Engine Mounts Failing

Jaredjeandron · December 26, 2016

I actually found out what happened, we forgot to put loctite on the bolts going through the mount into the engine block so all 4 bolts were missing. There's no way we forgot to put them in and torque them down but it's still rather embarrassing. For now the mount will have to remain as it has a lifetime warranty and has no signs of issues yet...and because money

Jaredjeandron · April 13, 2017

Update: I found out the motor mount bolts screwed into the motor were missing..not that they weren't torqued down enough, they were just gone..so I got four more from dealerships and they ran about $8 each but I lock-tite them and torqued them to about 100lbs. Now I have officially busted the mount..I think it may be because of the tires that I have on?? I put some 275/60R17 bf Goodrich tires on which are oversized by a lot and maybe they are putting stress on the mount? I don't go off-road much and when I do it's on an unfinished road so not play-time off road style. I was going 30 and had to floor it to get out of a sticky situation and now it seems the side rivets popped off from the metal clamp between the rubber. The rubber is holding up still. I have a plan to get street tires again just to get these off road ones off my damn truck. I think the bolts shook out because I road tripped to Austin from Fort Worth and anything over 65mph the tires wobble a little. Has anyone heard of tires causing this?? Sounds outlandish but with all the other mounts still in tact I'm out of ideas.

Heavy 5.7 · April 15, 2017

I put some 275/60R17 bf Goodrich tires on which are oversized by a lot and maybe they are putting stress on the mount? I don't go off-road much and when I do it's on an unfinished road so not play-time off road style. I was going 30 and had to floor it to get out of a sticky situation and now it seems the side rivets popped off from the metal clamp between the rubber. The rubber is holding up still. I have a plan to get street tires again just to get these off road ones off my damn truck. I think the bolts shook out because I road tripped to Austin from Fort Worth and anything over 65mph the tires wobble a little. Has anyone heard of tires causing this?? Sounds outlandish but with all the other mounts still in tact I'm out of ideas.

I'm not buying it. Are the threads stripped out of the engine block? Has this vehicle ever been in an accident? Is the cross member square?

Jaredjeandron · April 15, 2017

No wrecks, all the bolts are still in place and tight and it's hard to explain but it's a duralast driver side mount and there's metal brackets on each side with rubber and a metal clamp in the middle. The metal clamp was riveted to the metal bracket attached to the frame but now is separated. That's as far as I can tell without jacking the truck up, dismounting the engine and removing the mount. I'm assuming all I can get is a replacement part anyway so I guess I just have to go easy on the accelerator.

Xela Habob · July 24, 2018

I am on my second motor mount driver side I have a 2007 6.0 gm factory motor mounts both times have fail after speaking to my friend who drives otr pilot truck he has the 5.3 he has gone thru 12 sets of motor mount and 3 transmissions .i am on my second transmission.he has tried gm mounts ,summit racing mounts and has tried the off brand. He finally got a guy to replace the motor mount and welded 3 1/4 steel straps on 3 side of the mount.you can only feel a slight vibration at idle besides that it’s okay.this is very common problem with trucks,especially is you like to put your foot into it.

BLACK DEATH · August 18, 2018

My 2010 has a bad motor mount also.

When you take off above normal, you can gear it hit.

Mine has 195k miles on it, it towed a 2k trailer most of its life and it’s stock with no mods done to the truck.

joe v · October 15, 2019

09 gmc denali i just replace my forth driver side motor mount in august seems every 8 months they break i can always tell when i excelerate it pops it has the 6.2 and my wife drives it this time in august i replace both front mounts and the transmission mount and lasted only 2 months and yes its an ac delco is there any other frame mounts on this all wheel drive that maybe im not seeing

swathdiver · October 15, 2019

28 minutes ago, joe v said:

09 gmc denali i just replace my forth driver side motor mount in august seems every 8 months they break i can always tell when i excelerate it pops it has the 6.2 and my wife drives it this time in august i replace both front mounts and the transmission mount and lasted only 2 months and yes its an ac delco is there any other frame mounts on this all wheel drive that maybe im not seeing

Stop power-braking at the drag strip! Seems to me that you guys need the Hummer solid mounts, 25847739.