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n33k0 · 10-28-2015, 01:30 PM

How tall are the rear tires on your truck? I have a TH350 with 4.10 gears, so my setup shouldn't be too far off yours; with 28" tires in the rear (275/60r15) I calculate around 3000 RPM at 60mph. I don't have a tach, but that number is consistent between multiple online RPM calculators.

Either way, a lower (numerically) differential gear will get you the biggest bang for your buck. For the price of a gear vendor O/D, you could get yourself a proper 4 speed O/D transmission (200-4r, 700-R4). Taller tires will help a little, too.

10-28-2015, 01:30 PM	#3
n33k0 Registered User Join Date: Sep 2014 Location: Florida Posts: 184	Re: Revving too high How tall are the rear tires on your truck? I have a TH350 with 4.10 gears, so my setup shouldn't be too far off yours; with 28" tires in the rear (275/60r15) I calculate around 3000 RPM at 60mph. I don't have a tach, but that number is consistent between multiple online RPM calculators. Either way, a lower (numerically) differential gear will get you the biggest bang for your buck. For the price of a gear vendor O/D, you could get yourself a proper 4 speed O/D transmission (200-4r, 700-R4). Taller tires will help a little, too. Last edited by n33k0; 10-28-2015 at 01:37 PM.