LS4 Performance - Car Shudders
03-03-2009, 09:04 PM
Recently installed the Billet Aluminum dog-bone and Ployurethane Bushings from 3800 Performance and have noticed the car sudders now when it downshifts from 2nd to 1st gear when coming to a stop and does it with and without applying the brakes . I expected to feel more vibration from the ployurethane bushings but didn't expect to feel the car shudder. Has anyone else experienced this phenomena with this mod, and any ideas what could cause this?
03-03-2009, 09:21 PM
Not sure if it's the same, but I noticed a shudder when I put the poly mount in my 06 Impala. I think it's being noticed when the DOD is transitioning between 4 cyl and 8 cyl. If I put the trans in D instead of OD, the DOD is canceled out and I don't feel the shudder.
03-03-2009, 10:48 PM
Yes, it is completely normal. It is the engine/trans shifting due to the lessening speed, and the vibration is transferred throughout the chassis. Mine was horrible from 25mph down to 10mph or so. It didn't help that the cold weather last winter made the ZZP Poly mount as hard as a rock. I passed the Poly mount over to someone down south and went back to the OEM mount twisted 90*. I did, however, buy a spare OEM mount in which I'll install the MSP bushing in the warmer weather. The cold really made the stiffer mount unbearable.