1994 850 Turbo slipping transmission under hard acceleration

JoeyG85Z · Post by **JoeyG85Z** » 20 Jul 2019, 13:26

A few days ago I was trying to replace the wheel bearings on my 850. Before I bought the car the previous owner had both front CV axles replaced at a Firestone Auto Care place. As I found out, the check who we installed things must have put the axle nuts on with an impact gun and without aligning threads. I tried to remove the right side nut with the car still on the ground using a breaker bar and a 4-foot cheater pipe. I couldn't get the nut to budge, but something did turn. There was a loud clicking noise, almost like the sound when you try and put a moving car into park. I gave up and put everything back together.

This morning I was driving to work and I floored it from a stop. When it shifted from 1st to 2nd gear, there was a big jolt and a loud noise similar to a slipping serpentine belt. It only lasts for half a second, but it's very pronounced.
Any idea what might have happened? I've got the ATSG for the transmission, but it doesn't have a power flow diagram that tells me what is physically engaged when it's in park.

Thanks
Joe

Post by **bmdubya1198** » 20 Jul 2019, 15:19

Have you checked the transmission fluid?

Also a pro tip... never use Firestone Complete Auto Care for ANYTHING unless you're just buying a battery there. Those guys have no idea what they're doing. I've had countless bad experiences there at multiple locations, whether it was me or a family member or friend.

JoeyG85Z · Post by **JoeyG85Z** » 20 Jul 2019, 16:08

bmdubya1198 wrote: ↑20 Jul 2019, 15:19 Have you checked the transmission fluid?

Also a pro tip... never use Firestone Complete Auto Care for ANYTHING unless you're just buying a battery there. Those guys have no idea what they're doing. I've had countless bad experiences there at multiple locations, whether it was me or a family member or friend.

The fluid level and appearance are good.

Generally, the only things I'll let a shop do on one of my cars are tires and alignment. The previous owner is the one who subjected my car to this torture. The store I work at sells a lot of parts to Firestone, so I know exactly why to stay away from them

Post by **bmdubya1198** » 20 Jul 2019, 19:25

Same, the only things I'm not equipped to do are tires and alignments. Otherwise, I love buying tools for anything else haha.

It may be a good idea to check those axles again and make sure they're installed properly. I recently had an issue with my S60 where an axle was broken (car didn't move at all though) and the parking pawl would grind whenever I put it in park. If you're driving it, that's not the problem, but it's worth a look to make sure the axles are fully inserted into the transmission.

That said, the squealing is a little odd, but I would start there just to rule it out.