If you have half the fun that most of us have with our "ladies", then you will
indeed be  very happy .
 Oregon Coast
Also see:
  [FOR FREE] [Buyers Guide] [Where to buy a GMC] [I Love My GMC]
[Cost to Restore a GMC] [The First Start Up] [Newbie to Newbie]

If and when wanabees get serious about buying a GMC, the good and knowledgeable folks here on GMCnet may be able to help. And the more you can tell us about what you want, the more likely we'll help you find it. First, I suggest you study enough to be able to answer the following:

1. What length and floor plan(s) would be acceptable or unacceptable? Aside from looking at as many coaches as possible, a good source for researching this is ; Models & Floorplans)    Models, Floor Plans and Décor- FAQ)

where all the originally available floor plans can be found. Hopefully you can identify some configuration(s) you would not consider; like maybe a wet bath instead of dry, twin beds, or 23 ft. length.

2. Do you want a coach that has already had many upgrades, an "original", or something in between?

3. What features are "must have" or "must not have"?

4. Will you only consider a ready to drive unit, or would a fixer-upper be ok.

5. Where are you and how far will you travel to look at a prospective coach?

6. How much are you prepared to pay? That is, when you find your "perfect"
coach, what is the most you could pay?

Others may suggest different or additional criteria, but giving us a fairly detailed description of what you're looking for should result in many fewer inappropriate prospects. I think you'll find that most of us would be thrilled to help make you graduate to "newby" status.

This Section By Emery
What gas mileage should one expect with the 455? What about when towing a  second vehicle

 Gas mileage.  Depends a lot on the condition of the engine, tires, hilly  terrain vs. flat,  etc.  Probably 7 to 8 mpg is typical but some GMC netters  have reported up to 10.  If you pull a car it'll drop about 1/2 to 1 MPG.   This also depends on the weight of the Toad.  There have been a lot of  postings on this topic.  I think the general consensus is that it also  depends on the driver.  Two drivers of the same vehicle will probably get  different mileage due to the speed they drive, the acceleration rate, etc.

When in "auto" mode and the coach is parked should you expect the  compressor to run every once in a while or should?  How does one make sure it  is operating properly?

When in Auto mode the compressor may come on from time to time.  Why do  you have it in auto when parked.  Put it in Hold, use it to level the  motorhome and leave it in hold.  When you start the engine put it in AUTO.   If working properly there is a dash light that reminds to to put it in AUTO.   In the early models GM said to travel in Hold.  Then, because of air leaks  they said to travel in Hold.  Mine is a 77 and I have fixed all leaks and can  travel in AUTO and it rarely comes on.

 The fridge is AC/DC only.  Will it cool when traveling without the  generator running while cruising?  How long before the battery is drained.

The refrig that you have is most likely a Norcold.  This is a compressor type  refrig just like you have in your house.  The compressor has a 24v. motor.   There is an inverter/transformer to jump your 12v DC input to 24v AC and  there is a transformer that drops 110v AC down to 24v. AC.  It should work  fine on either power source but it will bring your battery down fairly  quickly if operated on 12v. when camping.  When going down the road it should  run just fine as the engine alternator is charging the battery.

Many of us have replaced this refrigerator with a 2 way or 3 way which is  either 110v AC and propane or 110vAC, 12v. DC and propane.  A tank of propane  will operate the refrig for many, many weeks.

The advantage of your Norcold with a compressor is that it will work even  when off level.  It has a freon system just like your roof air.  The propane  model works by providing heat 110v and 12v go to an electric heater in the  heat chamber.  This boils an ammonia solution.  The refrig must be relatively  level to work and can be damaged if operated off level.

Is there a list of common problems or things to check out before buying?

Things to check:  suggest that you check on Gene's website for a lot more information. The Buyers' Guide
Emery Stora

Do the normal "used vehicle" checks.  Leaks are always a pain to find.  Look for rotten plywood floors under the bathroom, under the water tanks, under the kitchen sink, inside the gen and propane areas. Be sure and look at the frame for rust, particularly where the rear wheels attach and particularly if your coach has "lived" in the road salt part of the country. Rotten floors and rotten frames are BIG jobs to fix.Gary

I think the frame could be a "show stopper" if it is rusted enough. It is a  major job  to repair the frame.  One coach I looked at just had a frame repaired and  the guy  had a $7,000 repair bill to show for it! Richard!

I'm doing that and have  some webpages dealing with replacing side rails, etc.


Zak has one,

and there is one by Lynwood Arthur">http://www.gmcclassi

Also Cinnabar in there latest newsletter had an extensive article on frame  replacement.

YES YES, look at the frame very good before buying----I know better now---I  might have taken it for free but to spend good money for one--it sucks!!!!! Scott

What is a good price range for this type of vehicle?

For an average good coach (everything runs, no rot, no rusted frame) expect to pay $16,000 to $19,000.  Expect to put $3000 with it when you get the coach to fix it up to your minimum standards.Gary

Valueing one of these coaches is tough - best to enlist the help of an experienced GMCer in your area.Patrick

The tires look new
Most people feel more comfortable with E load range rather than D range.  Alcoa wheels are preferred by most. Gary  Tires over 5 years old, will have to be replaced. You can read on this web page how to tell the age.

Outside is slightly faded, stripe is slightly damaged (wife doesn't care for  the color),

Expect to pay $4000 minimum for a decent paint job.  Many of us have paid nearly twice that amount.  The stripes are %$&@#@%% to remove and the adhesive remaining is even worse.Gary

 Generator is Onan 6K Watt.

Can be a source of great aggrivation if it is not running properly.Gary

 Also just out of curiosity if anyone has had one of these redone what was the  cost?


 Interior has no limits.  Just figure out the total square footage of the walls, ceiling, and floor; double it; then figure out how many $100 bills it will take to cover that area and you will be close.  But of course that can take years and years to "finish". Gary

For example are there any typical rust areas (frame especially) or  mechanical weak spots that require major repairs?

Since the body is FRP and aluminum, the frame is about the only place you need worry about rust.  Engine, transmission, final drive and front wheel bearings are other sources of expensive problems, but if you can handle restoring a rust-bucket like the old Mustangs, this is a piece of cake. :o)

Frame rust is the biggie.  Frame replacement is not for the faint of heart(or the light of checkbook).  Easy to spot tho' - just slide up under the coach and look at the rails.  Pay special attention where the rear suspension attaches to the frame rails as there's a subframe there and rust develops between it and the rails - evidence of this is a "flaring" of the frame rails at the subframe.  Take along a small screwdriver to poke suspect areas.Patrick

 I am not familiar with some of the terminolgy such as "wet bath".

The "wet bath" is simply a closet size room containing the toilet, vanity and shower.  To use the shower, you pull a shower curtain in front of the door and vanity.  The toilet gets wet with you, hence the name.  There were two "dry bath" versions - the side bath Royale, Avion and GMC rear-twin(can't remember the model name) add a small shower room next to the bath and the rear bath Royale has an almost RV-like bath that takes up the entire back of the coach.  All the "dry baths" eat up lots of precious floor space.Patrick

Check for maintenance records.  Trans and final drive oil should be changed annually.  Front wheel bearings should be serviced at 25,000 mile intervals.

It's good advice not to "fall in love" with the first GMC you find.  Since you're in Florida, you might have Jim Bounds or Alex Sirum take a look at 'er.Good luck,Patrick

Alcoa wheels
What's up with  those?  Are they a performance item?  An aesthetic item?  Any problem with non-Alcoas on these rigs?

The Alcoas are basically the only non-OEM wheels that will work on the GMC. The stock wheels are 16.5 inch while the Alcoas are 16 inch, which opens up your tire selection quite a bit.  If you want to keep the OEM wheels, you need to be sure that they are "Radial" wheels(they will be stamped as such either with the word "radial" or an "R" inside a circle).  If you run radial tires on the older bias-ply wheels, the wheels may "split" at the welds, which could get nasty.  The Alcoas are lighter and truer than OEM wheels, and they look better too.  So I guess the answer is "All of the above"<g>.Patrick

Regardless of the wheel that you use, you need to make certain that they are hub-centered wheels (the hub carries the weight instead of the lugs). The Alcoa wheel is  a within spec replacement wheel for the original steel wheels. Folks go to the Alcoa for many different reasons. Some of the reasons are:

1. they have non-radial wheels and want to use radial tires
2. they want to use 16" tires instead of 16.5" due to local availability
3. they need replacement wheels
4. they like the aesthetics
5. they prefer the lower weight

Any big deal bending and flaring your own oil lines, tranny lines, etc... I was thinking of buying a stainless  steel falring tool, stainless steel line, and replacing my tranny lines, oil  cooler  lines, etc...

   Making your own lines is certainly doable, but I understand stainless is VERY hard to work with.  Get normal plated (tin, zinc, copper, whatever) steel lines, and be SURE to double-flare them to minimize cracking of the flares.  When you think about it, you don't really need stainless.  The original steel lines lasted 25 years, yours will too.

Also plan on adding the vacuum booster pump (detailes in Eugene Fisher's  site).  Not quite sure where this ties into the engine vacuum.  Don't want to put it inline with the brake booster, but rather as
suggested  as a  supplemental engine vacuum boost.  Where does it tee in?  And does the  pressure  switch tee in seperately to monitor engine vacuum?

   Actually, the proper way IS to place it in line, just as GM did on the various cars it was used on.  That way, the engine sucks THROUGH the vacuum pump, and the pump's check valves add extra security when the key is off, helping the main check valve (at the booster) hold vacuum in the system.   If for some reason you feel an overwhelming need to tee the pump in on the side, you'll have to add a top-quality check valve between the tee point and the intake manifold.  Otherwise the pump will simply try to suck air and fuel vapors from the engine in the event of a stall, to the pump's detriment, and
providing NO vacuum to the booster.   The vacuum pump has its own switch (assuming it's inline).

 One more question, for peace of mind I may have the radiator re-done.  I  know  you have to raise the front to get the clearance to drop the radiator out,  but  does it come out in front or behind the shelf it sits on?

   Actually, the "shelf" is a U-shaped bracket which is unbolted and lowered down with the radiator.  It's heavy, and a PITA..  RTFM.  Take the radiator to a real TRUCK radiator shop for rodding out or recoring as necessary.  Be careful of the tanks and especially the oil cooler.  (It's no longer available.)  universal-fit spring-reinforced hoses.)   HTH.Rick Staples

    You have come to the right place for diverse and good opinions.

        I own a 78 Royale with a 403 with 135K miles on it and the drive train.
I went through all the thoughts you have expressed.  Here are my conclusions
which were aided by some really expert help from the net and attending a

I did the compression test and found the numbers to be as good as
a new engine.  I also measured the crank shaft end play and found it
to be like a new engine.  I noted that one post to the net suggested you run
a compression and leak down test and I heartily second the motion.
Personally, I would be very reluctant to get a rebuilt 455 with out specifying some
critical parameters including bearing types and crankshaft thrust surface finishing.
 you may be giving up an engine good for at least a 100K of reliability for an

So what must one do to get a little more out of a short stroke over bore engine like the 403 with out reducing it's high reliability?  Note the 455  actually has a stroke greater than its bore.

I got a lot of information to answer that question at my first GMCWS
rally at Ukiah last year.  Several guys mentioned a very noticeable
improvement in performance without significant changes in fuel economy by installing
headers and a clean  three inch exhaust system.  Lots of information is available
on this and the GMC in general at Gene's web site at
Additional performance gains can be obtained by changing the final drive ratio
from the present 3.07 to a   3.7 are available from Jim Kanomata
510-440-1101).  Again Gene's web site has information on gear ratios and
check the links at his site.

If you do the work yourself, the total cost will be under $2K.  If you do
as you are proposing based upon vendor recommendations it will be very big

 There is one instrument that I recommend highly and that is the addition
of a vacuum gage and possibly an engine tachometer.  Westberg Mfg
(707-938-2121) makes a neat dual function 2 1/16 TachVac that will fit
between and above the center line of two main instrument panel cut outs
with minor modifications.  Pictures may be found
at Gean's site.  A TachVac will aid you in operating your engine more

Another great gadget is a "Digi Panel" that monitors some critical engine
and transmission functions and creates an alarm when something is out of
wack (source: Digi-Devices 916-687-6905).

Also read and study all of Brent Covey's essays on the GM transmissions.
As he points out, driving technique has a lot to do with reliability of
the engine and drive train.  Namely, down shift manually to keep the engine
RPM in its best torque range when under heavy load (particularly the short
stroke 403).  This also keeps the torque convertor above the high slip
stall RPM range resulting in less heat generation and therefore less lost HP.

I intend to tow a small car and I am keeping my original 403 and transmission.
Happy motoring!    Regards,     Den 78 Royale


How bad will it be to try and start?

Take the buyers check list found on gene's page.

The battery will probably be down enough not to fire the engine, so take a battery charger and an ext cord.  Be patient.  While the battery is being charged up, Pull the plugs,one at a time, squirt a couple of squirts of Wynn's Supreme into the plug holes to lube the cylinders.  Let it sit while the battery is charging.

If the coach is where freezing weather could affect it, Then check the plumbing.  Look under the bathroom sink for the hot water tank, with a flashlight. you are checking for signs of freeze-up (cracks & bulges in the tank, water lines).  Turn on the water pump and open one of the faucets, see what happens (if
the water pump doesn't come on, it may only mean that the house battery may be low).  As you walk to the rear, the water tank is probably under the left (passenger side) couch.  Pull out the face and look around there.  See if there is any water in the tank.  The water pump is also there.

Pull the oil dip stick and check for indications of water in the oil, or a very high oil reading on the stick (again, water in the oil).  Very low (way over a quart) add a quart.  Up to a quart down, don't worry about it - the dip stick may not be properly calibrated.

When the battery is up, turn the engine over easy, don't worry about it firing.  If that works, then pump the gas pedal to prime the carb.  When the engine fires, don't race it, let it work easy for a while.  Oil can be changed later.

When the engine starts, you will hear a roar from the fan clutch and a noise from the air compressor.  Time how long the air compressor runs until it quits (the air bags should be up).  3 - 5 minutes, from empty seems to be average.  Set the valves to travel.  Then you can think about taking it for a ride.  If the compressor cycles, that's ok at first.  If it doesn't, that's even better.

Wayne Newland  F9300  75 Palm Beach  Columbia, Md

*New Oil Filter, check oil level, doesnt really need a change right off the

*Turn engine two complete turns by hand, either at harmonic balancer, or
take off gravel sheild at torque conveter and turn by ring gear teeth

*disconnect coil + lead and crank engine three times ten seconds, breaking
for 30 seconds between attempts

*connect fuel supply to fuel pump inlet with fresh hose, near front

*Re-Connect coil, and start her up, she'll go. When it catches, run the
engine at a fairly fast idle for ten seconds then turn it off to let the oil
drip down inside and lubricate everything, namely the cam etc.

*Check for fuel and oil leaks

*start it again and run it for a few minutes, but DO NOT LEAVE IT
UNATTENDED! Theres always a risk of a fire or leak occuring from dried out
seals or animal nests etc, so keep an eye on it.  Hope this helps, Brent Covey

Cost to Restore a GMC
Tom Warner

 I know that there are many of you that have either just bought a GMC motorhome or are contemplating buying one. When I was looking for a coach I wondered whether I should buy one with all of the work completed, paint, alcoas, E rated tires, new interior, upgrades etc,or one that was cheaper that I could repair and upgrade myself. But I always wondered how many of the repairs or upgrades were accomplished correctly so they could be relied on.  Big question when you consider a coach.

There are of course several things to consider when making this choice,paramount is your mechanical ability to do the work or to pay to have it done, whether you have the cash to lay out all at once for a completed coach, the condition of the fixer-upper etc.

I chose to buy a coach that was decent but which I knew needed repairs since it had been used very little in the previous years. I paid $11,000 for a 1976 Palm beach with original paint and an interior that had been refurbished but which we did not particularly like. It had 53,000 original miles on it, nice straight accident free body, nice looking Michelin D rated tires(two blew out shortly after buying it) and would not go over 30 miles an hour. It ran just terrible!

To date I have spent a little over $12,000 for parts only. I have done all of the labor. Here is a list of the parts I have installed to date to give you some idea of the scope of the work involved.

7 New Alcoa 16" rims and new Michelin XPS rib E rated tires
6 KYB gas shocks
new carbon metallic brakes front and back
new calipers
new brake hoses
new brake lines
new wheel cylinders 1 1/16" mid axel and 15/16" rear axel
repacked with mobil one and inspected rear bearings and new seals
new stainless steel air tank
new fresh water tank
new sensors
new floor from the bathroom rearward
new fresh water pump
new vacuum pump for brake assist
new Rostra cruise control (thanks to Dwayne simmons, a netter)
new stewart warner "wing gauges"....not installed yet
new dana air pump
new stainless steel one way valve and air filter for the air tank
New suburban 35000 btu furnace
new Norcold N671 double door refrigerator
new statpower 40 converter
new statpower TC40 remote control for the converter
new Ramco mirrors (thanks to Jerry Wheeler, a netter)
new steering shock absorber
new lower ball joints
new hubs
new knuckles
new front wheel bearings and seals
new tie rod ends
new steering links
new prothane sway bar bushings
new prothane end links
new steering knuckle boot
new air bags with aluminum cones
brass fittings for air bags with shutoffs
about 80% new brakes lines
new Rochester quadrajet carburetor
new heavy duty radiator (recored the original)
new radiator hoses
new air conditioning compressor
new air conditioning dryer
retrofit kit for R134A
new silicon ignition wires
new vacuum hoses
new rocker arm pivots
new silicon oil fill elbows
new hi output alternator
new fuel pump
Thorley headers that were swain ceramic coated
new mufflers
new SRM-4D deep cycle house battery
new passenger.driver window felts
new stainless steel rear panel screws
new A&E 18' awning
new Thetford aurora porcelain toilet
new 21 cu. pod
new holding tank and water tank sensors
new thru the bumper rear hitch(thanks Wayner Alumbaugh another netter,
beautiful first class work)
new front wrecker bar (thanks Wayner Alumbaugh another netter, beautiful
first class work)
new jabsco macerator
new cinnabar 3.42 final drive
new Ragusa welcome step
new Ragusa final drive cover
new Ragusa transmission pan
new statpower inverter
new MSD knock sensor and ignition retarder
new Leigh Harrison sensitized brake booster
new stainless steel bumper bolts
lots and lots of small parts

So the bottom line is this. If you find a really nice coach that has been painted, new interior and all of the upgrades etc for $20-30,000 it looks like a good deal, unless of course you are like me and love to work on them.

hope this helps some of you, tom


This is an alternate view of GMC ownership. (you can do this)

You can own and operate  your own GMC for nothing (relative), but you must accept 2  caveats:

1  Your GMC is only worth $6K or less on the market today.
2  You need to do your own work as much as possible --- else use our vendors

INSURANCE ($20/month)
You can buy liability insurance for your GMC (required) for about $20 per month, and self-insure yourself for losses you may incur on your GMC.  After an accident, you  will still own what is remaining of your GMC and you can move the good parts to your next GMC ;>)

In almost 70 years, I have never collected any money from any insurance company - so my view is biased.  I know several GMCers have collected on their insurance, I consider them blessed, and you will hear from them here soon.

You can pay $600 to $900 per year, for comprehensive or agreed value insurance and in 10 years you will have paid more  for insurance than your GMC is worth.  Unless you have an "agreed value" policy, the insurance company will pro-rate your loss claim to the market value and give you $6K for your loss.

GAS MILEAGE (we are not using our share)
Don't worry about it, you are going to get 8 to 10 miles per gallon depending upon if you  you tow or not, no matter what you do.
We are just  not using our share, I know young working families that are spending $200 a week, commuting to work (bless their hearts - keep paying that ssi).  Going to Pueblo will cost you less than a months commuting cost.

Depending on where you live or where you register your GMC, you can license for life ($100) with no inspections.

BUILDING YOUR GMC (this is the fun one)
I know people who cannot change a light bulb.  Owning a GMC for free,  may not be the deal for them. 

You have to do your own work to make this free.  How nice you want to make your GMC is your choice, not manditory.  Safety and reliability items are the first things to be fixed.

 Fix the things you can, if you cannot, use our vendors.

You can do this, we can help ( Bdub is our savior, with out him none of this is possible - send him a dime)

The GMC is your life, your hobby, your freedom, the link to your children, all for free, do it now.