Diff related question

[Hash_ra23]

G'day Guys,

I've started on my task of changing my is200 to run a taller final drive as I'm running a V160 gearbox with the standard 3.91 ratio diff (too short for the box). I've reached a point where I need some assistance/advice.
So I've got the gears set from a RA65 celica which is the ratio I want (3.58).
From my research, I have found that the ring gear teeth are the same for both diffs and the ratio is set by the pinion gear.

First question:
1. Can I just swap pinion gears or should I swap the ring gear and pinion gear as a set.

Now I've been looking into the repair manual and it says I should replace the "pinion bearing spacer", which is the part circled:

From what I've read, this spacer sets how tight the pinion bearings sit in the housing and in turn sets the preload of the pinion gear and is a single use item. I've rung up toyota with the part number and they said it will have to be shipped from Japan.

2. Is this really a single use item, or should I just try and reuse it and check the preload?

I've read up on how to check the backlash so I should be ok with that part of it. I've also asked a diff shop to do it for me but they said it would be about $400 in labour

[e30-323ti]

I would be giving it to a diff shop and doing a complete R&P swap + new bearings.

The guy I use (4x4 nutter) doesn't use the crush tubes, he machines up custom fit solid tubes, he did tell me why but I've forgotten sorry.

Also, whilst the crown wheel may have the same tooth count, it must have a different offset from the pinion (which should be a bigger diameter on the 3.58 Vs 3.91), or it could be taken up on the centre's offset in the bearings but the IRS cases don't have much space...

Are these both F series diff's ? 7.5"

[allencr]

I'm with e30-323ti except for the bearings,

I would be giving it to a diff shop and doing a complete R&P swap + new bearings.

I'd be VERY surprised if the same ring gear accepted different pinions.
The crush tube spacer could be reused if it gets a big shim/washer added or is hammered on to lengthen it.

I've read up on how to check the backlash so I should be ok with that part of it. (

There are about 100 different ways to set it up wrong with a minor point, the backlash being correct!

[ToyTA22]

ring gear and pinion are lapped together from factory so the ring gear and pinion must run as a set. you could end up with some horrible noises if try interchanging gears.

As said earlier by allencr you fit spacer over piece of pipe in vice, pipe only in vice, then lightly hammer spacer as rotating each time you hit it. This has been done by mechanics for years when spacer not available.

It's not just backlash you need to set correct it's also tooth mesh position i.e pinion height which is adjusted by shim between inner pinion bearing and pinion. If you have a few shims available that's not to difficult to do.
You should also change all bearings and seals whilst at it, sames a lot of work later on.

[01-VEY]

I tried to change gears in a HQ sedan with a Salisbury diff. Peening the crush tube worked out OK but I had the meshing too deep. The gears ended up grinding themselves into oblivion and stuffed the LSD centre I paid a fortune for. That took about 400 km.
Definately a job for a Pro

[Hash_ra23]

Ok. Cheers guys, i'll get it done by pro. E30-323ti, they are both f series but you bring up a good point about the offset from the pinion. Im going to pull the diff out and compare them.

[mullett]

Go to amayama.com, order every seal in the box, new crush tube, nut, and all the bearings...then give it to a diff shop. Use toyodiy.com to get/confirm part numbers.

[mullett]

P.S. Is there anything stopping you swapping the whole housing? Or did they change the design?

[assassin10000]

I use the T-series TRD solid pinion spacer with an additional .7-1.0mm in shims in my F-series diff to get preload right.

Andrew

[mullett]

Is that to suit an RS200 diff in an old F series housing?

[Hash_ra23]

Mullet, the housing is totally different.
For reference I ended up getting a diff shop to swap the gears over for me. In the end it fitted up pretty well and only needed minor adjustment. This is using ra65 ring and pinion gears with the is200 LSD centre.