rear diff locking up after new transmission
 

Hi my names matt, no one really knows me yet but i work for dayle, at MotorSport Warehouse.

Just this passed sunday i put a used transmission in my 92. it runs great but when AWD is enabled the rear diff locks up about every 4 feet then i can put it in nuetral then back in drive and goes for another 4 feet and locks up again. When i put the FWD fuse in it drives great no locking. My cars not throwning any codes. I'm not to sure what to look for and was wondering if anyone could help me out

Thanks
Matt

Re: rear diff locking up after new transmission
 

So you put a used tranny out of (what car)???in your 92(insert model here)??
But it sounds like the diff ratio is incorrect :(

cam

Re: rear diff locking up after new transmission
 

its a 92 prl lsi all they put was a 92-95 used transmission... :(

Re: rear diff locking up after new transmission
 

From a SVX?

Re: rear diff locking up after new transmission
 

92-93 were LS-L. 94-97 were LSi. :D It does sound like that though, different FDR. If both trans were from svx's though you should not have that problem.

Re: rear diff locking up after new transmission
 

You might have to count the teeth in the front diff. to make sure it matches your rear diff.
Good luck

Re: rear diff locking up after new transmission
 

the guy i bought in from said it was a 92-95 svx awd tranny but also a couple things were different on it. like the speed senser and the shifter linkage doesn't line up prefectly but i'm guess that there different diff ratios but thank so guys i think i might just go to a five speed now lol:D

thanks
matt

Re: rear diff locking up after new transmission
 

At any rate, something wasn't done right, or the wrong parts were used, and your mechanic should be obligated to make it right.

Quick test you can put it in the air with the key on but the engine not running, put the gear selector in 1 and have someone floor the accelerator while you turn the front wheels, the rear wheels should turn at the same rate, if they do not, you have a ratio problem.

SVXes are 3.56:1, most other subies are 4.11:1 or 4.44:1 (legacy turbos are 3.90:1) so the difference will be pretty obvious.

Re: rear diff locking up after new transmission
 

Hi Matt.
What is the number of your replaced transmission?
There should be a label on the drivers side bell housing starting with TZ102....

Re: rear diff locking up after new transmission
 

Guys JDM's and Oz SVX's have a different diff ratio to your USA cars. When I changed my gearbox to 5 speed I had to get a rear diff crown wheel and pinion from the USA.

Re: rear diff locking up after new transmission
 

i'm the one that put the tranny in i don't let anyone work on my car but me. Not many people know about svx's in tucson.

And the numbers on the block are all riped off...

the cool thing is i got all my money back on the transmission and kept the trans

Re: rear diff locking up after new transmission
 

Well, you have a couple of options:

1) Figure out what your transmission came out of, and get a matching rear diff to swap in your car. Depending on what it came out of, you might be able to find a car in the junkyard with a limited slip rear end that you can get, otherwise you will either have to just swap in an open rear end, or change the gearing in your rear end (Which you will need to have a shop do, unless you have the proper tools & knowledge to set up a rear end). Some Outbacks and Foresters have LSD, but they are not marked on the case, you will have to rotate one rear wheel and see if the other one turns the same direction (LSD) or the opposite direction (open). Most Outbacks are 4.11:1, most Foresters are 4.44:1

2) Take the front differential and housing off your old transmission and swap it onto your new one. This is not very hard, but you will need some pretty big sockets to get the pinion shaft out. This could also be done by a Subaru dealer if you aren't comfortable taking your transmission apart. It's not super difficult, but it is easy to booger up the transfer clutches when reassembling the rear case. If you go this route, I would order some new transfer clutches and a torque converter shaft tube from Subaru.