mpg CAT 3208T & Allison 4spd?

[Brian Johnson]

Hi folks.  We purchased a used 1990 Beaver Contessa 37' w/90K miles, a CAT 3208T and Allison 4 spd trans earlier this year.  Does anyone know what kind of mpg these average?  I haven't really driven it far enough yet to check, but am planning a trip, and would like to calculate est. fuel costs.  I live in the western US, so there are a lot of up and downs!...  i.e. not many flat highways.  Don't plan to tow anything right now, but averages with and without a dinghy or boat would be helpful.

Thanks everyone.

Brian Johnson

[Edward Buker]

Brian we had an '89 Contessa with the same engine and transmission, but towed a 3200lb Honda Accord. We averaged about 9.3 to 9.6MPG at 62 MPH which was our cruising speed while towing. If you push the speed much beyond that, the RPMs are up pretty high, and the mileage dropped quite a bit.  It was a good motorhome given the era, but the 4 speed transmission limited the top end speed somewhat.

Later Ed

[Mandy Canales]

Brian...We have  a 40' '90 Marquis with the same configuration.  Our coach weighs about 30,000 lbs and tow a '91 Honda Civic.  We also have 200K miles on it.  Our average mpg is 7.7 over the past 4 - 5 years.  I believe the Contessa is lighter in weight so it should get a little better mileage.  Sometimes a valve adjustment and a little use of Lucas Oil additive may also give you a 1/2 mile per gallon more.