R160 and R180 - name the differences

tim_81coupe · Post by **tim_81coupe** » Tue Nov 27, 2007 8:03 pm

Hi,

My RX had a big problem yesterday and the result of it is I've had to fit my wagon's diff into it to get it going. I was told when i bought it that it had an R180 rear diff, although the backing plate (which has been off and on at some point) has an R160 part number on it. I know for a fact though that this is the wrong tag because the gearbox code indicates 4.11 final drive and the diff says 3.9 Now here's the pickle:

After swapping the diffs I've gone to bolt the tailshaft up and found that the diff flange on the tailshaft is 55X55 rather than 55x45 like on a normal R160. Is it possible that the other diff is in fact an R180 but with an R160 backing plate? Is it possible to swap the pinion flanges without affecting the pinion to crownwheel clearance? Forgive my ignorance on this issue as its been a while since I've stuffed with Fuji diffs...

In the meantime I am going to look at swapping the tailshaft with a single piece one I have but with a 4" tube diameter I am sure it won't clear the body and/or the gear linkages.

Any diff experts willing to give me a hint?

Outback bloke · Post by **Outback bloke** » Tue Nov 27, 2007 9:02 pm

No it isn't possible. The R180 is a lot bigger than the 160. You can see the difference plainly. What you have is an early diff compared to a late diff. They are known commonly as square and offsquare diffs.

An aside story to this: Funnily enough, when we were at one of the rounds of the arc a young fella blew his gearbox in his rs. They swapped the box for one that Subiworx supplied them along with the diff. We were watching them do this and we informed them that the later impreza diff wouldn't suit the tail shaft. Very unpolitley we were told where to go by the mechanic and that he had done this plenty of times before. We knew nothing apparently.

Should have seen their faces when we cracked up laughing at them an hour later when they were still trying to get it to work.

AndrewT · Post by **AndrewT** » Tue Nov 27, 2007 9:44 pm

Tim if it helps you can borrow my shortened tailshaft for abit - should be the right length. It's to suit an EJ gearbox in an L series, rear flange suits normal L series diff.
I won't be needing it till the wagon is ready to drive which is probably a month or more.

Suby Wan Kenobi · Post by **Suby Wan Kenobi** » Tue Nov 27, 2007 9:58 pm

The R180 is very much larger than the R160 and the difference is noticable even to a novice with them side by side. If you have only seen 160s the first time you see a 180 you will know straight away

tim_81coupe · Post by **tim_81coupe** » Wed Nov 28, 2007 8:25 am

Cheers guys, you've shed a lot of light on the issue.

I will give you a call about that tailshaft today Andrew. Thanks.

AlpineRaven · Post by **AlpineRaven** » Wed Nov 28, 2007 8:02 pm

Can someone show a picture of R160 & R180 diffs to see the diff?
Cheers
AP

Outback bloke · Post by **Outback bloke** » Wed Nov 28, 2007 8:34 pm

See if you can tell which is which.

D3V1L · Post by **D3V1L** » Wed Nov 28, 2007 9:47 pm

ive got an R180 diff in my rex.......definetly not the same looking as a L series one :P or a R160 for that matter

dave

Suby Wan Kenobi · Post by **Suby Wan Kenobi** » Wed Nov 28, 2007 9:51 pm

Nah most of the stuff lying around on the floor has only been there a month or so. The shed gets a clean up once a month and the crap gets taken away.

seagull · Post by **seagull** » Wed Nov 28, 2007 11:42 pm

Tim , I have checked every subaru diff front yoke after removel and they all measure the same deck height .So you can swap the front yoke over , if you need some help let me know ican give some help to swap the yoke over after work one day .
are you still at toyota welshpool ?

tim_81coupe · Post by **tim_81coupe** » Thu Nov 29, 2007 6:39 pm

Nope, I'm at Don Kyatt Spare Parts in Kewdale.

I ended up using Andrew's driveshaft and am going to have the spare L one in my garage shortened. I was reluctant to change the yokes for several reasons, one I don't have a decent air supply for air tools and two a new crush sleeve for an R160 is ex Japan (through Subaru anyway). Don't really want a noisy diff either.

Thanks for the offer though.

seagull · Post by **seagull** » Thu Nov 29, 2007 9:26 pm

Tim you will not get it off with a rattle gun , need a vice & a big braker bar

Re the crush tube : not needed if you dont need it if you have a set of fish scales on hand !

Phizinza · Post by **Phizinza** » Fri Nov 30, 2007 10:18 am

BYB-01 wrote:See if you can tell which is which.

Well what do you know, its about 20mm bigger... What a surprise.

All the Hitachi diffs are named accordingly to the size of the crown wheel.

Phizinza · Post by **Phizinza** » Sat Dec 01, 2007 9:15 am

Matatak wrote:so following on from that Phiz.

a R200 is 20mm bigger again?

jsut curious now.

Yes.

And also the R160 in the Subaru is a "longnose." R180's come in short and long nose versions, same with R200's. I'm pretty sure a longnose R180 has the same bolt placements and pinion shaft placement as the R160 so that would make it a pretty much direct bolt in except for the driveshafts.
ARB made a locker for the Navara which has a something spline shortnose R180. But it looks like they don't do them anymore. Still in their listings though.