1999gmc
Active Member
I read a thread online about frame beaming on the GMT800 trucks, so I looked into it a little more and there was a guy who did a write-up on putting the hydraulic body mounts(2 rear mounts only) from a 2011 on up in the GMT400 body style. Cost me $150 for the 2 rear mounts, insulators, and washers from the dealer. I can't believe the difference it made in how the truck rides. They claim it will only fit the ex cab and crew cab trucks. So if you have an ex cab or crew cab, it is definitely worth the money to do. I think it is anyway. Wife and kids all noticed a difference in how it rode also.