Quote Originally Posted by Dq383500 View Post
I don't have enough miles on my setup to give mpg, although I don't expect it to be good. In just the little driving I have done I can tell with the 700r4 there's no way with the gear vendors I can pull double overdrive as the engine is just out of the sweet spot,
What I'm getting at is I wonder if when your in overdrive could you be off the sweet spot? I know it's a diesel but isn't their a cruising rpm that is preferable.
I was trying to get closer to that sweet spot with the overdrive transmission. With the old TH400 the engine was revving high at cruising speed of about 55mph. It really didn't feel comfortable going any faster. And with this setup I was getting 18mpg towing my Saturn SL2 on a dolly.
Now the whole idea was reducing the engine rpm with the overdrive transmission, so that I could go a little faster, with less noise and slightly improved fuel consumption.
I was aiming at like 20mpg. I agree with you as far as the "sweet spot" goes. I'll have to figure out what the best cruising speed is for the best fuel economy.
However, first I guess I have to figure out why this many gallons of fuel were just turned into transmission heat instead of miles on the road.