Switched back from Redline to Motorcraft...
 

And the transmission actually feels a lot better. With the Redline, the truck felt more sluggish and got about 2mpg worse. I didn't feel like paying $150 in transmission fluid and flushing it myself. Had a $20.00 off coupon from the local Ford dealership and took it there, $130.00 total.

Anyone else notice this?

Here's hoping I don't overheat the stuff though...

I've been telling people you can't do better than oem fluid for years. your transmission will thank you for it.
Alan

HI!... Thats weird. My built 4R70-W runs better with the REDLINE D4 fluid. :fyi:

You sure you're just not feeling the $160 you just spend on fluid? :D

I know that my mileage has gone back up to the 17-19mpg (this tank may hit the magic 20mpg mark) I saw when I first got it. On Redline, I usually saw between 14-17mpg...

Of course, it could be the built transmission just likes the D4 more...

Did they use aftermarket frictions or OEM dynax?
Alan

HI!... ALTO frictions/steels. :fyi:

BTW, this tank ended up at 19mpg...

HI!... BTW : I get 21.3MPG, on the highway and I have 4.10 gears and 28" tall tires. H.P/TQ level in SIG below. :D

That is the difference. You have standard old style paper, OEM 98+ 4r70w's have dynax high carbon/graphite linings.
Alan

HI!... ALTO reds actually. :rocker: