Body Mounts. Energy Suspension or standard?

[Paul Y]

More questions means that I really am powering on with Woodys build!

I need to replace the body mounts as the originals, whilst intact, are quite soft and compresses.

Question is, go for the OEM replacements or Energy Suspension hyper flex all singing and dancing red ones?

Is there a noticeable difference in NVH using the 'harder' bushes over the standard rubber?

Is body alignment easier/harder with the 'harder bushes?

Not so worried about cost - the difference is negligible in reality - just don't want to regret either choice if you have advice to give.

Thanks,

P.

[SkinnyG]

I'm on the fence with these on my '61.

I -did- do ES poly cab mounts on my '77 C10, and it was a noticeable increase in NVH, which most of the time is subtly annoying to me, and I'm seriously considering going back to rubber.

I bought poly for the '61, but we're a long way from the road yet.

[vin63]

I'm not a fan of polyurethane body mounts. On all of the truck builds that I've been a part of, including my own, I've used rubber mounts. I need to replace the mounts for my 64 Riviera and just purchased rubber mounts, as well.

[AcampoDave]

I tried poly cab cushions. NVH was pretty bad. Even the change in my ashtray vibrated from my exhaust. Took 'em out and went back to rubber. The difference was noticeable. I did a bit of research and the gist of it was; use poly for rotational things like a swaybar, panhard bar and anywhere cushioning isn't a factor. But for a smoother ride stick with rubber on A-arms, and body mounts. I did use poly in my trailing arms since they fall into the more rotational than cushioning catagory which seems to work out fine. Black poly is graphite impregnated to help reduce squeaks. Red is for a standout look and is not.

[Paul Y]

Gentlemen,

Thank you for the feedback, I have on,y ever used rubber body mounts on my builds but Poly came up as an option when I was searching Rock Auto (funny enough couldn’t find rubber mounts) hence the original question.

Dave,

I am on the fence about using poly bushes in the trailing arms as have read that they cause the arms to bind as they don’t allow any ‘twist’. Any thoughts or feedback on this as a real world user rather than a hypothesis?

P.

[Paul Y]

Good to know Skinny - feel that if I am going to the expense and bother of dyna matting my cab that using hard business with the inherent NVH is a bit counter intuitive....

Mind you, as I am also planning to run boom tubes this all might be a bit of a moot point....

P.

[franken]

I just used aluminum mounts on the Camaro. I don't think it's a big issue.
That said, if one buys Asian rubber mounts, expect them to fail in short order if exposed to sunlight. Asian rubber is less good than the rubber on your car now.

[SkinnyG]

Poly doesn't want to move in two different directions. In a front control arm, the forward and rearward pivots are in line with each other, so poly works fine there.

In the trailing arms, the left and right arm pivots are NOT in line with each other, so they -will- introduce bind, but whether, at such a long length, and such a subtle angle difference, and such a limited amount of rotation, it is enough misalignment to cause a problem remains to be seen.

I did buy poly trailing arm bushings for me '61, fully knowing this. I'll try it.

I fabricated a new panhard with poly ends, and it was binding problem for sure - I switched to rod ends.

My '61 has full poly front suspension and full poly motor mounts too. It has not been driven yet, so I might hate it still.

My '77 C10 daily has full poly front and rear suspension, poly cab mounts, poly sway bar bits, and fully poly motor mounts. The truck also has 1-ton coils and Big 10 leafs. The cab mounts made the worst change to NVH.

[66x3]

Am I the only one who has experienced this? I went to replace front cab mounts on my 66 C 20 ( with rubber) and found the top of the frame mounts rusted pretty much through. The older gent who bought this truck in 73 said " It never spent a night outside" and the truck was zeibarted at some point. I'm thinking the nights sitting inside caused this? Long story short what started as a pretty simple job got a lot more complicated.

[66x3]

( From sitting on a damp cement floor)

[Paul Y]

Originally Posted by SkinnyG

Poly doesn't want to move in two different directions. In a front control arm, the forward and rearward pivots are in line with each other, so poly works fine there.

In the trailing arms, the left and right arm pivots are in line with each other, so they -will- introduce bind, but whether, at such a long length, and such a subtle angle difference, and such a limited amount of rotation, it is enough misalignment to cause a problem remains to be seen.

I did buy poly trailing arm bushings for me '61, fully knowing this. I'll try it.

I fabricated a new panhard with poly ends, and it was binding problem for sure - I switched to rod ends.

My '61 has full poly front suspension and full poly motor mounts too. It has not been driven yet, so I might hate it still.

My '77 C10 daily has full poly front and rear suspension, poly cab mounts, poly sway bar bits, and fully poly motor mounts. The truck also has 1-ton coils and Big 10 leafs. The cab mounts made the worst change to NVH.

Skinny thanks for the analysis.

In my younger days I ran a fully rose jointed 911 street/track car and revelled in the lack of compliance and directness of the chassis. Now I think would want to shoot myself.....

Tried Rock Auto for the cab bushings but they only stock the Poly versions - any body got a recommendation for who to buy from?

P.

[Paul Y]

Originally Posted by 66x3

Am I the only one who has experienced this? I went to replace front cab mounts on my 66 C 20 ( with rubber) and found the top of the frame mounts rusted pretty much through. The older gent who bought this truck in 73 said " It never spent a night outside" and the truck was zeibarted at some point. I'm thinking the nights sitting inside caused this? Long story short what started as a pretty simple job got a lot more complicated.

That is weird.

Have you managed to repair the damage without resorting to taking the body off?

P.

[vin63]

Humidity is really pervasive. Having spent a lot of time working in Michigan, I can certainly understand the corrosion. I usually put a thin film of lithium grease on the mating surfaces of the bushings to help slow the moisture from making its way between the rubber bushing and mount.

Originally Posted by 66x3

Am I the only one who has experienced this? I went to replace front cab mounts on my 66 C 20 ( with rubber) and found the top of the frame mounts rusted pretty much through. The older gent who bought this truck in 73 said " It never spent a night outside" and the truck was zeibarted at some point. I'm thinking the nights sitting inside caused this? Long story short what started as a pretty simple job got a lot more complicated.

[66x3]

I'm in the process of welding new metal on the underside of the mounts, ground out the circular rusted areas and have a big washer recessed into that area and one of the square shims on top of that. The original mounts had one shim when disassembled so thinking it should sit about right. The rear (underbed) portion of the frame is a little crusty so pretty sure thats what caused the rusted mounts. The old truck is still in better shape than most michigan vehicles that age. Guess i'll see if my welds hold up !

[SkinnyG]

Originally Posted by Paul Y

Skinny thanks for the analysis.

No problem. Though I did edit my post to say the trailing arm pivots are NOT inline with each other (which is why they will bind).

I've been seriously considering changing my '77 back to rubber cab mounts. Nobody seems to have them in stock, if they list them at all.

I did have to weld metal into the cab frame mounts on the '61 as one (only one) had rotted through completely. My '77 was solid.

[Paul Y]

Originally Posted by SkinnyG

No problem. Though I did edit my post to say the trailing arm pivots are NOT inline with each other (which is why they will bind).

I've been seriously considering changing my '77 back to rubber cab mounts. Nobody seems to have them in stock, if they list them at all.

I did have to weld metal into the cab frame mounts on the '61 as one (only one) had rotted through completely. My '77 was solid.

Saw the edit.

Its a difficult one to decide which route to go as there is conflicting advice across the internet and, without being able to do a like for like/back to back comparison, I am not sure there is a right or wrong answer.

As most of us building trucks take several years from taking them off the road to re emerging, like a beautiful butterfly from a chrysalis, the previous 'feel' of the truck - pre mods- is a distant memory so this makes it even harder....

The decision on which route to go could actually have been made for me as there are no rubber mounts available anywhere... Good job my brother in law is a dentist....

P.

[AcampoDave]

These are what I have now. I kept the polys though, just in case... https://www.classicparts.com/1963-66...4aAtBMEALw_wcB

[Paul Y]

Thanks Dave,

They are actually in stock as well! Did you change the radiator support business at the same time?

P.

[cwcarpenter98]

Go ahead and get the radiator support mount stuff. Not all that expensive and it'll all fit in one box to save a little on shipping

[AcampoDave]

Originally Posted by Paul Y

Thanks Dave,

They are actually in stock as well! Did you change the radiator support business at the same time?

P.

No, but I probably should. Theyre likely shot

[M37-454]

Another vote for rubber cab mounts. I went with poly at first and the "tin can" resonance on longer drives bugged me enough to try a rubber set. I'm convinced it's quieter in the cab now and am sticking with rubber from here on out.

I can't speak to body alignment though, I didn't fuss with it since nothing is straight on my truck anyway. "Well used" is the nicest way to put it.

Lots of good info here! Body mounts are on the list. Rebuilding my front-end now, noticed that RockAuto only has the poly bushings for the front...I know from having poly bushings on the front of my Tacoma that they squeak (a lot) so looking for rubber there. Didn't consider the extra harshness of the body mounts but I will now.