Cab body cushion bushings

[Casper42]

I just replaced my cab mounting hardware on all four corners, including bolts, washers, crush sleeves and rubber "OEM" bushings (aka cushions).

After doing some research, I found that there were currently only two types: the "OEM rubber" kit, or the Urethane kit for a performance stiffer ride. Mine are OEM rubber kit from Classic Industries but look just like all the others being offered by LMC, Holly, etc. They certainly don't look like OEM, but this is now what we are being offered unless one get's lucky to find NOS bushings. My research found these kits with no issues from other customers. However, I had to be creative and use additional washers between the cab and the frame to achieve spot-on body line symmetry from the cab to the bed. The problem with the current product, when comparing the thicknesses of the bushings, the new ones are actually about 1/8 of an inch thinner than my squashed down 51 year old OEM cushions. Seems very odd the new would be thinner.

I should point out that Brothers/Holly has an old video (Youtube) of how to replace these, and the ones at the time look near spot-on to OEM and they also point out in the video that the rear bushings are thicker than the front: the new kit they are all the same thickness. If this is the case, why doesn't Brothers/Holly offer this older version? Incompetence?

Have others found problems such as I described?

And yes, I did report my concerns of all this to Classic Industries by way of customer review.

[Jason Banks]

Here's a link to a different style...

https://www.classicparts.com/1967-72...info/35%2D145/

I used this set on a truck and within a year the front cab mounts seemed to be compressing and I went back in and added a shim. I'm not totally convinced it was a product problem and not an installation problem. Did I over tighten the front? Did I not have enough shim under the core support and when I tightened it, pulling down on the front of the cab?

Either way, I just ordered a set for a different truck and opted for the other less original style.

[Casper42]

I did not see these, thanks. I suspect you might be right by you over-tightening. By looking at that OEM style, such as what came on our trucks and what Classic Parts offer, they sure seem as though one needs to pay attention to how tight you get this by putting more trust in the lock-nut, compared to wrenching it down. My style seems far less likely to over-tighten as they are less likely (IMO) to compress.

Originally Posted by Jason Banks

Here's a link to a different style...

https://www.classicparts.com/1967-72...info/35%2D145/

I used this set on a truck and within a year the front cab mounts seemed to be compressing and I went back in and added a shim. I'm not totally convinced it was a product problem and not an installation problem. Did I over tighten the front? Did I not have enough shim under the core support and when I tightened it, pulling down on the front of the cab?

Either way, I just ordered a set for a different truck and opted for the other less original style.

[MikeB]

I've had the same set of Prothane cab-to-frame bushings on my C10 since the mid 1990s. They still look like new, are not affected by ozone, and will never let the cab sag. And I doubt I'd notice a difference in ride quality using rubber bushings. After all, it's a truck, not a Cadillac.

I've also used Energy Suspension or Prothane bushings on the suspensions of all the other old cars and trucks I've owned, from a 55 Chevy sedan to an 82 C10.

[HO455]

Maybe contact Wes at Classic Heartbeat. The ones I got from him for my Burban looked to to be spot on OE reproductions.

http://67-72chevytrucks.com/vboard/s...d.php?t=808538

[Jason Banks]

HO455 I forgot, if you need anything rubber for the trucks Wes is who to get it from:

Link to mounts on his site: https://www.classicheartbeat.com/pro...ing-1967-1972/

He's closer to Casper42 anyway

[Getter-Done]

Is the ones from GMC Paul's okay?

That's the one's I purchased.

[Casper42]

UPDATE: despite the need to add washers to build up the thickness to get body lines correct, the test drive with the new bushings is very nice. There is now no noticeable "old car" body lean in roadway curves. It handles the roadway imperfections, like potholes, closer to a newer truck than a Cadillac.

[pjmoreland]

Here's a photo that compares one of my original bushings to one from GMCPauls. The last two photos are the GMCPauls bushings installed.

[Getter-Done]

Originally Posted by pjmoreland

Here's a photo that compares one of my original bushings to one from GMCPauls. The last two photos are the GMCPauls bushings installed.

Thanks for the pictures.

That looks about right.

There was not much left of mine to compare.

[MikeB]

Originally Posted by MikeB

I've had the same set of Prothane cab-to-frame bushings on my C10 since the mid 1990s. And I doubt I'd notice a difference in ride quality using rubber bushings.

Earlier I said I'd doubt I'd notice a difference. Have any of you ever done a direct comparison -- new rubber vs. poly? I've only done worn-out rubber vs. poly.

[Casper42]

within the past year, I've done a pretty large amount of research from various forums and parts supplier reviews. My take was the consensus was poly was not recommended for anyone wanting a comfortable drive. Several customers stated it was just to harsh and they replaced or wanted to replace with rubber.

Originally Posted by MikeB

Earlier I said I'd doubt I'd notice a difference. Have any of you ever done a direct comparison -- new rubber vs. poly? I've only done worn-out rubber vs. poly.

[Casper42]

Excellent! nice side/side and install pix. Hopefully those will last you a lifetime, or at least another 25-50 years. I suspect my non-flared cushions will last a bit longer, simply because of that non-flare.

Originally Posted by pjmoreland

Here's a photo that compares one of my original bushings to one from GMCPauls. The last two photos are the GMCPauls bushings installed.

[MikeB]

Originally Posted by Casper42

within the past year, I've done a pretty large amount of research from various forums and parts supplier reviews. My take was the consensus was poly was not recommended for anyone wanting a comfortable drive. Several customers stated it was just to harsh and they replaced or wanted to replace with rubber.

Interesting. When I installed the poly cushions in the 1990s, the only difference I remember is the doors closed easier! But, again, those were some really worn out rubber cushions. I had actually bought them from a Chevy dealer, but they lasted only a few years. Maybe they had been sitting on the shelf, exposed to the atmosphere way too long. NOS with an emphasis on OLD.

[Ricks1971]

I bought a 71 4x4 and they had replaced the bushing with a Urethane kit and they took the truck off road and when I got the truck home the rear bushing on the cab actually crack rge can and I had to weld it up and put rubber bushing back in. A lot better ride