Gear ratio for oil field work pulling tanker?

Its the mechanical math behind how your truck turns diesel into locomotion

Some iinsight is learned through driving poorly specced vehicles vs correctly specced vehicles.

Then you can play with the math to discover better and worse combinations of transmissions engines tire size and reaar end gear ratios based on desired engine rpm.

Your questions are altogether too rudimentary and lack too much basic mechanical knowledge for good answers.

Its like a 1st grader who understands only addition and subtraction asking why a quadratic equation describes a parabola in a cartesian plane. You know the words, but are trying to shortcut 4 more foundationnal years of concepts

 

Pulling frac pumps,we had OW permits to 120,000 lbs.

 

If your current setup handles the job site terrain the on highway performance won’t make much difference on pulling power . The major difference is what gear you do it in .

 

Primarily off-road, 3.90s. Would even work with a small engine. With 550HP, 3.90s and a set of lockers would be able to change the rotation of earth.

 

i wouldn’t assume anything these days

 

I would look at your specific trans, look at one of those gear ratio calculators on the internet, and try to keep the torque in the lower top gears around 1200 RPM, which is the peak torque for the 6nz.

You need to keep the RPMs around peak torque, which means if you are driving an 13/18 spd, you should do it in direct drive or near it to maintain a hill climb.

You need to take a course in basic mechanics. I learned about them in 5th grade.

 

Let it ride…… changing the rear gears is kinda costly and your return on investment blows .

 

He’s right. The only way I would do a gear swap would be for 3.90s, 46k rears and full lockers with it. All or nothing, not just a ratio change.

 

No need to change it if that tranny is OD. Is first on the low side too high?