So I have a 91 Legacy wagon AWD, 2.2, 5spd 270k miles. Non Turbo, No ABS.

This car has drivin like a champ the whole time I have owned it. I was driving in first gear at about 3000 rpm on a bumpy dirt road. No prior warning or noise. I was going about 15 miles an hour and all a sudden the engine revved up as if I was down shifting from a high speed to first gear. I immediately pushed in on the clutch and at the same time the wheels locked up and the car came to a sliding stop.

This was all accompanied by a loud single knock when the wheels locked up.

It wasn't the pushing in on the clutch that locked everything up.

It didn't feel like I just put the ebrake on, it felt more like all four wheels locked up but I could be wrong and it might have just been the back.

At this point I am on a slight downgrade. I couldn't shift out of first gear. When I tried to drive it would just kill the engine. I finally just gunned it and it unlocked and started driving. It drove like there was no problem at all. I jacked it up and I looked at all moving parts and I see no issue. I drained the tranny and the rear diff and checked the plugs. No metal shavings just the normal amount of very fine metallic dust on the magnet. I put my finger inside both drain plug holes and i didn't feel any metal shavings. I have changed all the cv joints recently so it wouldn't be them locking up. I have also put in a new clutch (kit). Any ideas? Has anyone ever had a rock bounce up into the drive shaft and lock the wheels up? :-\ Anything helps. Thanks.

that's interesting.

 

did you replace everything with the clutch - throw out bearing and the two retaining clips that hold it in place?

Yep I sure did. I figured if it had something to do with the clutch then it wouldn't stay running with everything locked up and my foot on the clutch, correct?

It almost kinda sounds like the differential locked up. Those don't generally just unlock on their own though. This is an odd one for sure.

Where did you buy the axles?

Easy.

 

Check the linkage.

I was driving in first gear at about 3000 rpm on a bumpy dirt road. No prior warning or noise. I was going about 15 miles an hour and all a sudden the engine revved up as if I was down shifting from a high speed to first gear. I immediately pushed in on the clutch and at the same time the wheels locked up and the car came to a sliding stop.

 

If the car locks up with the clutch in you have 2 gears engaged at the same time. This will always lock up everything. the biggest clue is the mileage (worn linkage) and bumpy road.

I bought the axles at autozone until 2 weeks ago when I got one at O'reillys. Have not been impressed with autozones boots.

As far as the linkage goes are you talking about the shift linkage? Do you think that's the linkage inside or outside the tranny? thanks again for the help

Edited December 1, 201015 yr by gravitate

SHift linkage, hopefully outside the tranny and not a broken fork inside the tranny. I bet it is in 1st and third

Well I checked the linkage and everything looks good. I put new fluids in my trans and my diff and then drove it around. Not a single problem yet.

I misread a shop manual a long time ago when I was just getting into cars and was under the impression that the transmission and the diff shared the same fluids so I never changed my rear diff just my tranny. I have had this car for 150k miles and I'm sure the owner before didn't ever change it either. The old oil was thick as cold honey.

Still don't have a clue as to what happened so if anyone wants to chime in please feel free.

I was just getting into cars and was under the impression that the transmission and the diff shared the same fluids

you've actually got that part right. on a manual transmission the *front* diff and the transmission share the gear oil.

 

in an automatic trans the front diff and transmission have different fluids - gear oil up front (like an MT) but the trans has ATF obviously.

 

rear diff as you know is a complete separate unit from the trans.

OK im perplexed.

Yeah I guess at the time I didn't know there was a front diff. They God for subies being forgiving. I put a used motor in this thing when I bought it, and forgot to put oil in it. I started it up and backed it out of the garage, about a minute later I realized what I did and shut it off. Never had a problem with it.