My 1978 GMC motorhome

Man...Some businesses just don't know how to communicate. I placed an order a week ago for a set of pins from a place on the West Coast. I called them, asked if they were in stock. He said, "Yes, they were. Do you want the reamer to ream the bushings after they are press to the arms? Its a rental, I charge 350 dollars for the deposit and give you 150 back when I get it back."

At least, that's what I understood. His phone connection was not great. I placed the order, thinking I'd have some parts by now. Haven't gotten an shipping email so I started to do a little more digging. I found another kit from a supplier in Florida (its actually pretty great that so many people make stuff for these coaches) and he was charging about 200 less than the first place, and 40 dollars less shipping. He was very responsive by email (the other guy has zero email skills or my emails always go to spam for him).

I called the first company and wanted to cancel my order. He said that's fine, as long as it hasn't shipped. I told him it still shows as processing on the site. He told me that they are really behind on paperwork. SMH. Anyway, he asks why it didn't ship and one of his employees told him they were working on getting the reamer back from someone...so he didn't ship, or communicate ANYTHING to me for over a week, after he told me everything was in stock. I did end up cancelling the order.

The pins should be out for a ride to Michigan tomorrow and I bought a fancy adjustable reamer with a pilot extension to add to my collection of tools I've bought for one time use! It was a used one on Ebay and its a name brand (Chadwick and Trefethan) that is still around, so if the blades are shit, I can get a replacement set pretty cheap (or have my guys make some). At least this particular headache saved me about 400 bucks and I get a new tool!

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I have to replace a cracked right side exhaust manifold on mine. My troubles pale in comparison to yours.
 
I've seen a couple of these GMC motorhomes eagerly awaiting to escape from their yard confinement. I think, that'd be a neat project and then I open this thread. I choose the vicarious route on this one. Thanks for taking one for the team.
 
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I've seen a couple of these GMC motorhomes eagerly awaiting to escape from their yard confinement. I think, that'd be a neat project and then I open this thread. I choose the vicarious route on this one. Thanks for taking one for the team.

Yeah...No problem! I'm kinda thinking about picking up a parts coach...so if there is something nearby that you know would go inexpensively...Lemme know!
 
Got one side of the rear suspension rebuilt today. Still needs to be installed, but I ran out of energy. First things first, I wanted to true up the cast steel box that the control arms mount to. Moisture had found it's way between that and the frame, so I had some rust to clean up. Ii had one of the guys at work help me with this project... We set it up on a Hurco VMX 64... It's a big bastard vertical mill, with 4 axis capability. We trued one side first, which is the way less important side, to help keep it secure when we machined the side that butts the frame

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Final result. I was not going for full cleanup, just enough to true the surfaces



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With all the rust and grease cleanup done, it was time for paint. I used the full KBS (or POR-15) system. I've found it works pretty well on stuff like this, where I can move the part around to keep it wet during their cleaner and acid etch phase

Here is the results after acid etch. Not great pictures, I know.

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And after paint. Decided not to top coat at this point. These parts are pretty well protected, plus the coach lives inside when we're not using it.
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Finally, today I did the assembly work. I drove my new bushing into the arms, then had to ream them to fit my new pins. Don't have a picture of that, but it was tedious and boring. I had to remove about 0.030 total (0.015 a side) from the bushings to make the pins fit. Once that was done, it was time to get the arms installed. That's was fun as well. The box is bored on the frame side to match the size of the pin and catch the head. The tire side is way big. They then installed a bushing with a flange on it, flange side towards the arm. They used two bronze thrust washers on each side on the arm to prevent the castings from running in one another. The reason for the moving bushing is so it can slide and take up manufacturing tolerance. Clever design... Pain in the butt to assemble. Taking a count... There are 7 moving pieces that all have to stay in alignment to put a single arm in the box. Oh, and each arm probably weighs 50 lbs. The guy of the bushing is very close... Like within 0.001" so everything needs to be lined up perfect. It was a GIANT pain in the ass. The first one probably took me two hours of cursing and repositioning, pulling it apart, putting seals in, again, because they fell off the thrust washers, etc.

I learned a couple tricks though, so the second arm only took me a half hour.

Here is the back side of the pin, assembled to the arm and ready to be torqued down.

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I'll get some more pictures tomorrow. Sprayed some rust reformer on the frame, so I'm letting it cure for 24 hours.

Can't wait to pull the other side apart and do it all over!
 
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My overly sensitive phone screen recorded a post reply command before I was ready... The previous post is complete now, lol

Hate it when that happens.

Impressive machine and great work. You are really attacking this project but in the end I'm sure it will be more than worth it.
 
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Hate it when that happens.

Impressive machine and great work. You are really attacking this project but in the end I'm sure it will be more than worth it.

My wife is really getting antsy, wanting to start on the interior. This should be the last of the "big" projects. I still should go through the fuel system, and the electrical is a mess... But it all still works.
 
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Spent some time pulling the passenger side apart today. I can't put the driver's side together until I get some shim stock to replace what was there (they used shims to adjust camber on the rear tires). Mine are pretty rotten. I am getting quotes on having a couple dozen made up out of 316 stainless. Each side has 8, 0.010" thick shims.

Here is the driver's side rear suspension, ready to go back on.

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I also couldn't help myself on the hubs. Had to clean em up and get some paint on them. They also got all new bearings/ races and seals. I used some machine gray, which is way more blue than I remembered, but I had the paint so I used it.

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Almost ready to set this thing back down on her wheels. I spent a bunch of time this week working on it. Had vacation from work, so I used it on the coach. Today I got both sides of the suspension mounted. Had an issue with one of the airbags, so I brought that back home with me. Rusty threads, FML.

Anyway... She's looking good.

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I also found that the calipers on the front axle were flipped side for side too. It's no wonder this thing stopped as fast as a boat.

I still need to bleed brakes, mount the manual air controls, fix the bag fittings on the pass side and have new parking brake cables made. With the calipers in the correct position the factory ones are not the proper length. Not sure what I'll do there.

We're camping next weekend... So it will be a big push this week to get it done!
 
I made it! Long push to get her done, but I got it. I still have some things to address. My wheel bearings are running a bit warmer than I like, my air bags have a leak, that I’ll have to chase down, my new front calipers rub slightly on the wheels, and my overflow bottle developed a leak. Had a nice little shake down trip this weekend. Drove about 40 miles for camping at a family reunion.

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