Imperial-Blue-RS

Hope this is the right section...I'm after a bit of advice if possible please. My father in law has a Classic shape RB5, which once warmed up has a slight limp/jump, on turning left or right which has been confirmed as the diff, the box itself is fine annoyingly.
I'm just wondering which recommended people I should be looking at to have this done? I know there's the option of going for a six speed transmission, but as I'm sure you're aware they seem to be quite rare from what I can see and therefore is reflected in the prices.
My only issue is, I gather the six speed gear boxes are stronger, plus given the extra gear sit nicer on a long journey, from what I've been told, but its still a fair amount of money to spend on a box that I have no idea of the condition of, until fitted if you see what I mean, plus any potential associated dramas should there be a problem!
So my gut feeling is maybe get what I have already rebuilt by a recommended specialist, (unless its sell a kidney money?!) that or maybe buy a reconditioned unit?
Given this is probably a common occurrence given the age of these now, what has anyone else done in this situation?
Am I correct in thinking that the RB5 is just a normal 5 speed WRX box?
Any help would be very much appreciated.
Cheers
Mark

NOSSY_89

Just to get it out of the way, how did you confirm it was the diff.

You're a bit of a distance away from me, but I have a 5 speed with matching diff coming out. Going 6 speed dccd due to power now.

1509joe

iTrader: (2)

Simple and not time consuming job to do even on axle stands. Get a known good diff and replace. Box doesn't need to come out.

Don Clark

No it's a UK Turbo 2000 box - different ratios and final drive to a JDM WRX

Imperial-Blue-RS

Two mechanic friends of mine took a look and oddly both have Subarus, it was checked all over and the Diff flushed out a few times just incase, after that I took it to a Subaru specialist here in sunny Essex and he's confirmed what they think. He's snowed under hence me trying to source something.

Bit of a mine field as to what is and Isn't a compatible swap, even just trying to get a like for like from what I've seen, the 6 speed boxes are too much of a stretch on finding a few on the Bay (Jesus wept!), plus the owner is 77 and hardly going big power, I just want to get it back on the road for him as he loves it.
There are a few Subaru diff's for sale on eBay, but again which I'd need is another layer of complication, I'm a Ford man myself, so am a little out of my depth when it comes to these as much as I love driving it.
I do have a pit in my garage so if its an easy swap I'd consider that, are there any how too's or vids to show whats what if I could get one?

Right OK, that is interesting, I naturally assumed that it was just a UK spec box, that complicates it further then as even if I found a 5 speed then it would probably be wrong, is that correct?
See what I mean about not knowing what route to go with this, altho I may well be over thinking it, I'm just surprised by the different versions and box ratios even in the same shape?
Is there a serial number on the gearbox I should be looking out for by any chance, just so I know what I'm meant to be buying?

Thanks for taking the time to reply guys, it's very much appreciated.

Don Clark

As there are three diffs ( front - in g/b; centre - in g/b and rear - external) which diff have they diagnosed as faulty??
"Flushing" the front or centre diff would require changing the gearbox oil, but as the centre diff is a viscous fluid type, it would be pointless in doing. Similarly the rear diff is a Viscous LSD type.

"Skipping" on low speed turns can be caused by different tyre wear between front and rear axles causing the centre diff to bind and release.

An interesting read although the images are unfortunately missing. (Forester and Impreza have "similar" boxes).
https://www.subaruforester.org/threa...ce-them.46979/


An RB5 was/is just a " UK special edition" of the standard 1999 model year (MY99) "Turbo 2000" UK car as listed in link below
RB5

Both the MY99 and the MY00 models were fitted with the TY754VN1AA 5MT gearbox, and yes if you were talking about a UK Newage WRX (MY01-05) previously then they all have the TY754 series boxes with the same ratios.
MY01/02(Bugeye) - TY754VN2AA
MY03 (Blobeye) - TY754VN4AA
MY04 - TY754VN5AA
MY05 - TY754VN6AA

Centre diff part numbers: originally 38913AA100; superceded by 38913AA101; superceded by 38913AA102.

Imperial-Blue-RS

TOP MAN!
You're very quickly becoming my newest hero, thank you for all the advise, I really do appreciate it, especially with it being such a mine field to somebody not in the know.