Car Shakes, Judders or Shudders in reverse or when downshifting

[RTERICK]

For anyone else experiencing this problem, I finally fixed it. The car would violently judder, shake or shudder in reverse and when downshifting but never in forward. First I changed out the transaxle mounts…did not fix the problem. Then I inspected the front motor mounts and was getting ready to change them (they looked OK) when I noticed one of the bellhousing-to-engine bolts was missing. This bolt was apparently missing when I bought the car a few years ago. On closer inspection the head of the bolt was broken off and the threaded end was still in place. Probably someone was replacing the clutch, broke the bolt head and then didn’t bother extracting the bolt, and just hoped for the best. From the engine side I tried to drill out the broken end using a right angle drill with no luck with titanium bits or cobalt drill bits…they hardly made a dent in the broken off bolt. Finally, based on some internet suggestions, I tried a carbide bit for concrete. Really did the trick and the bolt was extracted in a few seconds. In the process I messed up the female threads in the engine flange so I used a longer bolt with a washer and nut on the end.
No more judder or shudder in reverse or on downshifting.

[Ga 951]

Thanks for the tip. Glad you got it figured out.