I'm a little disappointed in my gas mileage. I keep hearing claims of
10-12 MPG from some GMCnetters, but all I can manage is 8.47 MPG. I had the
carburetor recalibrated in the Spring by Cinnabar after having exhaust
manifold work done by them. Since then, I've kept track of my mileage.
Miles MPG Gallons Fuel Cost Avg/Fuel Cost Fuel Cost/Mile
8,044 8.47 949.89 $1,174.88 $1.237 $0.146
Doc wrote: I have a 23 ft. GMC and had the carburetor and distributor
worked over
and headers installed last summer. I get 8.7 mpg now.
Richard & Doc: Gas mileage is one of those challenges that interest me.
I've figured that if I put 100,000 miles on the coach and can improve the
mileage from 8 to 12 mpg, it should save me about $7000 (assuming slightly
increased prices). Given that one of my grand schemes (or is that a
fantasy?) is to ship it to Europe for a year and travel about, it could
mean significant savings to reach the goal (given the price of gas on the
continent). I have a 26 foot coach which I am gutting and trying to keep as
light as possible with the hope of reaching this goal. When talking with
Jim Anstett about shocks, he mentioned that a friend of his (Ray Curtis)
recently got 12-13 miles per gallon on a trip that they did together when
he only managed 10mpg. The difference: they both drove 23 footers but Ray
had the 403 engine while Jim has a 455. As they are both keep their coaches
in superb shape (Jim put in a new engine last year and Ray runs an
automotive shop that specializes in GMC's), I suspect that the solution is
to the lighten your coach and run with a 403.
Vic Marks
Vancouver, BC
10-12 MPG from some GMCnetters, but all I can manage is 8.47 MPG. I had the
carburetor recalibrated in the Spring by Cinnabar after having exhaust
manifold work done by them. Since then, I've kept track of my mileage.
Miles MPG Gallons Fuel Cost Avg/Fuel Cost Fuel Cost/Mile
8,044 8.47 949.89 $1,174.88 $1.237 $0.146
Doc wrote: I have a 23 ft. GMC and had the carburetor and distributor
worked over
and headers installed last summer. I get 8.7 mpg now.
Richard & Doc: Gas mileage is one of those challenges that interest me.
I've figured that if I put 100,000 miles on the coach and can improve the
mileage from 8 to 12 mpg, it should save me about $7000 (assuming slightly
increased prices). Given that one of my grand schemes (or is that a
fantasy?) is to ship it to Europe for a year and travel about, it could
mean significant savings to reach the goal (given the price of gas on the
continent). I have a 26 foot coach which I am gutting and trying to keep as
light as possible with the hope of reaching this goal. When talking with
Jim Anstett about shocks, he mentioned that a friend of his (Ray Curtis)
recently got 12-13 miles per gallon on a trip that they did together when
he only managed 10mpg. The difference: they both drove 23 footers but Ray
had the 403 engine while Jim has a 455. As they are both keep their coaches
in superb shape (Jim put in a new engine last year and Ray runs an
automotive shop that specializes in GMC's), I suspect that the solution is
to the lighten your coach and run with a 403.
Vic Marks
Vancouver, BC
