When people talk about “effective gear ratios” what they are trying to do is find out, given two trucks that are otherwise equal (same engine, same transmission, etc.),
what differential ratio would be required to make them move at the same speed when they are in the same transmission gear and at the same rpm. In this case that can be calculated by multiplying the gear ratio you want to compare by the difference in tire diameters (it’s actually circumference but the diameter works because math). Not sure how much of my work you want me to show but say you want to compare a tremor diesel (35s and 3.55) to a regular f250 diesel with the lower ratio (33s and 3.31) and you want to know, how much would I need to change the diff in the tremor so they run at the same rpm at 75 mph? We would do (35/33)*3.31=3.51. Interestingly, the lower diesel ratio f250 ends up being roughly equivalent (3.51 vs. 3.55) to the tremor with its larger tires. These trucks would run at roughly the same rpm at 75 mph and would exhibit similar acceleration performance (given wheel/tire combinations with equivalent grip and rotational inertia).
Getting back to your question, the tremor has an effective ratio of 3.31 when compared to a super duty diesel on 33s. Conversely, if you wanted to regear your tremor to perform like an f250 on 33s with the 3.55 rear, you would need to regear to 3.765.
If you are a masochist and would like to talk about final drive ratios, how much force is being put to the ground, peak torque, peak power, etc. you can message me. I could probably type here for a good hour
