Pothole = Car shakes when in 4th gear?

jakethesnake · Post by **jakethesnake** » 22 Jan 2019, 00:00

Hey,

I had my gf pick me up from the airport last week and on the way she hit a nasty pothole on the freeway, going like 70mph. She said she heard a loud mechanical clunk and now my poor 96 850 turbo wagon (auto transmission) wobbles when it's in 4th gear, but only when i'm gassing it or when gear is winding down. When it's kept at a constant speed it's smooth as hell. Also gears 1-3 are running perfect, but once I hit 4th gear the entire car shakes.

No signs of a bent rim, so I'm thinking cv axle or transmission.

Any ideas?

Jake

Post by **RickHaleParker** » 22 Jan 2019, 00:14

Check your Strut mounts.

1. Open hood.
2. Stand on the side of car.
3. Grab underside of fender.
4. Fix your eyes on the top of the Struts.
5. Lift up on the car.

Are the Struts moving around in the Strut mount?

jakethesnake · Post by **jakethesnake** » 22 Jan 2019, 00:56

RickHaleParker wrote: ↑22 Jan 2019, 00:14 Check your Strut mounts.

1. Open hood.
2. Stand on the side of car.
3. Grab underside of fender.
4. Fix your eyes on the top of the Struts.
5. Lift up on the car.

Are the Struts moving around in the Strut mount?

The cap of the strut on the driver side rotated (seems loose) as I lifted. The pothole was hit on the passenger side, so I believe this is a separate problem.
It feels more like transmission, because the shaking only occurs in 4th gear.

Post by **jvl** » 23 Jan 2019, 08:02

I once hit a nasty ridge on the front right side at 70 kph, the car started vibrating as well. It also started drifting to the right, the alignment was totally off.
Not sure whether it was gear-related.

This is what I fixed to get rid of the vibration:

- new lower right engine mount (I think it was already bad and this was a final blow)
- had front left and right driveaxles replaced for used OEM at indy
- replaced both controlarms
- had new outer tie rods installed at indy + alginment

Hope this helps. I think many parts in this list were already old and this was just the final blow.
Check the lower right engine mount and control arm bushings for play first.

Good luck!

Joost

Post by **abscate** » 23 Jan 2019, 12:44

Could the 4th gear vibration be a consequence of the torque converter locking up and then transmitting vibration to the frame?

Post by **Clemens** » 25 Jan 2019, 01:16

if it were the torque converter, it would most probably not be felt when speeding up because then the converter won't lock up.