Rear axle ratios
I've had a hard time finding a truck with everything I want on it, so I'm debating the need for higher rear axle ratios. Here are the net 1st gear ratios for various half-ton trucks: Make Rear ...
Forum Discussion
hemismith wrote:blt2ski wrote:
What are the tire diameters. As that can make a difference too. A 2" diam change is like going from a 3.73 to a 4.10 if you go smaller, or a 4.10 to a 3.73 if you go to a larger tire.
I'm just considering stock tire diameters. If I were to change up to large off road tires then I think a gear change would be important.blt2ski wrote:
Also torque plays a part in the take off part too.
Exactly. So as a rule I'd expect turbo-charged engines not to need to much gearing because of their low-end torque. For some reason though the 5.7 Hemi felt faster off the line than the Ecodiesel even with the same transmission/rear end ratio and with less torque down low.
You need to look at the stock diam of tires from EA manufacture, even from with in manufactures. One may have an 18" rim, another a 20" rim. They may or may not be the same diam. ALong with the 20", is also possible depending upon the sidewall ratio to be smaller in diam. Some like the 265-75-16 and a 265-70-17 are literally the same tire, just a different rim size to handle larger brake setups. Many GM's have either a 31, 32 or 33" diam option, depending upon the size. A 31" setup with the 3.73 gears will be on par with a 33" diam setup with 4.10's, No difference in shift points assuming the same motor, trans etc.
Stock or not, the tires may be different diameters!
Marty
