2007 cobalt sssc with LSD..ok i bought my car lowered with 75000 miles... everything was worn out so i pull all new suspension and steering components on the car... coil springs struts/shocks(all new mounting hardware) sway bar bushings and endlinks.. cab bushings.. ball joints... inner steering rack.. outer tie rod ends.. new hubs.. multiple new and reman axles.. intermediate axle shaft and "carrier bearing" .. oem trans mounts.. and passenger side engine mount.. (i ordered driver side engine mount for manual trans 2.2 on accident and it wouldnt fit..FS by the way...) all bushings are moog and all the suspension components are oem FE5 from CED.. so for about a week it rode and handled like a dream... after a couple days i noticed everytime i hit decent sized bumps on I95 i would start to feel a shake in the front end.. it got worse and worse every trip to and from work.. the suspension felt "bound up".. bumps were getting really harsh.. so i jack front end up and found passenger side axle was causing the shake... new axle.. shake went away but suspension was still harsh... one week later.. axle shake again.. another new axle.. but this time i unbolted all engine and transmission mounts and basically reseated the engine and reinstalled them.. drive the car.. RIDES LIKE A DREAM AGAIN... the suspension feels like its actually working.. car feels like its brand new... for about a week... suspension starting to get harsh again.. axle shake is coming back.. and it gets worse and worse with every big bump i hit on the interstate (like the bump up onto a bridge then the bump back off the bridge..).. ive uninstalled the engine mounts twice and its temporarily fixed my problem.. could that one engine mount i didnt replace on the drivers side be causing my engine to move and cause the axle to start shaking? and bind up the suspension? its not torn and feels just as stiff as the wrong one i ordered.. i ordered the correct mount but im just not sure its going to fix the problem.. any insight on this? btw the trans mounts are the ones from the lnf cars.. and yes ive gotten an alignment

 

update on this... i wasnt torquing the transmission mounts in the right sequence... loosen bolts on upper engine mounts.. torque rear transmission mount to thru bolt to 75 ft lb... then front thru bolt to 75 ft lb... if you start at the front you will have problems

 

Correct... you need to allow all the mounts to settle and have them torqued to spec in the proper sequence.