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3.08 to 3.73

708 views 1 reply 2 participants last post by  Rambodog  
#1 ·
I have a 2011 gmc Sierra z71 that has been whinning in the front differential since I bought it. In the last month it has gotten worse. I did a service on the front diff to find metal. I just bought a rear ring and pinion and bearing kit 3.73 ratio. I have a couple of questions.
1. What is the rear size? I have been getting 8.5 and 9.5 as an answer.
2. What is the front diff size? I have been seeing
3. Do I need to change the carrier in the front diff to accommodate the ratio change?
I tow very seldom with my truck so the 3.73 is a good step up since it's went bad.
 
#2 ·
Welcome to the site!
Front is 8.25 and the rear is 8.6 unless it's a 6.2 with Max trailering. The 8.5 hasn't been used since 1999.