1973-78 GMC motorhome as tow/support vehicle


PeteK

GT Owner
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Apr 18, 2014
2,283
Kalama, Free part of WA State
Forum meisters: Back in the 70’s GMC built a high-end motorhome that looked much like an Airstream trailer. It had rounded edges and an aero look, and was made of fiberglass and aluminum sheet. They built almost 13,000 of the things, and many of them are still around (estimates 8000-9000 per Wikipedia) because the bodies don’t rust out. GM had adapted the Toronado/Coupe Deville front wheel drive system to power the thing, and it had two non-powered rear axles with air ride. That allowed a very low floor (about 14"), and a low height overall, unlike the vast majority of RVs.

I’ve seen a fair number over the years, and in the early 1980’s a neighbor of mine had one. It seemed he spent a lot of time working on it, but that just might have been him (he was like some of us in that regard).

The question: I’ve considered buying an RV from time to time, and I’m getting the itch again. I like that the GMC Motorhomes basically don’t depreciate (unlike new RV’$!!!), and that the design style has held up over a long time. They often tow trailers. Does anyone have experience with these things? Advice?

I also have seen a few references to people who cut the back panels off a GMC and drove their cars up inside the back end (the body is 8' wide). Anyone know about that?

TIA, Pete K
 

Copenhagen GT

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Copenhagen, Denmark
I had one for a few years - 23 ft. Very cool RV. It is however important you buy one that is absolutely perfectly serviced and maintained. You can get most parts though a couple of specialized vendors. As with any vintage car - cost more to keep running than planned :)
 

Specracer

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Nov 28, 2005
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1st question, what are you towing? Open, enclosed, length? When kids were younger, and I was racing a lot, we had one. We did a lot of looking, and research. We have a 24' basic steel trailer. At the time, we did not like the class c options, basically a pick up truck, with a big heavy extra box. We had a 36 330 hp cat diesel pusher w air brakes. I don't remember the all the weights, and how we got there, but we did. It towed very well. We sold it a while ago. If I were doing it again, I would likely get a used toter. You can actually find them for less than a top of the line F350 dually. On the 70's GM RV, what's it's actual weight, and it's GVWR? How much can it safely tow?
 

PeteK

GT Owner
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Apr 18, 2014
2,283
Kalama, Free part of WA State
Light trailer with a car on it. The owner's manual says 2000 lbs towing, but from what I've read, people tow a lot more regularly. The gross vehicle weight is 12,500 lbs. I know it's not a real tow vehicle, so I'd only use it for that occasionally and for a few hundred miles at a time--like to get to Summit Point, or VIR. I might use it to go to Sturgis pulling the bike.

Copenhagen GT: Yes, I would look for one with good records, not high miles, and preferably with the upgrades that are now available. Gotta watch out for frame rust, or factor in $10,000 to put a galvanized frame under it. I think they are just cool designs, and they were designed as an RV from the ground up (literally), rather than adapted from a truck frame. I've spent about a dozen hours looking through the various web sites for vendors, owner's clubs, "for sale" and other info. I've looked at two, so I'm educating myself on their features, problems, and idiosyncrasies.
 

PL510*Jeff

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Nov 3, 2005
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Renton, Washington
See these all the time at vintage races. Talking with the owners, they seem to be pretty reliable and trouble free. Prices are fairly steady as it's a cult item.
 

Empty Pockets

ex-GT Owner
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Oct 18, 2006
1,361
Washington State
Something to ponder with regard to towing anything of any consequential size/weight/frontal area (or side 'windsail' area for that matter) with a FWD vehicle:

There are sound engineering and physics-based principles/reasons that explain why we've never seen Freightliner, Peterbilt, Mack, et al, build a FWD highway tractor...and why real pickup trucks (as opposed to the odd 'mini' here and there), whether used for towing or packing heavy loads, are all RWD (or AWD) as well...and, as regards trailering specifically, the main reason boils down to the optimum handling/braking/traction control that's provided by having the trailer 'tongue weight' located directly over or slightly aft of the drive wheels (5th wheel or standard hitch setup respectively).

My point: While one can occasionally fight city hall and win, the laws of physics/motion/inertia are probably best left unchallenged. ;-)

'Just my unsolicited $00.02.

'Going to my room now...
 
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PeteK

GT Owner
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Apr 18, 2014
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Kalama, Free part of WA State
Yup, all true. For best traction, it makes more sense to put the load on the driving wheels. But tractor-trailers and pickup trucks are towing things that weigh more than the towing vehicle. In this case it's the other way 'round. So, I'm willing to tow something that weighs a third as much as the rig, on occasion, using common sense and taking it easy. :wink

In the case of a motorcycle, I could probably find a way to load it inside the RV.
 

Specracer

GT Owner
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Nov 28, 2005
7,088
MA
My 2c, if it says 2000lbs, I would not even ponder towing more, any distance. The engine can likely pull more, but stopping, and load rating of tires etc etc etc.
 

Sinovac

GT Owner
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Jul 18, 2006
5,832
Largo, Florida
I would not scratch an itch for nostalgia with a vintage tow vehicle. The vintage vehicle belongs on the trailer.
 

AJB

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Jun 28, 2006
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Bloomfield Hills, Michigan
..Those are true words of wisdom ....'' the vintage vehicle or the new GT for that matter belong on or in the trailer.... not towing it....''
andy (ajb)