Re: [VAC] transmission coolers-

["Dr. Gerald N. Johnson" <geraldj@xxxxxxxx>]

If you want the manual transmission to run cooler and the truck to haul
better, go visit a drag type hot rod shop and change the rear axle gears
from the factory economy to something made for more rapid launches. My
F-150 is much livelier with 4.10 than 3.08 and gets exactly the same gas
mileage. That little overhead cam V-8 loves to turn fast and that's
where it develops its torque and horsepower (Hp rated at 4850 RPM, I
think). The stock gears cruise at 1500 rpm at 55 mph, almost lugging
range and this engine doesn't lug well. In the process the torque load
on the transmission is reduced for the same load in and behind the
truck. I think Ford should have built this truck with the 4.10 gears
instead of 3.08... But they are worried about mileage when used to haul
driver alone in city traffic, not the capability of doing WORK.

You can also get more thrust to the ground by going to smaller outside
diameter tires at the cost of ground clearance. On my Ford going from
the current 29.1 to 26" diameter tires would cost 1.5" of ground
clearance and have the same effect as changing the 4.10 to a 4.56. I
could have achieved the same original thrust change by going from 29.1
to 20" tire diameter with no gear change, but at the cost of most of the
truck's ground clearance and some load handling capacity because the
very low profile tires aren't rated for as much tire load as the fatter
tires.

The gears for my Ford cost $480 installed. The speedometer gear cost
about $25 once I found one in captivity. There are also electronic boxes
for speedometer correction in the computerized trucks and cars for $88
to $123. If I start playing with tires I'll add one of those because I'm
at the limit (maybe 3% beyond) of simple sensor gear ratio change. I
have no idea what parts might or might not be available to make such
gear changes in Toyota trucks. A hot rod type trucking magazine might
have some hints, the dealer probably wouldn't unless he actively races
the near stock trucks.

Gerald J.