Hello all,

Recently replaced the rear diff bushing thinking it would solve my "wobble" problem. As it turned out this is not the case (although it is sturdier compared to the blown silicone bushing). I couldn't find anywhere on the internets somebody with a similar problem.

This mainly occurs when i go over a speed bump at about ~10mph. it feels as if the clutch engages and disengages 3-4 time thus rocking the car back and forth (not sideways). It sometimes happens when the RPMs are a little high and i take my foot of the gas pedal. It is not the suspension because if i go over the speedbump without pressing the gas pedal there is no wobble. can anything be loose in there, or it is slipping?

Not sure if the clutch was ever replaced. it does slip (mild smoke smell) when going about 4K rpm in 6th gear.

06 MT - 74K miles

 

4K RPM's in 6th gear is 110 MPH with stock rear end. Are you sure this is what you meant?

Your low speed concerns over speed bumps just sound like play in the transmission. Pretty much every manual trans has some play in the tranny.

 

Definitely not 110mph. What i know for sure is that at 70mph its at 2.5K and closer to 3K at 75mph. Always thought that was a little high. Since a 1.8L car has these RPMs.
Any way to fix this play? I would think it is a solid connection from the tranny to driveshaft and diff and there wouldnt be movement in that direction. I should attach a gopro under the car and look for any movement.

 

4000 RPM would be about 110 MPH as indicated on the speedo of a G35 6MT. Our engines spin 3K RPM @ 82 MPH. If your car is saying you're doing 4000 RPM's at any speed under 110 then it's because your clutch is slipping like crazy the whole time.

http://www.car-videos.net/tools/spee...B1=Recalculate

 

Ill have to check on the weekend where exactly i stand with respect to the 3K, doubt ill try the 4K if it is indeed 110mph

id like to figure out the wobble however. it is in sync with the engine noise as if it goes from high to low RPMS 3-4 times while it rocks back and forth

 

Make a video of the RPM bouncing thing that you speak of. That would probably really help people on here to give you more productive input.