Cab Mounts

[GMCGoat]

I have some rot on my cab floor where the body mounts are. And the brace that is under the floor is also rotted.

I was considering cutting out the rot with a solid guage steel, then instead of fabricating the brace, I was going to use a longer body mount. In my head this would be a lot simpler and still structurally sound as it would be simply to a body lift that you might do on an off road vehicle.

In fact, I might even consider adding 2 extra cab mounts in the center of the floor, but welding in some frame brackets.

Anybody have any thoughts on this?

[GMCGoat]

I uploaded some picks of the cab mounts so you can see what I'm working with.

http://s1276.photobucket.com/user/Jo...20GMC%20pickup

[msaintg]

I think (IMHO) that brace is needed to make the floor ridged all the way through the mounting point. If you cut back the rotten bracing and just patch the hole, then the floor might flex more. My cab was older and only had the seat support for bracing (which was removed by the PO) so I got a lot of flex when I went to mount the rear corners of the cab. I would repair the floor with some box tubing.

[mknittle]

Mike is right, besides if you just patch it you will be doing it again later only there will be paint to redo. Patching anything will always come back later to bite you!!!!!!
do it right the first time and be done with it.

[roger55]

I would not do what you propose. I would restore it to the way it was originally.

This is what I would do.

1. I would start out by taking the cab off the frame.
2. Remove the inside and outside frame mount brackets. Repair the outer ones.
3. Remove the rear cab floor support. Inspect, repair or get a new one if it's rotted.
4. Purchase a floor pan and at least replace the portion of the floor that's rotted.
5. Reassemble. Add a few more plug welds for extra strength. Seal everything with epoxy primer.

My question is about other rust damage. What's the condition around the front cab mounts? Looking at what you have at the rear mounts I have a hard time thinking you don't have issues there too.

What about the steps cab corners and door hinge pocket area? Any rust there? If so, it would make sense to deal with all that at the same time.

I am going through all of these issues with my truck as we speak. I don't have near of bad of issues at the rear mounts as you but my front mount area was pretty bad. I'm just replacing the front sections of my floor.

http://67-72chevytrucks.com/vboard/s...d.php?t=582950

[GMCGoat]

I don't want to do a frame of restoration on this vehicle. At least not now. And if I did, I'd most likely have to get a replacement cab. This vehicle has had a previous restoration in 1990's but it was more of a patch job (body wise). The roof was repaired and it is higher on the passenger side. This is simply a daily driver and a vehicle I can improve my skills on.

The new plan for the cab mounts is to fabricate some new braces with steel. I guess I wanted you guys to play devil's advocate and you did a great job. I got lazy there for a minute.

So here are the measurements after levelling out the cab with equal spacing between frame and floor.
Front: the spacing between floor and frame mount is 3 1/8".
Rear: the spacing between floor and frame mount is 2 1/4"".

I purchased these a while back:
http://www.lmctruck.com/features/ca/CA9B6.htm

One issue I am noticing is that for the rear mount, there was a rectangle bushing that goes on top of frame mount, and there was a circular bushing that went underneath the frame mount. So 2 rubbers. This kit uses only the rectangle in the rear.

So I think I am going to look for new cab mount bushings on-line. I might still use the LMC kit, but if I do, I will use both the rectangular and the circular bushings on the rear and get a new set of bushings for the front.

PS. Added more photos if you want the latest:
http://s1276.photobucket.com/user/Jo...20GMC%20pickup

[GMCGoat]

Originally Posted by roger55

My question is about other rust damage. What's the condition around the front cab mounts? Looking at what you have at the rear mounts I have a hard time thinking you don't have issues there too.

What about the steps cab corners and door hinge pocket area? Any rust there? If so, it would make sense to deal with all that at the same time.

http://67-72chevytrucks.com/vboard/s...d.php?t=582950

The previous owner put some 1/8" diamond plate in front floor, the underseat area is good steel, and the rear under gast tank area is still solid. The cab mount areas were rotted because all the salt they put on the roads probably gets into body mount areas and rots it out. The passenger cab corner was replaced but the driver side could be replaced. I actually might do that. One thing I don't want is this truck off the road for very long.

[GMCGoat]

Just ordered some body mount bushings from Energy Suspension. These are for a 63-66 but will get the job done.

http://www.energysuspensionparts.com...?prod=3%2E4137

[GMCGoat]

So I'm just finishing up the cab mount repair.

I cut out all the rot and then welded in some new thick steel (16ga.) in addition to some steel channel for added bracing. The channel is where the gas tank sits. I then seam sealed everything, and then primed and painted the floor top and bottom. I also painted the rear cab wall to clean it up.

Last night I put in the bushings, torqued the bolts. I also used anti seize on the bolts.

All in all, it is just a repair job, but I'm happy with how it turned out.

I'm priming and painting the new gas tank and then it will be time to bolt it all back together and get back to driving it.

Thanks for all your help guys.

[_Ogre]

repaired or restored, your saving it to drive.
well done

we like pictures, posting from photobucket is easy
use the IMG tag to post
nice truck, looks mostly solid metal