Gear ratio 95 yukon

[rongamliel1990]

Hi there, my name is Ron and i own a 1995 GMC yukon 5.7 v8 and i need to do a front axle swap. is there any way to determine what is the gear ratio if both the plates on the axles and the RPO codes in the glove box are missing?
HELP please!

[Jsdirt]

About the only ways are to either physically count the number of teeth on the ring, and pinion, then divide the 2, OR, mark the driveshaft with a white paint pen or piece of chalk where you can easily reference it, then mark the tire the same way (12 o'clock is what most do) - now spin the wheel one revolution and count the approximate number of turns of the driveshaft- this will get you in the ballpark. If it spins 4 times and the mark on the shaft ends up just past your reference point, then you have 4.11 gears. If it spins 3 - 3/4 turns, you have 3.73's

[rongamliel1990]

Thank's a lot for your help!

Well i've already removed the rear axle cover and i found the numbers 41x11 on one of the rings. I guess it means that the gear ratio is 3.73?

[Doug_Scott]

Something to be aware of when using the turn and count method, if one wheel is on the ground being held stationary, turning the driveshaft one turn will result in the wheel turning either half or double (I forget which one it is, but it will be obvious when you try it) what you expect. I seem to recall being told decades ago that spinning one wheel on ice may show 50mph on the speedo, but the tire is actually going 100mph, when the vehicle is stationary.

 

It is better to turn the driveshaft 10 turns, and count the tire rotations. Doing this will allow you to be able to easily tell the difference between 3.08 and 3.23, or 3.23 and 3.42, or 3.42 and 3.73 or 3.73 and 4.10 ratios.