Polyurethane bushings (energy sus): where to, and where not to

[EppNation]

Now that this technology has been out for some time and used by some (or most) of us, I think it'd be a great idea to share our experiences on where they may benefit, and where they should never go.

I'll start off with a POOR experience in MOTOR MOUNTS for my 6.5, not only was it a curve ball to my mechanic having to reuse old clam-shell housings, but resulted in negligible to negative results. Idle quality has become absolutely terrible, I'm almost embarrassed to have people in my truck if we are wading through traffic because of the onslaught of rattles when stopped while in Drive gear. Putting it in Park reduces the noise some, but no where near eliminates it. Ride quality while driving is good, but there's plenty of room for improvement.
I also replaced the TRANNY MOUNT at this time, so my culprit could be the combination of the two, but I have read lots of good results with tranny mount alone (when it was an isolated upgrade, unlike mine).

I caught myself looking at poly frame to body mount bushings, and thought: wait, these may not be best here. Basic logic tells me that soft, forgiving, run of the mill rubber will absorb and dampin my idle tremors far greater than stiffer, rigid poly replicas. Maybe if poly was OEM material at the time, it's benefits could have been implemented into the truck design, but that's not the case. I think it's more of a marketing scheme, cause the science is clear, in certain applications. It's certainly not universal. The demands of the sway bar bushings on a light duty pickup ≠ those of a tranny mount on a outlaw pro mod drag racer. They are the same as much as a sloppy joe is a rack of veal ribs in that their both FOOD.

Please share your experiences in swapping out factory bushings with ANY brand polyurethane bushings. Energy Suspension being the clear 'name brand' in the field.
Anyone use these in sway bars? Tie rod ends? Body to frame? strut/shock mounts? leaf springs?

 

[THEFERMANATOR]

If you look at energy suspension's website, they don't list the mounts for the 6.5's. I did them as well anyways, and HATED them. What a PAIN IN THE A$$, I know your mechanics pain about getting the clamshells apart, then manhandling them to get em back together, then spot welding them to hold them together. They are meant to go into the gasser clamshells, not the diesel ones. I took mine out, and put them in a friends gasser, and they went right in and worked great for him. The trans mount is fine. There is a different set of polt mounts that some use that are not as tight fitting that help with the idle rattle, but I thought they fit to loosely in the clam shells for my taste. I PROMPTLY went out and got a set of GM mounts to replace my poly mounts in mine. NEVER will I use poly engine mounts with a street driven diesel again.

 

[79jasper]

I've heard people's experiences with using them for body mounts. More negative than good.
I think I have them on my f350 in the track bar. In areas like that, should be fine.

Sent from my SAMSUNG-SM-G890A using Tapatalk

 

[WarWagon]

Use them for the A arms and front end bushings. Tightens the front end up a lot in corners and less steering input going straight. Love them and same "extra" labor. The first time I did the front end myself, the 2nd rig was subbed out to a shop...

Also the front ends feel loose when the rag joint on the steering shaft wears out. Ultimate replacement is here:
http://www.borgeson.com/xcart/home.php?cat=34

Used poly in the drive shaft center bearing. It got rid of the torque shudder when taking off with a trailer. (Doing a brake stand the drive shaft would jump up and down over 1". Yes, some suicidal trans shop owner stuck their head under the truck while doing this to watch it happen! ) The trade off for poly was extreme vibration at 75MPH+. Found later my splines are worn, but, went back to standard rubber center bearing and vibration is gone. As trailer tires aren't worth anything over 65 MPH this was a fine trade off. Was towing 100% of the time when we installed it. Got like 80K out of it before monsoon season drowned/ruined it along with the front hub bearings.
http://www.iedls.com/Center-Support-Bearings/Pickup-Trucks.asp

 

[SmithvilleD]

I've had the ES engine mount bushings in for a long time now & like them. Here's a link to a video I did years back showing the fast cranking speed of the Powermaster starter - a couple startups & idling in the video.

The video also shows how well controlled engine movement is - site from brake master cylinder to intake as it starts & stops. This helps allow a little tighter clearance btwn Duramax fan & shroud. While you can't really evaluate vibration level from a video, it's not that noticeably different than other 6.5's I've driven. There is a lot of variability in reports on these inserts - I don't question that some have too much vibration, but wonder if other factors cause it: variability in the clamshells, correct insert orientation in the clamshell, etc.? Any chance the idle ratter sounds metal on metal? Mine fit tight but easily clamped together.

I've got the rest of the total ES kit going in now: A-arms, sway bars, leaf eyes, trans mount. I've driven another GMT400 4x4 with ES bushings in the front & back suspension & just as WarWagon describes, they eliminate a bunch of play - truck feels notably less sloppy driving. You notice some additional harshness over the edge of road expansion joints etc., especially with stiff E-range tires.

3M makes a product called WindowWeld that can be used to incrementally (by how much you add to voids in engine mounts , etc.) stiffen up things like the rubber mount around a carrier bearing. I used it to dampen driveshaft tramp on a high 11 second AWD Eagle Talon years back.

Doing a body lift on top of the ES body mounts now. I don't do a lot of frame/body twisting manuevers, but still not certain if stiffer body mounts are good or bad in this case? We shall see how the body mounts work out.

 

[SmithvilleD]

After the work it takes to swap out the control arm bushings, went ahead and blasted & powder coated 'em silver vein - replicating the look of some aftermarket arms.

 

[Burning oil]

I to used ES motor mounts and trans mount. I like them a lot. Fit perfectly in the metal shells, no problem. No vibration.

 

[Paveltolz]

Nice work on the Control Arms. "Since you're in there" right?
I've used E.S. parst with mixed results. The Frame to Chassis, Transmission and Upper Control Arm bushings for the Rough Country set up went in very well. The Radiator Mounts were no where near correct. I just put in some replacement tie rod boots to replace the cracked Moog units and they went in fine.

 

[FellowTraveler]

I had got caught up in the ES 6.5 diesel thing and found the diesel mounts are the same a the 454 mounts and much thicker than other ES mounts for GM/CHEVY line.

 

[SmithvilleD]

Nice work on the Control Arms. "Since you're in there" right?
I've used E.S. parst with mixed results. The Frame to Chassis, Transmission and Upper Control Arm bushings for the Rough Country set up went in very well. The Radiator Mounts were no where near correct. I just put in some replacement tie rod boots to replace the cracked Moog units and they went in fine.

Yeah, I have '04 dual piston brakes (front & back) powder coated mirror black, and did the steering knuckles satin black. Anything left that's not coated just doesn't look right, plus once coated, they stay looking good longterm.

My ES kit had the correct rad core support to frame bushings - a bit shorter than the other cab mount bushings.

 

[GM Guy]

my main concern with the poly is age, I know our combines use polyurethane for the auger finger guides, and they will get brittle and crack out in 10 years or so. not that that is a short life, but IMO it isn't long enough.