque from an A12 engine. Light weight is good, remember that heavy parts take more horsepower to accelerate.

18142.jpgAlbum 18142

B10 H145 uses a hand brake cross Rod -- a solid rod (B110 uses hand brake cables)
8110.jpgAlbum 8110

B110 H145 uses hand brake Cables (no rods)
9390.jpgAlbum 9390

All Datsun 1200 utes (trucks) used the stronger and bigger rear axle assembly. The housing is beefier as is the H165 differential. The axle tube are larger diameter, but the overall assembly is the same width.

H145 vs H165
18452.jpgAlbum 18452 1672.jpgAlbum 1672

Sedan vs Coupe: sedans have a shock bracket welded to the axle housing, which coupe housings lack:
14584.jpgAlbum 14584

Borg Warner Model 60

Australian-assembled B110 sedans used a Borg Warner Model 60 rear axle, starting in Late 1971.

See main article: Borg Warner Differential

Borg Warner rear axle has an octagonal rear cover. H145 has no rear cover.
11405.jpgAlbum 11405

Identification

See Main Article: Diff ID

Differential

The Differential is the part in the center of the Rear Axle assembly. Also known as the "Gear carrier assembly", "pumpkin", "center" or "diff head". It has two purposes: 1) reduce the speed ("rear gearing") and 2) equalize power distribution to left and right wheels even when turning corners (differential).

See main articles: H145 | H165

The gear reduction is accomplished by the Ring & Pinion gearset a.k.a. (Crown Ring and Pinion (CRP). The differential action is enabled by the spider gears.

Differential (normal "open" type)
H150.jpg H150-.jpg

Specifications

Also see: Rear Suspension Specifications

* 3.90:1 ratio - sedans and coupes
* 4.11:1 ratio - VB110 wagons with aluminum gear case
* 4.11:1 ratio - B120 Truck H165
* Ring gear diameter: 145mm (5.71 inch)
* Torque Rating: about 100 lb. ft.

Width

See also: Diff Widths
Datsun 1200 B110/B120
* 1305 mm (51.38 in) drum-to-drum
* 1295 mm (50.98") axle flange-to-flange
* 1185 mm banjo housing w/o backing plates, axles or drums

Weight

gear carrier (diff head/pumpkin) with gears & diff
* H145 12kg
* H150 14kg
* H165 18kg
rear axle assembly (housing, brakes, etc)
* H145: 42kg
* H165: 52kg
* H190: 60kg
* BW78: 64kg

Strength

See main article: Strength of Differential

Best Ratio

1200 sedans and coupe come with 3.90 ratio. This is the best all-around ratio for the stock-diameter tires, balancing enough torque for take-off with increased fuel-economy. Top speed is 90 mph with the 3.90 ratio and is HP limited. Fitting a higher gear (such as 3.70) will lower top speed as the engine won't be able to reach peak power. However, 3.70 will return increased fuel economy.

The Datsun 1200 truck comes with a 4.11 ratio for extra torque taking off and pulling loads up hills. This is excellent for acceleration, but lower fuel economy. It doesn't make the engine rev too high -- rest assured, the A12 engine can run at 110 kph all day long even with the 4.11 gears. Top speed is 85 mph with the 4.11 ratio.

Or you can change the gears. Read this discussion: I was just gonna ask about the diff ratio. The Datsun 1200 Ute/Pickup uses the H165 diff with 4.11 gearset. See H165 for more information about available ratios and the donor cars you'll find them in.

              4.11     3.90    3.70
Acceleration: Quicker  Normal  Slowest
Fuel Economy: Worse    Better  Best
Noise:        Noisier  Noisy   Less Noisy
Top Speed:    lower    highest lower

QUESTION: won't lower gear (e.g. 4.11) make you have to shift sooner than with a higher gear like 3.9?

ANSWER: Yes, that's the point - it accelerates faster, so shifts can be done sooner. 4.1 will take off quicker, pull hills from a stop more easily, and haul heavy loads with less engine strain. But it comes with downsides on the top end (3.9 = 90mph, 4.11 = 80 mph).

For the 90% of us that want more leisurely driving, some middling gear ratio is more comfortable. Stay longer in each gear. It's all a tradeoff - quicker but noisier? Quieter but slower? More top speed but slow acceleration? More acceleration but lower top speed? With the 4.1 gearing it will top out about 80 mph with the stock 12" tire diameter.


QUESTION: What gearing is best for racing?

ANSWER: It depends on what kind of racing. For a detailed consideration of types and conditions, see jmac's comprehensive answer

Maintenance

The stock Datsun 1200 differential is a reliable, long lasting part behind an A12 or A13 engine. The ute version is strong enough for 1.8 liter engines.

  • As long as it doesn't run dry on gear lube it will usually last forever. So check it every few months for signs of leaking.
  • The only common maintenance is to pack the rear wheel bearings every two years or so. This will also keep the bearings quiet and reduce gear lube leakage into the brake area.

Troubleshooting

See Differential Service

Differential Lubricant

Since the differential is a typical hypoid-gear unit, you can use any lubricant designed for such:

* the traditional "90 weight" gear oil
* Better: 75W-90 multiweight
* Best: the newer 75W-140 or 85W-140 multi-weight gear oil

For maximum fuel economy, use a modern multi-weight gear oil. Otherwise use this Nissan chart to select a single-weight oil:
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1972 Nissan Specification
* API GL-4 
* MIL-L-2105 
Such as:
* Chevron Multiservice Gear Lub. 75,80,90,140
* Esso Gear Oil GP 80,90,140
* Mobil Mobilube EP or GX 80-90,90,140
* Shell Spirax 75EP,80EP,90EP,140EP
* Sunoco Multipurpose Gear Lub. GL-4 80,90,140
* Texaco Universal Gear Lub. EP 80,90,140

1972 USA Owners manual (Page 23 ... ):

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Recommended Lubricants

GL-4 vs GL-5

The differential can use a GL-4 oil, same as the transmission lube.

GL-5 is now recommmended for the differential, but should not be used in the gearbox. ONLY GL-4 is used in the gearbox. If the fluid is marked both GL-4 AND GL-5 compatible, it is not to be used in Nissan gearboxes.

Nissan 1981 Specification
* API GL-5

LSD

For differentials equipped with a Limited Slip unit, use only gear lubricant designed for LSD. Specifically, that is APL-GL5 gear oil.

Leaf Spring Mounting

Sedan, Coupe, Wagon and Ute (Truck) all have different mounting points. See Leaf Springs

Swapping

Datsun 1200 Coupe, sedan, van, and ute housing are all just slightly different: discussion in main forum

For information about swapping non-1200 diffs, see Rear Axle Swaps

Sedan axle housing has no welded-on leaf perches. The others do. Plus other small differences.

  • Ute has larger diameter axle housings, requiring larger u-bolts and spring plates
  • Ute has H165 diff, which uses a different tailshaft
  • Brake line splitter differences

Hand Brake

Length varies

* Ute long body
* Ute standard body
* Car vs ute?
* rhd vs lhd?

ute
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Brake Line Split

  • Brake line splitter is on right side of RHD coupe & sedan
  • Brake line splitter is on left side of RHD ute
  • Brake line splitter is near center of LHD coupe & sedan

Flexible Hose (from chassis to rear axle) is the same RHD/LHD. Splitter is the same.

If needed, rearrange the brake lines on the diff. The left and right tubes are different lengths, so source the opposite arrangement from the old axle.

Weld a bracket to hold the splitter bolt in the appropriate location. Or using a large hose clamp, clamp a bit of steel stock in the appropriate location. Thread the stock to accept the splitter bolt.

Ute
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RHD car
46313-18000 CONNECTOR-3 way brake tube
46290-H1000 ASS'Y-TUBE, rear brake (R.H.) Sedan <> 46290-H5001
46290-H1401 ASS'Y-TUBE, rear brake (R.H.) Van, Coupe > 46290-H1400 (to '73-3)
46201-89918 ASS'Y-HOSE, brake rear (l=330)
LHD car
46313-18000 CONNECTOR-3WAY REAR
02463-13200 CONNECTOR-3WAY REAR 46313-18000
 46290-H5501 ASSY-TUBE REAR BRAKE RH COUPE 0673- 5 46290-H1001
 46290-H7301 ASSY-TUBE REAR BRAKE RH COUPE 0673- 5 46290-H5501
 46290-H1000 ASSY-TUBE REAR BRAKE RH SEDAN COUPE <> 46290-H1001
 46290-H5001 ASSY-TUBE REAR BRAKE RH SEDAN 0673-0473 5 46290-H1001
 46290-H7201 ASSY-TUBE REAR BRAKE RH SEDAN 0673-0473 5 46290-H5001
46310-H5501 ASSY-TUBE REAR BRAKE LH COUPE 0673- 5 46310-H1001
46310-H5001 ASSY-TUBE REAR BRAKE LH SEDAN 0673-0672 5 46290-H1001
46310-H1000 ASSY-TUBE REAR BRAKE LH SEDAN COUPE -473
46310-H1001 ASSY-TUBE REAR BRAKE LH SEDAN COUPE 0573- <> 46310-H1000
46201-89918 ASSY-HOSE BRAKE REAR L=330 <> 46201-H7200

Pinion Snubber

The Torque Arrester (pinion snubber) is a rubber bumper that prevents the differential from rotating too much under torque input.

24159.jpgAlbum 24159 24933.jpgAlbum 24933

Only used by Sedan and Coupe.

55350-H1000 APRESTER-TORQUE REAR SPRING
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Bump Stop

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See main article: Shock absorbers

Sedan has Bump Stops on the Shock absorbers:
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Coupe, wagon and pickup have bump stops on the top of the axle tube.
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Axles

Datsun 1200 -- both car H145 and truck H165 -- uses 23-spline axles. The truck axles are a larger diameter and so they do not interchange.

See Main Article: Axle Shaft

5633.jpg

Part Numbers

See the various related articles such as:

* Axle Shaft
* H145
* Leaf Springs
* Rear Suspension
* Category: Rear Axle And Rear Suspension

Limited Slip

Datsun 1200 was not offered with a limited-slip differential, however Datsun Competition sold an LSD for the H145. This part is NLA, however it may be found occasionally in specialty shops or on eBay.

See Main Article: Limited Slip

Rear Axle Removal

To remove the rear axle assembly from the vehicle:

  1. Disengage from tail shaft
  2. Disengage hand brake cable from the adjustment block near the front of the diff
  3. Drain the diff oil
  4. Disengage the brake line which is in front of the diff
  5. Remove drums
  6. Remove the handbrake cable by taking out the pins at the ends
  7. Remove the U-bolts that hold the axle main body to the springs
  8. Take out the whole thing and clean it up

21318.jpgAlbum 21318

Axle Shaft Removal

See main article: Axle Shaft

Axle Bearing Removal

See main article: Axle Shaft

Axle Bearing Installation

See main article: Axle Shaft

Axle Shaft Installation

See main article: Axle Shaft 
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