Suitable weight for Toad

D

david l greenberg

New member
Apr 13, 1998
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Generally I feel the GMC is limited in GVWR so the lighter the toad the
better.The issue of stoppability can be resolved with a brake system, any
number of varieties are available. I use a vacuum system fom P&E. There
is a more important issue, in my opinion and that is stress on the drive
train.

Several years ago at my first Sunshine Sttesmen rallyI met an owner who
was towing a Bronco. I asked him if he had any trouble with the GMC as a
result. He told me he thought the Bronco only weighed 2,800 LBS! We
checked the data plate and it was something like 3,800!

A year later the transmission went and the next year the engine went. He
continued to tow it until the rebuilt engine went. The moral: Tow
lightly!

I would not tow anything over 2,800 and anything over 3,000 rquires (in
some states and Canadian provinces) a brake system and break-a-way
system. Personally I think the GMC has all it can handle pulling and
stopping the coach, but having a car along adds considerably to enjoying
the destination!

And that is what I think, as Arch puts it!

David Lee Greenberg
GMC Motorhome Registry
200 MacFarlane Dr PH4N
Delray Beach, FL 33483-6829
561/243-0402
 
Dave,

There is no reason for the engine to go just because of towing. We have
used several tow vehicles over the years. The first was an Elcamino with a
454. No problems, but not many towing miles either. The first real towing
vehicle was a Dodge Van with a 318 Chrysler engine in it. It had over
150,000 miles on it (probably about 90,000 towing) when we took it out as
preventative maintenance. The motor still ran fine and actually used less
oil than the rebuilt 360 we replaced it with. The next vehicle was a Class
C motorhome which came with the Chrysler 360. We put quite a few miles on
it also without any engine trouble. The Elcamino towed an open one car
trailer, but the others all towed an enclosed 19' one car trailer ~6500
pounds.

We are now on the GMC. The 455 had about 130,000 miles on it (probably
about 70,000-80,000 towing half with ~6500 pound trailer and half with
~10,000 pound trailer). We were having some trouble with it 2 race seasons
ago, so we decided to rebuild it. The motor had 2 burned valves, but the
bottom end was PERFECT. Because we changed to forged pistons, the motor
actually went back together with more piston to wall clearance than it had
when it got taken apart! All it really needed was new valves and a new
intake.

We have never had transmission trouble in any of the previous vehicles. In
the GMC, we have changed the trans about every 3 years (~40,000 miles) as
preventative maintenance. One time, the trans shop guy said it was pretty
bad (probably due to final drive failure), but it never gave any symptoms
on the road. We have had the venting problem (started when we put in
outside dipstick, fixed now with breather tube), and also may have
experienced some slippage recently, but have yet to have any trans failures.

We have had a final drive failure occur. We had been hearing a noise for a
long time that sounded to us like it could have been the trans chain
dragging on its case. It would usually go away so we didn't think much of
it. After several more trips, we smelled gear oil a couple of miles away
from home. One of the bearings in the final drive had eaten itself up and
the seals were now leaking as a result. The final drive made it home and
even backed up the GMC and trailer into the driveway. We put new bearings
in the final drive ourselves and put another 20,000 miles on it before
changing to the 3.42. Considering the mileage and towing we had put on our
GMC, we do not consider the final drive failure premature. It gave us a
big warning with the sounds it was making as well, but we just didn't know
what it was. We do now :)!

I agree with the recommendation to add brakes to whatever you tow. It is
really the only way to keep the stopping distance close to what it is when
not towing. All our trailers have always had brakes. Our current trailer
is a triple axle with brakes on each axle. We have 12 brakes with the
trailer and GMC, and have no trouble stopping. In fact, it may even stop a
little better with the trailer than without.

If the GMC braking system is working correctly, it should stop very well.
We recently found that our brake booster vacuum line was severely
restricting vacuum to the booster. Upon changing that (we already had the
asbestos shoes in the back, bigger front calipers with carbon metallic
pads, and bigger wheel cylinders on middle wheel brakes), our stopping has
been MUCH better. Changing the vacuum line made the biggest braking
improvement by far out of any of our changes.

Just our experiences. YMMV,
Zak

>number of varieties are available. I use a vacuum system fom P&E. There
>is a more important issue, in my opinion and that is stress on the drive
>train.
>
>Several years ago at my first Sunshine Sttesmen rallyI met an owner who
>was towing a Bronco. I asked him if he had any trouble with the GMC as a
>result. He told me he thought the Bronco only weighed 2,800 LBS! We
>checked the data plate and it was something like 3,800!
>
>A year later the transmission went and the next year the engine went. He
>continued to tow it until the rebuilt engine went. The moral: Tow
>lightly!
>
>I would not tow anything over 2,800 and anything over 3,000 rquires (in
>some states and Canadian provinces) a brake system and break-a-way
>system. Personally I think the GMC has all it can handle pulling and
>stopping the coach, but having a car along adds considerably to enjoying
>the destination!
>
>And that is what I think, as Arch puts it!
>
> David Lee Greenberg
>GMC Motorhome Registry
>200 MacFarlane Dr PH4N
>Delray Beach, FL 33483-6829
> 561/243-0402
>
 
Zak, I yield to your experience and knowledge. I usually go with logic
plus gut instinct and am not always right. Close sometimes but not always
right!

My coach has only recently been put to work as a tow vehicle altho it
already has over 300k miles on the second engine. The first was pulled at
265k miles.

I suppose he tranny will carry the burden of pulling the toad away from
the traffic light in proud fashion! Long Live The Engine!

Thanks for the clarification.

David Lee Greenberg
GMC Motorhome Registry
200 MacFarlane Dr PH4N
Delray Beach, FL 33483-6829
561/243-0402
 
Dave do I remember you saying that you have a Mondello engine?

>Zak, I yield to your experience and knowledge. I usually go with logic
>plus gut instinct and am not always right. Close sometimes but not always
>right!
>
>My coach has only recently been put to work as a tow vehicle altho it
>already has over 300k miles on the second engine. The first was pulled at
>265k miles.
>
>I suppose he tranny will carry the burden of pulling the toad away from
>the traffic light in proud fashion! Long Live The Engine!
>
>Thanks for the clarification.
>
> David Lee Greenberg
>GMC Motorhome Registry
>200 MacFarlane Dr PH4N
>Delray Beach, FL 33483-6829
> 561/243-0402
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
 
FYI...

I just got back from Southland Motorhome Center in Buford, GA. Left my GMC
for some needed PM. I asked Zeb Frady, Jr about pulling a load on my GMC
because I want to pull my 1966 Triumph TR4A inside an enclosed PACE trailer.
Basically, he said up to 3500 lbs is no problem and I could go to 4000 lbs
if needed. Beyond this level, Zeb said, count on replacing the drive train
in 12 to 20 thousand miles.

Keep in mind - I don't know nothin' about GMCs. Just repeating what I was
told.

To get back to NC, I rented a U-Haul Transported and brought the TR4A with
me (off of the ground). It pulled like a dream. Some slowness on hills but
that 455 did the job. It pulled at 70 as easily as 55.

TW

- --
Thomas P. Winslow
1977 GMC Coca-Cola TZE167V101893
1974/75 GMC Eleganza SE TZE064V101146
189 Hicks Creek Road, Troutman, NC 28166
h704-528-5868 * f704-528-5868 * p704-878-1157
E-Mail: winslow * tom_winslow
Web Page: http://www.iredell.com http://www.iredell.com/gmc4sale.html
 
Tom,

Which part of the drive train does Zeb say fails? I'm interested in what
he feels is the weak link. I'm guessing that the trans is probably
considered the weakest link but would like to hear what he has to say. We
rebuild our trans every once in a while as preventative maintenance and
have not had any trouble, but we would be interested in hearing what others
are having trouble with.

I have to wonder how many others have actually tried to tow more than 3500
pounds. I have a feeling that the number of GMC's in this sample is
probably a little small to draw any real conclusions about failure ranges.
One thought I'm having is that many GMC's are not well maintained. These
motorhomes may have broken down in the 12-20 thousand mile range anyway
even if they hadn't started to tow anything. How many miles did these GMCs
have before they started towing? Every part has an expected lifetime. I
don't think GM designed anything to go much more than 100,000 miles back
then. Therefore, almost every one of us is riding on "borrowed" time on
one part or another. Everything will fail eventually. Adding a trailer
may just be pushing an already failing part over the edge.

With correct maintenance and some preventative maintenance, there is no
reason that the GMC can't tow more. We have not had such severe problems
with our GMC towing 10,000 pounds. We do 14,000 miles a year towing the
trailer. It would get pretty expensive replacing the drive train every
year :).

Our GMC has NEVER stranded us anywhere. We carry some spares that have
saved us a couple of times. We are pretty good at improvising. We have
also been lucky a couple of times. One time we made it home and into the
driveway when we probably could not have made it much further.

The closest we have ever come to actually needing a tow is an ignition
module that failed on the junkyard computer controlled distributer we
installed for our new fuel injection. It is something we should have
expected from a junkyard part. We had not yet had the time to buy the
correct spares. The only spare we had was a non-computer controlled
module. We rigged it up and got it to work. This experience was a good
argument for doing things yourself. Had we not installed the fuel
injection system ourselves, we would not have had any idea how to get it to
work with the incorrect ignition module, or even diagnose the faulty module
in the first place. It is also a good argument for replacing everything
you can on junkyard parts :).

Zak

>FYI...
>
>I just got back from Southland Motorhome Center in Buford, GA. Left my GMC
>for some needed PM. I asked Zeb Frady, Jr about pulling a load on my GMC
>because I want to pull my 1966 Triumph TR4A inside an enclosed PACE trailer.
>Basically, he said up to 3500 lbs is no problem and I could go to 4000 lbs
>if needed. Beyond this level, Zeb said, count on replacing the drive train
>in 12 to 20 thousand miles.
>
>Keep in mind - I don't know nothin' about GMCs. Just repeating what I was
>told.
>
>To get back to NC, I rented a U-Haul Transported and brought the TR4A with
>me (off of the ground). It pulled like a dream. Some slowness on hills but
>that 455 did the job. It pulled at 70 as easily as 55.
>
>TW
>
>--
>Thomas P. Winslow
>1977 GMC Coca-Cola TZE167V101893
>1974/75 GMC Eleganza SE TZE064V101146
>189 Hicks Creek Road, Troutman, NC 28166
>h704-528-5868 * f704-528-5868 * p704-878-1157
>E-Mail: winslow * tom_winslow
>Web Page: http://www.iredell.com http://www.iredell.com/gmc4sale.html
>
>
>
 
Just picked up the Motorhome Dinghy towing special 1999 guide for $3.99 at
Walmart. It has data on all of the "suitable toads. How to tow them and
everything else you have always wanted to know but were afraid to ask.

Also has a very good article on smart charging by none other than Wes
Cauglan of Cinnabar.

>Tom
>
>Thank you very much! Zeb would seem like a good source of information.
>OK folks look at what we have Zak is doing 10,000 pounds and does
>rebuild once in a while. Zeb is saying as much as 4000 is no problem.
>Can we see another myth about to bite the dust? The drive train is built
>like a tank like somebody said in here one time on the bearing survey
>I did. BTW the wheel that Lanier lost was with 7000 miles on the right
>bearings from Gateway.
>
>This is all making me feel very good! I think that I may be able to pull
>my new Suzuki Chia Pet with no problems. I got several back door
>messages telling me about 1000 pounds. All the manual says is you
>should consider brakes at that point.
>
>OK Thats it please send me how much you tow all the time or most
>of the time. Its time for another survey! I promise not to divulge your
>identity or anything about you. I will just post your words. I love this!
>If you have a gauge for the tranny temperature tell us at what temp
>the tranny runs at when you tow your load hell tell us at what temp
>everything runs at if you can. Oh yeah and what is the outside temp
>too. If any of you old pros know of another # we should know feel free
>to chime in. Gosh do I love this.
>
>Take Care
>Arch
>
>
>
>>
>> I just got back from Southland Motorhome Center in Buford, GA. Left my GMC
>> for some needed PM. I asked Zeb Frady, Jr about pulling a load on my GMC
>> because I want to pull my 1966 Triumph TR4A inside an enclosed PACE
>trailer.
>> Basically, he said up to 3500 lbs is no problem and I could go to 4000 lbs
>> if needed. Beyond this level, Zeb said, count on replacing the drive train
>> in 12 to 20 thousand miles.
>>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
 
- -----Original Message-----
From: owner-gmcmotorhome
[mailto:owner-gmcmotorhome]On Behalf Of Zachary
Zehnacker
Sent: Saturday, December 12, 1998 8:30 PM
To: gmcmotorhome
Subject: RE: GMC: Suitable weight for Toad

Tom,

Which part of the drive train does Zeb say fails? I'm interested in what
he feels is the weak link. I'm guessing that the trans is probably
considered the weakest link but would like to hear what he has to say. We
rebuild our trans every once in a while as preventative maintenance and
have not had any trouble, but we would be interested in hearing what others
are having trouble with.

>

I have to wonder how many others have actually tried to tow more than 3500
pounds.

{:-)

>

TW

- --
Thomas P. Winslow
1977 GMC Coca-Cola TZE167V101893
1974/75 GMC Eleganza SE TZE064V101146
189 Hicks Creek Road, Troutman, NC 28166
h704-528-5868 * f704-528-5868 * p704-878-1157
E-Mail: winslow * tom_winslow
Web Page: http://www.iredell.com http://www.iredell.com/gmc4sale.html
 
Tom,

>time). I feel almost guilty to admit that several times I hit over 75
>mph.>>>

We feel the same way as we hit 80-85 (usually to build up a little speed
for a big hill coming up). We probably have gone even faster at some
points (especially when the speedo didn't work). You don't realize how
fast you are going until you look down at the speedo. When it isn't
working looking down doesn't help much :).

>>>

Our front wheel bearings have been fine. I think the trailer tongue weight
on the back of the GMC actually reduces the loads on the front end. This
may actually increase front bearing life. It doesn't help traction though :).

>>> {:-)

I would think you would have good luck with this setup. It would be
similar to our original Wells Cargo trailer with one race car. Ours is
only a 23', but our extra supplies in the trailer would probably make up
the difference. The Wells Cargo probably weighed a little more than your
PACE too. How long is your PACE? With our original set up, with the
cam,intake,etc. we were able to cruise up hills at any speed we wanted to.
We were actually considering putting in the 2.73 final drive to pick up
some mileage!

>oriented. I am looking forward to a long term relationship with Southland
>Motorhome Center. I am going to drive the Coca-Cola down to pick up the
>Eleganza SE. Since I am going to sell one or the other I want them both in
>tip-top shape.
>
>They let us connect to the power next to their shop. There are four outside
>outlets. When I go back to pick up the Eleganza they are going to leave it
>connected to the power for our late 1 AM arrival. >>>

It is always nice to hear good things about GMC parts suppliers. We
haven't had a need to deal with them yet ourselves, but have heard good
things from others.

Zak
 
On Sat, 12 Dec 1998 19:42:53 -0500 "Tom Winslow"

>FYI...
>
>I just got back from Southland Motorhome Center in Buford, GA. Left my
>GMC
>for some needed PM. I asked Zeb Frady, Jr about pulling a load on my
>GMC
>because I want to pull my 1966 Triumph TR4A inside an enclosed PACE
>trailer.
>Basically, he said up to 3500 lbs is no problem and I could go to 4000
>lbs
>if needed. Beyond this level, Zeb said, count on replacing the drive
>train
>in 12 to 20 thousand miles.
>
>Keep in mind - I don't know nothin' about GMCs. Just repeating what I
snip........

Zeb should know as he pulls a trailer load of parts to the rallys but
having said that I could tell you it is okay to pull 3-4000 pounds too
with your coach but I wouldn't do it with mine!

That's for dang sure.

Dave G.
 
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