figure out what the axle ratio is in my truck?

Thanks

 

Use the speed versus RPM trick

I've been told that with stock tires and the 48RE, at 75 MPH your RPM's should be around 2100 for 3.73 rears and slightly over 2400 for 4.10 rears. I tried it on my '06 and the speed and RPM's were what they were supposed to be, and I know it has 3.73 rears so the info I was given seems to be accurate.


Kris

 

Also, there should be a sticker inside the glove box that has the ratio on it. Another way is to get the build sheet from a dealer that has all the options and stuff.

 

See this thread about gearing. https://www.dieseltruckresource.com/...s-t266884.html

 

Jack the truck up and put it in nuetral.Put a mark on the inside of your tire,as well as a mark on the drive shaft.Twist your drivehaft by hand while under the truck and count how many times it goes around per 1 revolution of the tire.You most likely have 3.73 or 4.10.So anything close to either of them numbers will be what it is.Although the sticker in your glove box is easier.

 

Thanks. Didn't come with stock size, so that one is out... I'll go check the glovebox, and only after the ground dries will I try the axle rotating trick...