Bill... my intended tow vehicle for my '48 Airstream 'Trailwind'
work-in-progress is a 1949 Willys-Overland 'Jeepster' which is undergoing
its second re-power in some 30 years... it now sports a 350 tbi v-8 engine,
700R4 transmission, and the rear axle is a 9" Ford out of a '77 Lincoln
Versailles... these differentials were in use in a wide range of
Ford/Lincoln/Mercury vehicles for about 28 years, and could have all sorts
of gear ratios swapped in... the one i'm using has a 3.89:1 ratio, which
should be more than sufficient for the Trailwind, which will weigh in, dry,
at around 3500 lbs...
the highest gearing for the 9" was 2.50:1, i believe... when you find your
car, you can look at the i.d. plate on the differential, and the number will
include the gear ratio for the lowest gear - '250' or '389' or somewhere in
between...
if you don't want to add a leaf to the rear springs to stiffen the ride a
little bit, you could add an 'airbag lift', some of which can be pumped up
or down from a switch on the dash...
tuna
reno, nv