My $0.02: Was told that my Yukon had 3.73s, but found that was incorrect. My '02 yukon came with 3.42s. Proved with gear specs (trans & rear). At 70mph, RPMs are dead on at 1900. Thought about upgrading to 3.73s on it, but my wife drives it daily. Due to gas prices, I drive an '02 Accord on 50-mile, one way commute.

Now... My '86 C10 came stock with 2.73s. Those'll soon to be 3.73s. Looking for better acceleration (less work on engine & trans), and hope to be close to Yukon's RPMs at 70mph. I'm thinking 3.73s will result in 2000 RPM at about 63 - 64 mph, using 275/60R15s. Close enuff for me. I'm looking to drive this to work once or twice a week. My goal was to have a nice custom project with fun driveability. It'll definitely hit NPR's pavement when complete.

 

I search and lurk more than I actually post, so I'm easy to miss. I live up on the Northeast side of town, I'll try to make one of the GTG's one of these days, but my weekends are basically booked up until I retire.

 

i wish i would have gotten at least 3:90's instead of the 3:73's i got. i had 3:42 factory and i couldnt really tell a difference in anything except my wallet to pay for the gears. truck still runs the same time and gets the same mileage. when i put a locker in it im going with at least 4:10s. also i hardly ever drive my truck anymore

 

I feel your pain man. I too have the 3.23s. I will be switching to 3.73s if I keep my truck long enough.

 

get a set of 4:10s and ill trade you

 

I may have missed it, but what size tires do you have?

 

Still running the stockers, 245/70/17's that works out to 30.5 in tall. Anything I switch to will keep the same overall height.

 

Did you make a decision about the gears?

 

The best set of toleranced matched gears are going to be straight from GM.
Other aftermarket gears have shown to give gear wine even after shimming to the propper clearances.
Many mechanics have told this to me. Four Wheel Parts and NTB to name a few.

Jim

 

I'll probably be going with the GM 3.73's. Does anyone have the part number on the ring and pinion set?