I have an 08 cobalt ss with an ldk and f40 swap. I vibrations/shakes in 2nd gear only at really low rpms, goes away after like 2500k 3kish rpm and you cant feel it in any other gear or higher speeds. Any idea what it could be? I also have axles from the driveshaft shop and zzp motor and trans mounts as well as bc coilovers. Thanks.

 

Could be something wrong with the transmission if the vibration is only tied to one gear. Was the trans new or used? I would make sure all of your engine/trans mounts are tight and properly aligned.

 

I have the exact same issue. did you ever figure out what it was?

 

for me it was the cv axles from dss that came with the kit from zzp. I ordered one axle from ottp and installed the old factory one from the f35 on the other side and problem went away.