Body mount questions

[NW_Ryker]

Hey all,
So the blazer is off at the body shop and their having some trouble lining the doors up. They rub back by the door jamb area. Right now, he's trying to line them up without the top on, and the body mounts are questionable. Should I have him put the top back on and line them up or should we replace the body mounts and send it back? How hard is it to do body mounts? Any help is greatly appreciated.

[my90k5]

I'm in the process of replacing my body mounts as well. I found that if before I bolt the top back on and I lift up on the rocker covers with a jack I can line up the doors then bolt the top down.

I'm going to attempt to replace my body mounts while the top is secure and the doors are aligned properly. My mounts are bad enough that if I take the top off the doors would bind.

Let me know your outcome......

[coyote72]

I can't begin to tell you how much sleep I lost over this same issue. I would first replace the mounts, and then you have to shim them to get the doors to work. When I did mine, the truck had sat and rotted for years and I had to weld in floor pans and the whole nine...I thought that was why I had so many issues. My doors were hitting the latch area as well as the wing window hitting the windshield post. Shimming the body was the only way to go. I have a GM build sheet that shows the procedure... I'll try and dig it up.

[NW_Ryker]

I will. My main problem is that it's getting painted so I don't want anything rubbing. Hoping someone will give me a crash course in replacing the mounts....

EDIT: That would be awesome coyote. There shouldn't be any rust left on the truck now as he's in the process of lining everything up and shooting paint. Would you recommend new body mounts and shimming it?

[coyote72]

I would do new mounts only because it will be much easier to work with new solid rubber. I got a bunch of huge washers (about 2.5" OD) and cut a slot in them to slide between the body and the mount and through the bolt. the washer looks sort of like a 'C'. After all the new mounts are in, I started with the mount right about where the door hinges from. Loosen the mount bolt, jack up the body, slide a few big washers in and let it back down and see where your at. It takes some time, but is the only way I found to make it right. On one mount I ended up with about 3/8" of washers to get it right.

[John H.]

You should change the body mounts before you have it painted. Put the top back on change the mounts and add shims where you need them. I bought mine from Classic Heartbeat in Olympia. Wes was very helpful and told me not to remove the top or do anything until I replaced the mounts. I added the factory shims back to each mount they were originally in. I listened to him and all is well! If the doors are hitting now, your tub is not sitting right. Putting them in the front closes the gap and removing any increases.

[NW_Ryker]

It wasn't rubbing before the top was pulled off. Do you remember how many shims you put in John?
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[John H.]

I only had 1-2 shims on the front two mounts and maybe 1 or none on the mount right behind the seats on the B pillar. Did you find any when you took the tub off? I replaced mine prior to taking the top off. Bad rubber on the mounts will cause the tub to flex without a top. You want to make sure you eliminate that when you have the top off and pull in a driveway with an angled curb or going off road. You will naturally get a little flex and this is the reason the factory put the metal plates in the door jambs to allow everything to rub without damage. You see these wedges on most convertible and even lager ones on Corvettes.

Depending on the condition, changing the mounts is not very hard if the bolts come undone

[NW_Ryker]

Never taken the tub off. Some of the mounts are pretty bad. How did you go about replacing them?
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[John H.]

You need to take out the bolt which is spot welded to the floor at each body mount location. Either grind the weld down or tap out the bolt if the weld is not to large. Obviously, if you have carpet, it has to come out. Once the bolt is out, jack the body up one mount at a time and replace the rubber pieces. Wes at Classic Heartbeat has the kits. I di not weld the heads back to the tub in case I want to remove. If you are able to get the bolts out, you do not need to jack the body very much to get the old ones out.

You really need to have the top completely secured to the tub too. This will prevent movement. Was there rust in the torsion boxes (rocker boxes)? It should not flex that much unless the rubber is completely shot or there is structural rust.

[Critter]

Originally Posted by John H.

You need to take out the bolt which is spot welded to the floor at each body mount location. Either grind the weld down or tap out the bolt if the weld is not to large. Obviously, if you have carpet, it has to come out.

This is by far the hardest physical part of the job. If I remember correctly there are 10 spot welded bolts in the tub plus the 2 in the radiator support. It was very time consuming for me because of the "ridges" in the bed area, it's hard to get to the bolt head without damaging the sheet metal. If you are working alone, honestly, plan for it to take a day.

Then after you change the bolts and put the new mounts in plan on another day of adjustment to get it right. This isn't physically hard, but it can be very frustrating trying to get it right. Maybe I am dumb and it doesn't take the rest of y'all this long, but its a pretty tedious job and it HAS to be done.

[NW_Ryker]

The Rocker boxes are solid. The tub is rust free. The only rust that was on the truck was upper windshield frame (being replaced), the front fenders and right behind the doors. The frame is rust free. Hopefully The rubber is pretty cracked and shot if I'm thinking of the right bushings. Thanks to everyone who's helped out so far.

[hotrodhomi]

I would put the top back on it to line everything up, then replace the mounts. The top will keep the body stiff while you are jacking up the body.

[NW_Ryker]

I ordered a set today. Hoping the body man can take care of it. A two day job turns into a month job pretty quick with my schedule.

[blazintowers]

what worked great for me was using a 4" grinder with a cut off wheel, you can maneuver it around pretty easy to grind just the spot welds off without touching the body. and don't forget your safety glasses or goggles!

[John H.]

If all the bolts come lose or break when removing, it was pretty easy. I was lucky. Here is what it will look like. You can see a shim up on one of the front mounts.

[my90k5]

Thanks John for the information nice pics. I'm in the same situation but wanted to wait for warmer weather so I could take care of the rust while I'm under there, lol.

P.S.

How did you torque your bolts? just tight by hand?

P.S.S.

ROFL!! I love the dust pan, just noticed it, lol

[Ridnhi]

I am in the same boat. I have a 71 at the body shop and have doors that rub the windshield frame. I just figured that I was stuck with the problem since the blazer has brand new poly mounts that were installed by PO so i figured nothing was wrong in that category. I do not remember seeing any shims. My guy is getting close to paint so I need to talk to him about this. So if I am rubbing at the top of the windshield frame, which body mount(s) need shims? Any help is greatly appreciated!!
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[John H.]

I just tightened them until they looked like the ones I pulled out. The bolts in the kit were too long so I could not get a socket on it.

As far as the alignment goes, you may want to ask you body man if you can tighten the front mount and behind the seats to pull the gap open. The poly mount might be thicker?

[blazintowers]

trial and error, you have to be patient and spend some time loosening, jacking, shimming, retightening, until you get her just right! you can get a good idea by jacking the body up at the exact location where your body mounts are located to see what the gap is going to do when shimmed at that location.

[coyote72]

Trial and error is the way it was for me. Here is the sheet I used to figure it out hope this helps!

[blazintowers]

nice addition Coyote72! very helpful....

[chuckmc8]

subbin in here

[NW_Ryker]

Thanks to all that helped. The amount of information you guys gave me is ridiculous. We dropped the body mounts off at the body shop today. We picked up a set without the bolts. Can you use the old bolts?

[SeventyOne]

I wouldn't. If it was like my truck, half of the bolts are nearly rusted in half. I would not want to trust them.