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[VAC] Re: Towing With A Short Wheel Base Tow Vehicle



Greg,
 I have training and experience in the difference between HP and torque
and know full well that torque by itself does absolutely nothing, only
HP does "work".

However, I've towed our present trailer with a 1/2-ton Dodge P/U,
powered with a 360 V8 *and* with a 3/4-ton Dodge P/U with the Cummins
T.D. I know that the latter is only 160 HP, but has over 400 ft. lbs. of
torque. Although I don't know the details on the 360 V8, I'm sure that
it's more power and less torque.

Both trucks have a 3.54 axle ratio.

The 1/2-ton truck required towing with the O.D. locked out, running the
engine at about 2000 rpm at cruising speed; the 3/4-ton can pull in
O.D., running about 1700 RPM at the same speeds.

I found hills on which the 1/2-ton couldn't hold 55 MPH, even in 3rd.
With the 3/4-ton, most hills could be pulled at 60 MPH in O.D., and I
found none that I couldn't hold 60 on after forcing the downshift to
3rd.

AT 60 MPH, I can mash down and she just accelerates, the 1/2-ton would
do that also, but had to be in 3rd.

There IS something to this "torque" thing. <<grin>>

All of that beside, the 3/4-ton feels much better in front of the
trailer, definitely more relaxing to drive.

Point of reference: our trailer weighs about 6000# when ready-to-roll
and we have maybe another 1000# or so in the bed of the truck and our
own weights. GCW is 12,400#. GCW with the 1/2-ton truck would have been
about 11,800#, loaded similarly. Fuel mileage is half-again as much with
the T.D., 15 MPG vs. 10 MPG with the 360 V8.

                                      <<Jim>>