my dads 120y work car has a biger diff then my 1200 coupe

Australian-assembled B210s got a Borg-Warner model 68 rear axle assembly.

it is jap 120y

Pre 1976 120Y's had the small japanese diff unit but the post 1976 ones had a Borg Warner diff related to the ones out of corrolas and coronas. just have a look to see if the diff has a backing plate with bolts it's a B/W. if it has a hat on the front then it will be a jap one

I have 3 120Y's

basically, Aussie 120Y's (like "The Defect") had the model 68 BW diff

the remains of te EX neigbors's 120Y junior stocky has a "CIG improved" BW diff!

Jap 120Y's has the H145 (the parts car has one of these) if the diff in "The Defect" fails I'll put the "CIG improved" one in, as my driving style would probably kill the H145 in no time!

the tail shaft will be 2inchs too long i think and the suspension bolts are 9mm instead of 13mm like on a datsun 1200 diff, apart from that, bolt in job. just need to mod the tail shaft and shaft plate to diff from tial shaft

Japanese B210s have the H150, which looks just like the H145 but it significantly stronger.

My USA issue Datsun factory shop manual says all '77's had an H150 diff. 3.70 for manual, and 3.89 to auto.

120Ys in Aus all had 3.89 ratio (but I've never looked under a 120Y Van or wagon - maybe they got a 4.1. Anyone got an Aussie workshop manual?)

The coupes were fully imported, and all had the Jap diff. Sedans were assembled here and every single one I have seen has a BorgWarner. These are a pretty strong diff - certainly up to the job for any A series. I still use one in my L18 coupe with 146bhp at the wheels. But I use the wider Corolla unit for increased track and they have 3.89, 4.1, and 4.3 ratios available. Only ever broke 2 axles, but they've both been caused by axle tramp problems.

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no, you just need the tailshaft, u-bolts and plates from the donor car. No mods required at all.

Cable_Ties post jogged my memory - If you're putting the 120Y sedan BW diff in a 1200 coupe, you also need to get 120Y coupe base plates for the spring shackles as they incorporate the lower shock mount - the sedans don't have that - their shock mounts on top of the diff. Brake lines and handbrake cable matches up fine from 120Y sedan to 1200 coupe - must be a difference in the ute diff.

I've got a ute diff in a 120Y sedan that will be pulled shortly. 4.1 ratio. Bolt in affair, well it is now. Brake lines on opposite side, shock mounts different, although coupe, wagon and van are different again.


And yes I believe the panel van diff is a 4.1