LLY: Body Mounts

lts1ow

Needs moar PAH!
May 14, 2012
1,598
0
36
NJ
Truck is about to cross the 200k mark and want to start really digging through replacing all the isolators/mounts etc.

Body mounts are my starting point, thoughts on poly or the GMT900 stuff? Or keep it simple and get OEM replacement stuff.

'05 RCLB :thumb:
 

lts1ow

Needs moar PAH!
May 14, 2012
1,598
0
36
NJ
I worry poly will ride rough, least thats its usual complaint with my camaro
 

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
I would consider my ploy mounts to ride "sportier" not rougher.
Also go with the updated rear hydraulic body mounts. Great when they are paired up.
 

jpowel29

Member
Feb 1, 2008
780
0
16
Bentonville, Arkansas
I installed the red poly bushings on my CCSB. It definitely helped eliminate the spongy feel on braking/cornering. I did definitely notice more vibrations in the dash and interior. Similar to what you experience when you replace the soft, spongy engine mounts with a Merchant type engine mount. The poly stuff performs well but it does have it's trade-offs. I bought a set of the Dorman regular(non poly) body mounts and will try those along with the hydraulic rear mounts to compare with.
 

c20elephant

C20ELEPHANT
Apr 25, 2013
2,065
0
0
Phoenix, Arizona
I installed the red poly bushings on my CCSB. It definitely helped eliminate the spongy feel on braking/cornering. I did definitely notice more vibrations in the dash and interior. Similar to what you experience when you replace the soft, spongy engine mounts with a Merchant type engine mount. The poly stuff performs well but it does have it's trade-offs. I bought a set of the Dorman regular(non poly) body mounts and will try those along with the hydraulic rear mounts to compare with.

Still debating on the cab polyurethane mounts, the stock cab mounts right now look good. I have the Merchant engine mounts and Energy Suspension transmission polyurethane mounts, I would do it again no doubt....


http://www.duramaxdiesels.com/forum/showthread.php?t=71794
 
Last edited:

Kamilmk

Member
Aug 13, 2015
420
1
18
Seymour, CT
My truck is stock height. Not lowered or lifted, and after changing out the factory mounts to the poly ones, the ride is smooth. It isn't rough or bumpy at all. "Sportier" as stated above. I daily my truck, no issues. I can't talk for a truck that's been lifted or lowered, though, the ride on one may be different than what I'm experiencing.

Would recommend the prothane mounts for sure. I don't regret my decision.

Sent from my SAMSUNG-SM-G928A using Tapatalk
 

OregonDMAX

NOT IN OREGON, NO DURAMAX
Apr 28, 2013
3,964
8
38
36
Goodyear, AZ
The rear hydraulic body mounts are for a TSB update on GMT800 trucks for frame beaming. They definitely help alot, I put them on and love em.
But to be clear they are updated GMT800 mounts for a GMT800 truck not GMT900.
 

gmduramax

Shits broke
Jun 12, 2008
4,072
248
63
Nor cal

OregonDMAX

NOT IN OREGON, NO DURAMAX
Apr 28, 2013
3,964
8
38
36
Goodyear, AZ
The hydraulic body mounts for the TSB only fit 01-07 according to GM. Can't say for sure about any of the other ones.
 

chrisuns

Member
Sep 11, 2009
283
0
16
San Antonio, TX
Here's my posts from another thread about poly mounts:

I've had em for around a year or so and like them. But I also have every rubber bushing or mount replaced with poly. The only rubber that remains are the engine mounts and transmission mounts. Never squeaks at all - and mine are even the red ones without graphite.

More like a sports car like ride than anything, driving a stock truck feel terrible now because mine doesn't have the sloppiness and body roll that comes with softer rubber.

BE WARNED! They absolutely increase in cab noise and vibrations from the road, engine and lift pumps. 20-30% at least! and take into account I had sound deadening(like $500 in materials worth) prior to installing the full poly kit too.

Someone asked if I was glad if I did the change:

Oh yeah, I personally don't mind it until something starts vibrating with a passenger in the car (door card does it occasionally). That's the only bad part, the ride I love. I can't stand being in vehicles that people describe as if you're "floating on a cloud" - to me that's a design that sacrifices handling for comfort.

CCSB, LML 20s on factory SRA's, stock height and 8300-8500LBS with me in it.
 

chrisuns

Member
Sep 11, 2009
283
0
16
San Antonio, TX
Also, I changed the cab mounts first; so I drove around a few weeks with just those being poly, prior to changing everything else - they still increased road noise, but the biggest NVH effect came from changing the control arms, sway bar and leaf springs to poly.
 

lts1ow

Needs moar PAH!
May 14, 2012
1,598
0
36
NJ
Other than body mounts, I did find a full "set" of poly bushings, for like ~340.

For a 200k truck, should I just bite the bullet and attempt to do everything?