OP
There isn't any way anyone should pay more that about 4k for that and only if it's got good compression and stands a chance of running. "Ran when parked" always scares me.
My 1978 GMC motorhome
- Thread starter Mike_H
- Start date
OP
I know you are in the middle of OTHER projects but it was sort of funny that when I was ordering my parts for my rear axle Carl from Jantz Engineering and I were talking and somehow your type of motorhome came up. He said that he sells his load bolt to about 10-15 of the GMC motorhomes each year. By adding the load bolt it helps to stop blowing up your front differential.
http://www.jantz4x4.com//jantz.php?p=detail&pro=load_bolts
Might be worth giving him a call? He said that guys ship him the diff assembly and he installs the load bolt and machines the ring gear and then sends it back to ya. If I remember out conversation correctly.
http://www.jantz4x4.com//jantz.php?p=detail&pro=load_bolts
Might be worth giving him a call? He said that guys ship him the diff assembly and he installs the load bolt and machines the ring gear and then sends it back to ya. If I remember out conversation correctly.
OP
Thanks for the info! I will call him. I wonder if he has access to installing new ring and pinion too. Its a third member, like a ford 9" or a 'yota axle. The only place to currently get a replacement ring and pinion is to buy a fully set up third member from a company that I've been less than impressed with.
He just might be able to get you new R&P. I know he has a LOT of connections with the stuff that he does. The company he gets the Super 60 gears from I know he works close with them. And he's a great guy to chat with.
425-327-0804 is his cell number. Just tell him I sent ya.....
OP
Thought this was a nice article about the GMC MH, for those interested.
https://www.stresslesscamping.com/blog/2020/3/2/the-gmc-motorhome
https://www.stresslesscamping.com/blog/2020/3/2/the-gmc-motorhome
OP
Boy...I thought the jeep was expensive to repair, upgrade and maintain. I'm buying a new rear suspension for it next week. The current rear suspension has a single airbag, mounted between the two bogie wheels. The wheels have independent pivots, and the swing toward and away from each other. The airbag between them is the "spring" that forces them apart. So, if that airbag "explodes" or develops a rapid leak, you lose all ride height on that side and you're stuck on the side of the road. Used to be you could just carry a spare bag. They are unobtainium now. Which means, If I blow one of my bags on a trips...I'm kinda screwed. I'd have to find someone with a spare they're willing to sell me or convert to something else, on the road, where I'd most likely have to pay someone to do the work. This is the original configuration. Another interesting tidbit about the rear suspension. The shocks work opposite the way you'd think. The motion end is at the top by the bag. The bottom is fixed. That means as the suspension is compressed, the shock extends in length. Its weird...and, of course, takes special shocks. KYB makes em. Bilstein makes em too, but they DON'T make front shocks anymore, so yeah, shocks are from KYB.
People have tried different methods to replace the single bag, and nothing works well. About the best I've seen is the "quad bag" set-up, which replaces the center bag with two bags on each side of a central weldment. Each wheel will be supported independently and the bags are common Firestones that are available everywhere. There are detractors from this style too, but its the one I'm going with.
I still have a front end kit to install too...Once these parts are installed, I will have rebuilt everything in the drivetrain but the Lower end of the engine and the transmission, neither of which show ANY signs of needing a rebuild.
The jeep is gonna be mothballed for a while...But someone did share with me a listing from a guy in Texas that is selling frames for 1600 bucks, painted and checked on a jig. Maybe when the MH is rolling again, I'll take a trip south to pick one up. Tie the frame down on the roof, and drive it home!
People have tried different methods to replace the single bag, and nothing works well. About the best I've seen is the "quad bag" set-up, which replaces the center bag with two bags on each side of a central weldment. Each wheel will be supported independently and the bags are common Firestones that are available everywhere. There are detractors from this style too, but its the one I'm going with.
I still have a front end kit to install too...Once these parts are installed, I will have rebuilt everything in the drivetrain but the Lower end of the engine and the transmission, neither of which show ANY signs of needing a rebuild.
The jeep is gonna be mothballed for a while...But someone did share with me a listing from a guy in Texas that is selling frames for 1600 bucks, painted and checked on a jig. Maybe when the MH is rolling again, I'll take a trip south to pick one up. Tie the frame down on the roof, and drive it home!
Simple question, Mike, and being asked strictly out of curiosity: If you had known what you know now about these vessels, would you still have bought one? Inquiring minds want to know!
OP
Yup. This more pressing question .. Would I have bought this one?Simple question, Mike, and being asked strictly out of curiosity: If you had known what you know now about these vessels, would you still have bought one? Inquiring minds want to know!
We knew going in that it was an old car, essentially, and it would need restoration. But, there isn't anything else like it on the road. Still the best design, IMHO, out there. The combination of living space vs size can't be beat. If I had children, my answer would probably change. If I had to replace it, I think I'd go with a 5th wheel toy hauler, something like @toximus is getting into.
OP
Dunno if you saw it... You replied while I was editing. I added some more color to the why, if your curious.
Just saw it, and yeah, it sounds like you pretty much knew what you were getting into, at least to some to degree. And I absolutely agree with there not being anything else like 'em on the road. They are unique, unto themselves, in many ways. So cool. So very, very cool!
OP
Tons and .... 29's?
Last summer I noticed a clicking in tight turns. Classic symptom of failing CV joints. So, I rebuilt one of them, and noticed they were still clicking... And that the upper control arm bushings were shot, the shocks were garbage and I wasn't sure what condition the wheel bearings were in.
Since this motorhome is FWD and its based off the first production FWD vehicle out there (Olds Toronado) the bearing set-up is a bit different than they make today. Its a Real bugger to change these bearings, requiring special tools and procedures to get the preload right. Plus, the parts of today aren't the same as they used to be. There are minor differences in new parts vs the old ones that can cause assembly problems. Finally, if the bearings give out, it will take the hub and knuckle with it. The service manual says the bearings need to be serviced every 20,000 miles! There are guys that will rebuild the hubs and knuckles. There are others that have installed grease zerks to help grease the bearings and say that they will run 100,000 miles that way.
Then there is a group out there looking for other solutions. One group figured out how to install the knuckles from a one ton Chevy pick-up. Its pretty interesting, you can read up on it here. It requires adding a bit of length to the lower control arms, which changes the Steering inclination angle. To counter that, the kit requires a 3" wheel spacer to get the scrub radius back into the right range. Ok, lets talk about the wheel spacer (because that is what EVERYONE calls out first). If you haven't noticed, my motorhome has very deep set wheels (high positive offset). They are essentially the same wheels that a dually pick-up runs up front, but mine are in all three positions. What most people don't know is that a dually pick-up will run a big spacer up front to keep the wheels in the right space. So...the wheel spacer is factory equipment (I just gotta remember to Lock-tite the damn lugs!)
After a lot of deliberation I decided to go to with the one ton kit. I'm a fan of unit bearings, which this kit provides. It also increases the diameter of the brake rotor and caliper (pics below). The ONLY non-factory part I need (that might need eventual replacement) is a longer axle, with standard CV ends for my MH. Everything else is pretty factory One Ton Pick-up. I looked into tracking down the junkyard parts myself and modifying my own control arms. I found someone supplying a kit though, with the welding all done. Not that I am afraid of the welding, but it saves me a TON of time trying to fixture the arms to make sure the balljoint goes in the right spot. So...I took delivery of a 500 lb crate from California
This was back in August! I didn't want to tear it apart during Camping season, then we started the kitchen remodel...So I'm finally able to work on it. Last weekend, I worked on getting the old parts off. My MH is in very good shape so it was actually pretty easy. Plus it has a bunch of oil leaks and torn CV boots flinging grease all over. No rust, LOL.
Here is the frame
I'll clean this up and spray a coat of paint on the rails. Probably pull the torsion bar and tie rods to clean them up and paint them too.
Here are the factory parts sitting next to the new One Ton stuff. The size difference is astonishing.
and all the new parts for one side of the coach
Now, all the removable parts are in my home shop (the coach is at my Folk's in storage). I have all new bushing and ball joints in the arms. I'll be cleaning them up and giving them a coat of KBS (like POR-15). The upper arms were small enough to fit in my blast cabinet, so that is done. The lower arms are actually really clean, so I'll prime the bare metal where the new balljoint mount was fabbed and scuff/paint the rest with some Chassis paint.
All the hardware odds and ends went into a bath of Evap-o-rust tonight. Some of the hardware is special and its still in good shape, so I'll get it all nice and clean then take it in for a Zinc Chromate treatment (like Metalcloak!) It's only like 35 bucks a batch, so its a lot cheaper than buying new. Its big stuff...1/2" and 5/8" bolts. And, again, they don't make the aftermarket stuff like the OE stuff. I wasn't sure what condition the hardware would be in, so I bought some new camber bolts. The stuff I got from Moog is garbage compared to what came OE.
Here is the hardware, in the tank. I still have one torsion bar "porkchop" to remove. It was the only thing corrosion seized in the whole front end. I spray it with Aero-Kroil and will go back later and drive the torsion bar out with a pneumatic hammer.
Last summer I noticed a clicking in tight turns. Classic symptom of failing CV joints. So, I rebuilt one of them, and noticed they were still clicking... And that the upper control arm bushings were shot, the shocks were garbage and I wasn't sure what condition the wheel bearings were in.
Since this motorhome is FWD and its based off the first production FWD vehicle out there (Olds Toronado) the bearing set-up is a bit different than they make today. Its a Real bugger to change these bearings, requiring special tools and procedures to get the preload right. Plus, the parts of today aren't the same as they used to be. There are minor differences in new parts vs the old ones that can cause assembly problems. Finally, if the bearings give out, it will take the hub and knuckle with it. The service manual says the bearings need to be serviced every 20,000 miles! There are guys that will rebuild the hubs and knuckles. There are others that have installed grease zerks to help grease the bearings and say that they will run 100,000 miles that way.
Then there is a group out there looking for other solutions. One group figured out how to install the knuckles from a one ton Chevy pick-up. Its pretty interesting, you can read up on it here. It requires adding a bit of length to the lower control arms, which changes the Steering inclination angle. To counter that, the kit requires a 3" wheel spacer to get the scrub radius back into the right range. Ok, lets talk about the wheel spacer (because that is what EVERYONE calls out first). If you haven't noticed, my motorhome has very deep set wheels (high positive offset). They are essentially the same wheels that a dually pick-up runs up front, but mine are in all three positions. What most people don't know is that a dually pick-up will run a big spacer up front to keep the wheels in the right space. So...the wheel spacer is factory equipment (I just gotta remember to Lock-tite the damn lugs!)
After a lot of deliberation I decided to go to with the one ton kit. I'm a fan of unit bearings, which this kit provides. It also increases the diameter of the brake rotor and caliper (pics below). The ONLY non-factory part I need (that might need eventual replacement) is a longer axle, with standard CV ends for my MH. Everything else is pretty factory One Ton Pick-up. I looked into tracking down the junkyard parts myself and modifying my own control arms. I found someone supplying a kit though, with the welding all done. Not that I am afraid of the welding, but it saves me a TON of time trying to fixture the arms to make sure the balljoint goes in the right spot. So...I took delivery of a 500 lb crate from California
This was back in August! I didn't want to tear it apart during Camping season, then we started the kitchen remodel...So I'm finally able to work on it. Last weekend, I worked on getting the old parts off. My MH is in very good shape so it was actually pretty easy. Plus it has a bunch of oil leaks and torn CV boots flinging grease all over. No rust, LOL.
Here is the frame
I'll clean this up and spray a coat of paint on the rails. Probably pull the torsion bar and tie rods to clean them up and paint them too.
Here are the factory parts sitting next to the new One Ton stuff. The size difference is astonishing.
and all the new parts for one side of the coach
Now, all the removable parts are in my home shop (the coach is at my Folk's in storage). I have all new bushing and ball joints in the arms. I'll be cleaning them up and giving them a coat of KBS (like POR-15). The upper arms were small enough to fit in my blast cabinet, so that is done. The lower arms are actually really clean, so I'll prime the bare metal where the new balljoint mount was fabbed and scuff/paint the rest with some Chassis paint.
All the hardware odds and ends went into a bath of Evap-o-rust tonight. Some of the hardware is special and its still in good shape, so I'll get it all nice and clean then take it in for a Zinc Chromate treatment (like Metalcloak!) It's only like 35 bucks a batch, so its a lot cheaper than buying new. Its big stuff...1/2" and 5/8" bolts. And, again, they don't make the aftermarket stuff like the OE stuff. I wasn't sure what condition the hardware would be in, so I bought some new camber bolts. The stuff I got from Moog is garbage compared to what came OE.
Here is the hardware, in the tank. I still have one torsion bar "porkchop" to remove. It was the only thing corrosion seized in the whole front end. I spray it with Aero-Kroil and will go back later and drive the torsion bar out with a pneumatic hammer.
OP
Just like anything else mechanical...you have to take care of the maintenance. Most people want to use it hard and put it away wet. Then they badmouth the product when it inevitably fails after 10 years of neglect. The deal with the GMC is that the newest is 44 years old at this point...so that is a LOT of previous owner neglect! It takes a small fortune to get them up to snuff. You basically need to go through EVERY system on the coach. Its like a classic car and an old house. If you have the right mindset though...man. There isn't anything else like them, at any price.
OP
Thanks. I can't wait until I get it to the point where I'm making improvements to the stuff you can see!