Thread: too much stall

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I don't drive in the winter months, because it is still rust free. I do know that it has a 3:08 gear.

Originally Posted by tominiowa

I don't drive in the winter months, because it is still rust free. I do know that it has a 3:08 gear.

Tom, that's your problem. Assuming that you indeed have a 700R4 the tranny ratios are 1st 3.06, 2nd 1.62, 3rd 1.0 and 4th 0.70 OD. Running 38.5's and 3.08 gearing you've got to get up to almost 20mph before you're into your torque range. It runs out that you're only doing about 1300rpm at 70mph! You need to get a much lower gear in the truck - you're really straining your tranny as it is. I'd probably go at least 4.88's, but 5.13's or even 5.38's are not too much, depending on how you use the truck. Points of reference, consider 70mph cruise, assuming a 700r4 OD, 4.56's turn 1950rpm, 4.88's turn 2087, 5.13's turn 2194, and 5.38's only crank 2300rpm at 70mph. Drop in a pair of new ring & pinions and get that gearing where it needs to be and it'll be a whole new truck. You're gonna love it!!