urethane or rubber?

[70rs/ss]

I am replacing the body mounts and immediately decided on urethane, that is untill I talked to Wes at Classic Chevy, he pointed out some things I had not thought about. He mentioned that the frames are made to flex and when wheeling they will flex a lot. Urethane does not flex, therefor the body will bare the brunt of the flex which will in time distort the body, break spot welds etc, etc. My question is, how many of you have swapped, what did you use and do you like them, and finally how is your Blazer used (wheeled, pavement, both) Thanks in advance for sharing your thoughts!!

[bouncytruck]

I have not changed body mounts but I have read that the urethane mounts may squeek and cause a bit more of a rough ride. On the plus side, they should last much longer and you can get cool colors, like read.

[Putter]

.....plus......no one ever looks at their date and says....
"Hold on while I grab a urethane!"
Geeeeeze.

[vtblazer]

Originally Posted by Putter

.....plus......no one ever looks at their date and says....
"Hold on while I grab a urethane!"
Geeeeeze.

[70rs/ss]

How about we keep to the subject? I am looking for information, not for my thread to taken in weird directions. If you used urethane great, tell me how they worked, if not how about you play somewhere else.

[bouncytruck]

Originally Posted by 70rs/ss

How about we keep to the subject? I am looking for information, not for my thread to taken in weird directions. If you used urethane great, tell me how they worked, if not how about you play somewhere else.

Wow. I was under the impression that this site was for fun. Sorry I replied to your post. I will make sure to keep all information 100% relevant to your specific situation from this point forward. I expect the same from you...

[Burt4x4]

I have had Energy Susp. urethane body mounts for over 10yrs now. I bought the black ones as I was told they are impregneted with polygraphite to prevent the "poly squeek" issue. The key to urethain is when you install the bushings do NOT over tighten the mounts. I used nylon lock nuts and tightend them carfully not to over crank on the nut. I have never found an issue with my body mounts. I even have a 3" body lift too boot.
My rig use to be a dayly driver but now it is towed to the trail.
So all in all I have had zero issue sence I installed the kit years ago...
If a urethain bushing is squeezed it cannot flex. So just make them tight but donot squeeze the mount and it will last a lifetime.
Burt

[70rs/ss]

Originally Posted by bouncytruck

Wow. I was under the impression that this site was for fun. Sorry I replied to your post. I will make sure to keep all information 100% relevant to your specific situation from this point forward. I expect the same from you...

Nah, not yours, but after yours it started to stray.... It is a site for fun as well as "INFO" which is why I posted this thread and just wanted this to stay on that path. BTW I usually keep my post to the point. Thanks!

[blazerboy72]

I used urethane in my 72 and will only use rubber from now on. They squeak very bad ride rough and did not fit good. I will be ordering rubber for my 71 soon.

[special-K]

I would say the body stress is not an issue.Burt4x4 wheels his pretty good from what I`ve seen in his pictures.Can`t be as bad as body lifts,solid.I`m sure brand new OEM-type have got to be sweet.I`m thinking of going that route next.

[bouncytruck]

Sorry, I was in a bad mood when I posted my last one. Sometimes ya gotta just kick back and have some fun. The serious info will make it. Actually, having more posts in a thread, serious or not, can generate more interest which will only get you better results in the end.

Besides, it was funny! "Hold on while I grab a urethane!"

Burt drive's his rig like it was intended. If he hasn't had a problem with flex, it probably isn't an issue.

[blazerparts]

I did poly on mine. Got the kit from Summit. Smeared them good with synthetic grease. For bolts I just got the proper length carrige bolts, nuts, and washers from Home Depot. If your rig hasn't had the mounts changed prepare to grind tack welds off. No strenous four wheeling for my blazer.

Never know, someday polyurethane condoms may be in.

[krue]

I don't see where someone cracking a joke is a hijacking a thread. It may be your thread but it's everyone's board. Take it easy and lighten up a little.

[FRENCHBLUE72]

Heres a few pics of my blazer with poly bushings that I bought at summit racing..... I don't really wheel the blazer much maybe 4 times in the 5 years I have owned it??? No squeaks and lets face it its a blazer with a 6'' lift its gonna ride rough...

[72CSTC5]

Amen Krue. Relax its Sunday. Last day of R&R before work all week. By the way, I bought the original rubber kit for my 2wd just because I have heard of body alignment problems with the urethane not being as forgiving. Putter, I thought it was funny!! LOL!!

[Yukon Jack]

I went with the rubber mounts for my K5 and part of the reason was to get all the bolts without having to source them on my own. Sadly my K5 hasn't moved since I bought it so I can't respond how I like them. I am using poly on my K20 with a body lift. I have never heard them squeak - course it is so loud, I can't hear much of anything other than the motor and the tires.

[qksilver]

In swapping out bushings make sure you use good bolts. Home depot bolts..............NO. Between stress fractures etc........I was working, recovering a wreck out of the woods, yes frames are suposed to flex. The frame flexed enough to break my carrage bolts, the only thing holding the cab to the
frame on the drive home were the front fenders. I can only imagine what would happen in any kind crash impact.

[Chevy Muscle]

Originally Posted by qksilver

Home depot bolts..............NO. .

I second that!!

I believe that Home Depot only sells grade-3 bolts.

[blazerparts]

Errrr, why not home depot bolts? In a connection such as a body mount with either rubber or polyurethane within the "grip" of the bolt, a hardened bolt is a waste of money. Add the factor that except for the radiator support and at the back by the tailgate, the head of the bolts are bearing on the sheet metal of the body which will fail long before a soft bolt.

While the frame may flex slightly, it won't flex enough to break a soft bolt at the body mount. If it flexed that much you'd be popping out windows, tweaking rocker boxes, etc. Frames are virtually rigid, the suspension is flexible.

Extreme conditions such as off road racing may require a harder bolt, but then the body would have to be modified with stiffeners at the bolted connection.


However if you feel better using a higher grade bolt, have at it. I'll be satisfied using my cheaper home depot bolts, which match the originals.


Oh, and chevy muscle, hope that "dumm" icon wasn't directed at me.

[13lazer]

i installed the red energy suspension kit with alot of grease, after some thought, i took them out. the blazer was 29 years old when i got it and most of the rubber was present. my biggest problem was the 3 broken bolts. i ordered the complete rubber kit from lmc. i had bad memories of my squeaky 71 camaro, my squeakier 67 el camino, and all the squeaky muscle cars in my high school parking lot. im just hoping to avoid all the noise. i just tightened all the o.e. mounts in my c5 and its very quiet. in my opinion, polyurethane is not a performance upgrade, and the polygraphite was not any quieter.

[Chevy Muscle]

Originally Posted by blazerparts

Errrr, why not home depot bolts? .

.....Durability of the part. You make an great point about it not being the weakest link in the mount, but I'm sure all of us have, or know someone who has had a broken body mount bolt.

Also, if these trucks are to last another 35 years, we will want to be able to remove the bolts again at some time. A harder bolt will be less likely to corrode over time.

Originally Posted by blazerparts

Oh, and chevy muscle, hope that "dumm" icon wasn't directed at me.

Of course not, my 'dumm' icon was directed at Home Depot. They ONLY sell grade-3 and don't offer a better quality bolt. I think they should offer grade-5 and grade-8 bolts as well. I know grade-3 is ok for most general construction of homes, but a lot of HD customers are building other things at times (like projects on their vehicles)

[donkey69]

Anybody reccommend a rubber and bolt kit from board vendors?