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Motor Mount Replacement

135K views 86 replies 55 participants last post by  steviemal22 
#1 ·
I have been tinkering with the idea of changing my own Motor Mounts. However, after reading several posts and checking out a few how-to's the process seems a little more involved than what I may like to get into.

However, while I was inspecting a few posts and inspecting the engine itself, I was wondering if anyone else has ever changed the mounts without taking off the Fan clutch and jacking the enigne up as far as it could go. My question is this. Since there is a top engine mount bracket that bolts to the engine, would it be possible to simply brace the engine, unbolt the top bracket from the engine. Remove the the old MM and replace it with the new one. Put the bracket back on the engine. Put the nut back on the top of the new MM.

Just asking.
 
#68 ·
Having the same issue...got the passenger side with a bit of effort, but cannot get the drivers side. The front axle tops out on the frame and I am about 1/4" from having the mount clear the bracket. Car is jacked up separately with no weight on the suspension. Ideas?.
 
#70 ·
front end jacked up needed ??

Is there any benefit to having the suspension unloaded? (front end jacked up off ground)
I have a 2004 Olds Bravada and the shaking on cold startups/idle is starting to get really bad! Its AWD so i only ordered the easier passenger side for the first attempt. I've got around 150k on the odo.

I'm wondering if its just as well to leave the car on the ground/weighted and drive up on blocks or something to get the clearance needed to put a 2x4 under the oil pan. Seems that would save alot of jacking to get the struts collapsed if whole front end was up off the air on jacks.


Thanks!
mark
 
#71 · (Edited)
You don't need blocks or to do anything on the suspension. Just slide under the car and use the jack. I guess it depends how big of a person you are for if you can get under it without raising it at all...

Just follow the advice and you have to jack up a lot. For me it was helpful that i had a spotter looking at the radiator etc to tell me when I had to stop.
 
#72 ·
:woohoo:Changed out the motor mounts this weekend, thanks for all of the previous post.
It was not too bad. Didn't remove anything at all to get the job done. On the driver side I grinded off the unthreaded part on the top stud. With a little bit of force I got it in place.
I replaced the passenger side first, after replacing this one I snugged the bottom bolt to keep the heat shield in place. If not the thing will slide around and when you think you’re done the shield is turned around.

Thanks again everyone.
:thx
Vehicle Auto part Automotive exterior Car Bumper
 
#73 ·
Motor mounts-

I've got a really big problem. Of course no one knows until its too late :( In February I had a shop do my annual fix up. This ticket was two motor mounts, weld the top bracket of passenger side mount, Rack and Pinion Seal, Back brakes/Rotors, Alignment. Anyhow, I noticed of the rip a little vibration in the seat- they said its just stiff new mounts, they will settle...over 1k miles now...The vibration is awful now, in traffic.. any thing under 1 rpm. Ridiculous! I cant post pictures... but I did take photos. They are two different style/ sizes both have stickers 3021. I know the aftermarket complaint... of course I knew nothing before hand. When I took to the shop they said well they are the same.. maybe passenger side was on shelf for a while and they just changed they style. The noticeable difference is one is flatter- the bases are different- one is smooth round base, the other is a notched round base. Would this be causing roaring vibration lasting about 5 seconds? Any insight before I go bananas on the shop? They have offered to switch out the passenger side...
 
#74 ·
I have had the bad vibration at idle lately (110k mi. on the Envoy).
I bought 2 AC Delco motor mounts and so far have replaced the passenger side only. The vibration is completely gone, it idles and drives nice and smooth now. Drivers side will also get replaced since they are the same age.

The old mount is about 1/4" shorter than the new mount so I wanted to see how the mount is made and what went bad. I cut into my old mount with a hack saw and found out that the mounts are liquid filled and look like a large ball joint inside. They are not just solid rubber mounts!

Here is a picture of my factory mount cut away:


Very interesting!!!

Another tip for Trailvoys with 4wd:
I unbolted the passenger side motor mount, then jacked up the motor until the axle touched the frame. The mount still needed another 3/4" before it would come out. I then found it easy to unbolt the bracket from the engine block, remove the 2 lower bolts and just loosen the top 2 bolts. This lets you lift up the bracket and easily swap the motor mount.
 
#75 ·
Motor Mounts Changed!

Thanks for all the help! The new motor mounts are installed and the truck runs like new! My wife actually said that I did a great job. Then she pointed out the greasy hand prints on the bumper. As someone stated in a post, I removed the ECM and drilled a hole in the bracket in order to reach the top bolt on the drivers side. I also removed the lower bracket with the motor mount, which required removed the front tire to reach to bolts. All in all, not a hard job thanks to all the suggestions. A little over 3 hour job including a trip to the hardware store for a 18mm deep socket. Thanks again!
 
#76 ·
Thanks for all the help! The new motor mounts are installed and the truck runs like new! My wife actually said that I did a great job. Then she pointed out the greasy hand prints on the bumper. As someone stated in a post, I removed the ECM and drilled a hole in the bracket in order to reach the top bolt on the drivers side. I also removed the lower bracket with the motor mount, which required removed the front tire to reach to bolts. All in all, not a hard job thanks to all the suggestions. A little over 3 hour job including a trip to the hardware store for a 18mm deep socket. Thanks again!
Just did mine as well and thought I was pretty tricky drilling that same hole under the ECM until I read your post. :) One thing I do recommend is having something decent to cut the new mounts down with. I will say without a doubt a Dremel tool using that skinny cutting disk is pretty much worthless and will make this job WAYYYYY more difficult than it needs to be. Anyway, this was the rough idling problem that I've been chasing for 6 months...should have tried this earlier. Runs like a dream for the moment!

Jere
 
#78 ·
I just replaced the mounts on an '04. I used many of the tips in this thread. I used a dremel to cut off the excess, non-threaded portion of the new mount bolt.

There still wasn't enough clearance to get the new ones in. I jacked up one side at a time with the other still attached.

What I ended up doing was to hook a ratchet strap to the upper bracket and the offside wheel. This allowed me to rotate the engine just enough to get the new one in.

Probably not the professional way, but it worked like a charm.
 
#79 ·
I know this is an older thread and I hate to re-open it..

But are you just taking the tire off and going in via the wheel well liner? I have seen others do it that way on other cars but wasnt sure if that was needed here. It looks a bit tight but looks like maybe that is not needed.

If tires dont come off. Are you putting it ramps or anything or just sliding undef it while down low to make it easier to jack up the engine?
 
#80 · (Edited)
FYI for anyone looking to do a motor mount replacement. I did a video while doing mine (2005 Envoy EUV - I6)

They way I did it was remove the shocks/struts and dropped the bracket. I did film everything as the first side went really slow but I learned a lot by the time I got to the drivers side.

Hopefully this video would be helpful to anyone looking to do the same job.. first side took a couple hours, got it down to around an hour on the side that I filmed so hopefully it will be helpful to someone.. - https://youtu.be/Qc9MZzTMMwU

 
#83 ·
I have to say thanks to all those who have contributed to this thread over the years

I just replaced both motor mounts in my 04 Envoy XUV. Just turned 100k miles and I had noticed a vibration on start up with the engine cold. I had considered the motor mounts and found this topic when I searched. The symptoms described here covered many of the same things I was experiencing.

I followed the instructions here, and really only deviated in getting to the driver's side top nut. I used and combination of both an 18 mm Gear Wrench and a pass thru or go thru socket. Didn't have to take the PCM off but I did loosen the 3 bolts holding the lower engine mount bracket to the frame (did this on both sides).

As others have noted, in comparing the old and new mounts (I did go with OEM parts) there was maybe 1/4 to 3/8 difference in height.....didn't seem like much, but what a difference. No more vibrations throughout the cabin on cold start and the engine seems more quiet while driving. Shifts also seem a bit smoother.

Great thread and thanks to all who contributed.
 
#84 ·
Just did both mounts in my 2008 Trailblazer I6 2WD. Took about 2 hours. Followed factory manual (MOL), removed sensor, unscrewed fan clutch from pump, removed the 4 nuts on the mounts. Used a tip from here about keeping one side captured but movable while jacking the other side. Heat shroud sucks ass trying to keep it over the keyway during reassembly.
 
#85 ·
Hey All,
I am in the middle of the motor mount job on a 2005 TB 4.2L 4x4. The 4x4 gizmos seriously restrict the drivers side motor mount. I have the passengers side in, and I am wondering if now that it is 3/4" higher on the passengers side with the new mount, if that is not what is stopping the drivers side from lifting high enough. I am also wondering if I should put the old one back in temporarily to lower that side and lift the drivers side?
Another thought is loosening/removing the engine motor mount bracket (The top one with 4 bolts to give myself the small extra clearance needed?
Thanks,
Tom
 
#87 ·
Great thread and glad I found it before replacing them in my 06 Envoy. Good thing for the wheel cutter to trim the bolts down getting them back in. Once it was all re-assembled, the start up was like new...no more shaking and no shaking putting in R with the brake on. OEM mounts at RockAuto were 186 for the pair including tax and ship so not too bad. Saved at least 500 doing it myself. Removing the top 2 bolts on the fan shroud gave me just enough clearance jacking the motor up. Thanks!
 
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