Well today another went bang. The one 2weeks ago just ground but this one blew to pieces. Well anyway at the moment im just going to get a h145 centre and put in. But what I would like to know what whole rear axle assembly will bolt straight up into the sedan. I ask this because I went to put a whole assembly out of a 1200 coupe into the sedan but the mounting feet were different as the coupe one didn't have anywhere to mount the shocks.

What I would like to know is if a 120y whole rear axle assembly will fit no troubles or will I have to get the sedan mounts welded on to the 120y housing. Also is this the same for the h165 or did it have straight up and down shocks like the sedan. I ask this because a ute diff is coming soon to the little sedan.

Cheers
Daniel

its just a case of swapping the shock mounting plate over as it is not welded to the diff

the ute diff is the go, but remember you will need a ute tailshaft or custom to put it in, aswell as ute u bolts, or hunt at the wreckers for u bolts that will work (bluey or vanette etc.)

the 120y diffs are not a straight swap and you would need to change mounts (there is 2 types of 120y diff also so beware, borg warner and h-series, im pretty sure the h-series is not a straight swap, borg warner is definately not),


your post confuses me a bit hope im answerin the right questions...

bollocks!

The complete 120Y diffs (drum to drum) DO bolt straight in. The BorgWarner 120Y diff is the go. Hundreds of dollars cheaper than the H165, and probably bigger and stronger, but I haven't bothered measuring them. Just get the 120Y tailshaft as well, because the flanges are different. And the handbrake cable up to the adjuster.

The BorgWarners are found in the 120Y sedans, and have the same kind of shock mounting on top of the diff as the 1200 sedan does. The H150 jap diff is in the fully imported 120Y coupes - don't bother with that.

if you have Stanza struts in the front, a wider housing is available to equalise the track, in the same BorgWarner series diff out of 70's Corollas - love those local content laws . The corolla also has 3.9, 4.1 and 4.3 ratios, whereas the 120Y is only in 3.9. Corolla diffs use a different handbrake arrangement though, so some work would be required there, and you'll need the 120Y tailshaft and diff flange.

The ute diff mounts the shocks the same as a coupe - off the leafspring shackle.
Sedan the shock is mounted off the leafspring mount on the diff.
So to fit a ute diff one would need to make a new shock mount and somehow attach it to the diff.

Thaks guys. You aswered all the questions. Just to double check if I get a borkwarner out of a 120y sedan including tailshaft and u-bolts it will bolt straight in no rewelding required. This sounds good because I know a wrecker near me with over 12 120ys in a row. One must have a borgwar.ner

maybe i am getting confused between the diffrences between a coupe and sedan 1200 here

but when i checked out a borg warner there was no way it was going to lacate itself on the springs in a coupe, maybe thats not a problem for the sedans though as the shock mount in a sedan may compensate for the diffrence in locating hole size

can clear that up for me?

The 120Y rear axle assembly will be found ONLY in Australian built sedans from July '76. The ratio is 3.889 to 1 & all other models were imported, so they will have the H150 diferential. The 120Y coupe uses the same shocks as the 1200 coupe, so if you wanted to use the H150 diff in a 1200 coupe, then see if you can use a 120Y coup rear end, or just swap the diff center into your housing, with the correct spacer to align the side gears with the axles.

The 120Y warner rear axle assembly should be a relatively easy swap into a 1200 sedan,.... i think, but to use this axle under a coupe will need more work.

Have you thought about giving it a bit less stick untill you sort out this rear end problem? It might save another tow home.

but the rear end problem can be sorted out in one afternoon with the 120Y diff swap! You'll never have to worry about it again with an A series engine.

I haven't seen a 120Y sedan that wasn't Aus built with the BorgWarner diff. If they exist in Aus, they are extremely uncommon.

I'm dreadfully sorry for misrepresenting the ratio as 3.9 IF it is actually 3.889:1. I seem to remember them having 10 pinion teeth, but I might be getting mixed up with the Corolla 4.10 and 4.30:1 ratios

a H150 will last about 5 minutes longer than the H145 he keeps blowing up. I think that's the technical reason for the extra 5 being added to the 120Y's Jap diff

he has a sedan, so the shock mount is in the same location as the 120Y donor diff, but as Michael said, these plates simply go under the U-bolts so the mount location is no biggie anyway. But you should get those shock mount plates, because the U-bolts are wider apart in the 120Y setup so your 1200 ones won't fit.

the 120Y BW diff into a 1200 coupe is more work only if you count getting hold of a set of 120Y coupe bottom spring plates (that have the shock mount on them) as "more work". And the 1200 bump stop won't be wide enough to fit under both U bolts because they are farther apart. I just welded on a tag of flat bar to the bump stop to extend under the 2nd U bolt. But you could probably use the 120Y coupe bump stop instead (I say probably because I have not checked that out myself). I also shortened my bump stop rubber to compensate for the extra height of the 120Y axle tube. Again, this is not an issue here for the sedan.




now for actual stuff you need to worry about for the swap...

Michael is correct about the larger hole under the spring mount on the 120Y diffs. This can be overcome in a couple of ways:
1) use the 120Y spring centre-bolt and rubber mounted insulators which then fit into the hole in the spring mounts. But I wouldn't recommend this since you obviously drive it hard, because it could increase the chance of axle tramp.
2) I used some appropriately sized washers under the spring centre-bolt to fit up into the larger hole in those mounts - if you wanted to get reall flash you could turn up a pair of cylindrical spacers to do the same job.

I don't think there are any other problems - I believe I used the 120Y U-bolts, but I'm not 100% sure on that now. Length is a concern with the 120Y having 2 extra leaves and the rubber insulators as well as larger axle tubes... Memory's a bit fuzzy on that I might have had an extra leaf or two in my setup back when I did the swap.

You'll also need the 120Y bottom spring plates that the U bolts go through because of the larger axle tube, and hence wider U-bolts. And remember the shock mount plates for the same reason.

That about covers it. The 1200 flexible brake hose connects up to the splitter on the 120Y diff's steel line. As I mentioned earlier, if you get the handbrake cable up to the adjuster, it simply screws onto the 1200. And the tailshaft of course - whih is also bigger and stronger than the 1200's.

If only getting stronger gearboxes for the A series was this easy!

So are you saying that on a 1200 sedan diff which has the shocks mounted above the leafspring - the Shock actually mounts on a removable plate which is sandwiched between the diff and the leafspring?
I always thought they were part of the leafspring mount which is welded to the diff.
I must admit I never attempted to try and remove them as they always stayed together if I undid the leafsprings.
If I they are removable, please disreguard my original post.

well worht the swap to the Borg Warner, just don't hit kerbs sideways and you'll be fine. bent axels are never fun!!!!