this is weird question but i am going to throw it out there. when you do a rear end ratio change, that doesnt mess up your rpms does it. i am wanting to know if my converter is slipping excessily and i am doing formulas that i got from school and with my ratio and my tire size, it says that i should be running a higher rpm than what i actually am. what is a way to see if it is reading right.

For all of you that are running a 700r4 and have 3.73, what is your rpms at 60 mph?

 

you do not know if ur tachometor is right? it does change your speedometer you need to change the gear in the transmission for your rear gear ratio and tire size if you havnt done that it's the problem.

 

2000 rpms, wish i had 4.10s

 

No ive changed my speedo gears so i know that my mph is right. Thanks abyliks, i didnt want to state my rpms and make anyone kind of sort of agree with me if u know what i mean and make them second guess thenselves and agree with me. This way by making u state it, i dont influence your answer.

 

well, thats providing my tach is accurate

 

it should, mine seems accurate. if we could get more guys to say and join in then we will know for sure.

 

not 100% sure what you're trying to ask, but no it doesn't mess up yout RPMs. your engine will only run at or max out at one place regardless of the gears in the back.

 

Your rpms should be around 2100 at 60mph with stock tires (245/50/16), 3.73 gears, and transmission in overdrive. If you did not change the speedometer gear when you swaped the axel gear this will cause you speedometer to be off which could lead you to believe that the rpms are off. Also that rpm is with the torque converter locked. If you torque converter is not locking for some reason the rpms would be ~300rpm higher. The torque converter should lock automatically when in overdrive with your foot on the gas and driving at a constant speed.

 

then it must be pretty accurate then, i am running 225/60/16