New Rear End

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Jeff Geist

Active Member
Joined
Jan 30, 2002
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Location
Royersford, PA
136K miles on my 02 and started getting some grinding noise from the rear. Took to local shop that does my inspections and they tell me $2500 to replace rear diff, wheel bearings, etc. After reading some posts on the site, I went to local specialist and I'm looking @ $1200 with parts from a junkyard ($700 for 95K rear and $500 for labor). I have a 4.10 even though I thought it was a 3.73. The 3.73 is cheaper. Is it possible to change over to a 3.73 like I've read some people try to do. What are the advantages/disadvantages?
 
your profile says your truck is 4x4, so you will need to change out the front and rear axles if you go with a different ratio. 2500 is ridiculous, and 1200 is still too much in my opinion. check your local craigslist for an axle.
 
Mike - it is a 4x4 and that's what I was thinking that I would have to do the front as well if I went to a different gear ratio. I'll give craigslist a shot. Never had a major issue with this truck in 11+ years so this is unchartered waters for me.
 
I had the same issue on my rear end of my 04. With the 4.10 and LS, I took it to local shop where they said I need the whole setup. I didn't believe them cause I wasn't that hard on my truck then. So went to another shop, they took it around the corner and said I probably just need the LS additive. Replaced the oil and added the additive and presto all better.



2nd thing, I got a quote for 4.88s and the shop quoted me 2k with yukon gears and new everything. That's both axles. so the $2500 seems quite steep unless you really messed something up, and if it was that screwed up you probably couldn't drive it, imo.



The 3.73 gears are great if you don't really plan on off roading and stay on pavement 95% of the time. But you will also have to do the front ring and pinion. Best bet is get a used 4.10 ring and pinion out of a 8.8 of CL, bunch of people do that when they upgrade. Then you can keep your LS if you have one.

 
I would stay 4;10. If you dont have LS. And your ring and pinion are good. It might be the spider gears. Simple DIY repair. If it is the LS unit is diy also.



Pinion bearings and ring gears I leave to others, for proper backlash.
 
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