Gear Ratios with diesel

IceSoldier88

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How come with the diesel engine the highest gear you can get is 3.55. Isn't a higher gear better fro towing and turning bugger tires?
 

PapaRaptor

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they must have it figured out with the transmission gears and tire ratio.
Seems to work very well. no complains here.

in the old days the trucks with the 4;10s could only run about 78 mph then they ran out of rpms. A lot has changed since then
 

davidb1841

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The engine is so massively powerfull, and with a 10 speed tranny, you just do not need the lowest gear in the differentials. So keeping the rear end at 3:55 can significantly improve the MPGs over lets say a 4:10 or 4:30.
 

Whyte Rhyno

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Doubt a lower ratio is needed. The truck has so much torque anything lower than 3.55 would be overkill and would affect mileage. I've climbed hills pulling a trailer in 10th gear on more than a few occasions. Unless you went to 40" tires I don't think you would need anything more
 
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