1994 wrx auto. Gearbox or diff?

[riiidaa]

Your advice needed.

Bought a donor 1994 wrx, automatic - did a test drive and mechanically all was well, although I had the window rolled down at that time, what a ******* twat... lol

As I was going to be going on the motorway having slung £50 of V-power in it, I rolled the window up.

Then I could hear a faint whine, it was constant on the way back from Milton Keynes, wasn't sure if it was the gearbox or maybe / hopefully just a diff...

Carried on driving, then when we got passed Heathrow it started reving high when i put my foot down - like 5k rpm but it wasn't actually getting any faster. Almost like it didnt see any reason to change up.

Tried moving it from D to 3, 2 etc and it let me select that without any fighting, but it didn't make it work properly again.

It got progressively worse and 40mph seemed bearable but decided to pull up on the hard shoulder, by this time I'd reached j10 so limped onto the A3, pulled up on the had shoulder again and my mate tried to look at it for me.

He said he could smell a transmission fluid / gearbox oil type of smell. Placed a call to Moley who informed me the gearbox dipstick was near the TMIC. It got checked and it seemed ok according to my mate.

Guess I need someone who knows their scoobies to take a proper look. Don't have a handbook for a 1994 wrx, automatic so unsure of the correct procedure for checking the levels properly.

Whilst I'd prefer it not to be a knackered gearbox and say be a diff I think it's probably the former?

[2-jaffacake-tone]

Check the oil level, any history from when the g-box oil was changed last? I would recomend on a change if no history, to check level start engine put In to N. (make sure car is on flat suface) and check level on dip stick. If oil level and condion are ok sounds like a torque converter fault, As for the wining noise from experice more likely to be gearbox than diff.

Tone

[riiidaa]

Thanks for the info - after turning it on - how much time should elapse before checking the level Tone?

[2-jaffacake-tone]

Can't remeber if there's 2 marks in the dip stick for when the oil is hot or cold, I would start engine, pop bonet, find some rag, then check

[rogos]

the procedure for checking the atf level is as follows:
1. car on level ground.
2. start the engine (leave running throughout).
3. apply footbrake (keep applied throughout).
4. select reverse once it engages select drive and let it engage do this all the way to 1st gear with footbrake applied.
5. after you have selected 1st select neutral and leave engine running.
6. check atf level.

the upper full marker is for hot fluid and the lower is for cold fluid, (do not check it with the engine off because the dip level will be wrong). if the atf level is below the lower full marker then there is a good chance that you have burnt out the front clutch set like i did with mine if it was whining it could have also chewed the shim in the centre diff transfer from lack of oil as mine also did, hopefully its just a case of old fluid and sticky solenoids in the box. try some fresh atf in the box and hope for the best because the impreza auto boxes are very rare and hard to get hold of as i have found out, they are different to other subaru auto boxes because the impreza one has a vtd (variable torque distribution) centre diff that is a 45/55 (permanent) split (45% drive to the front and 55% to the rear) and 50/50 on wot. i doubt the front diff would be a problem as it is a slip diff so it shouldnt "wind up", the auto boxes are supposedly meant to be able to withstand a maximum of 400 horses because they have stronger gearsets. hope this helps all the best. nearly forgot, get some fresh atf and give it a sniff then smell the atf on the dip if it smells burnt and is brown then it will definately be a nackered box.

[riiidaa]

Hi Rogos, was yours a wrx or uk car?

[rogos]

Originally Posted by riiidaa

Hi Rogos, was yours a wrx or uk car?

hi mate mine is a wrx.

[riiidaa]

Like you say, these boxes are rare. Did you ever explore the possibility of using a UK GL 2.0 auto gearbox when yours went bust?

I ask because my decent car is a GL, I've done lots to it and so I wanted to turbo it. So that's why I bought this '94 WRX as a donor. But it's a real shed, in worse condition than I expected having been given the once over by Surrey Subaru Specialists who I took (trailered) it too for the ATF change. The car has a list of faults longer than my arm including HG.

[rogos]

i was originally going to fit a legacy turbo box to mine until i managed to get the right box. i do know that subaru's 4eat boxes have remained roughly the same in design since the 80's (google subaru 4eat for more info). as for the exact differences between the two i dont know but i do know that the turbos gearbox ecu will have better shift maps than the gl one, if it will swap over of course?

[jonnyricer]

mate of mine s wrx auto went pop it cost 1100 quid in out and rebuild place in hastings that did it.