Dudes the Yukon Denali comes STOCK with 3.90's or 3.93's i cant remember which ones. But they have to be OEM right??

 

Blackerado,

I have never seen any OEM gears in the 3.90 ratio. Not to say they're not out there, But I didn't see them when I got mine. I did Upgrade from 3.42's to 3.90's. This was one of the first mods that I did to my truck and was having a hard time decideing between 3.73 and 4.10. The gas mileage difference between 3.42 and 3.90 is negligable at best and my mpg has actually increased with the addition of my cam. I am averaging about 18-19 mpg now.

Don't expect this to be a magic bullet though. I did this expecting to gain huge amounts of lowend and not really knowing much about the torque managament system and all. Don't get me wrong, I'm glad I did it, I actually have been thinking about upgrading to 4.10's lately, and when I do an Eaton Unit, I may very well do it. But it will be a while.

 

3.90's are available on Dodges but not GM
available GM ratios for the trucks are
3.23
3.42
3.73
4.10

 

I have 3:73's in my Tahoe. I am running 24" tires and can tell the difference from stock tires. I have an Eaton and 4:10 inbound at this time. Hope to get them installed next week. I figured 3:90 wouldn't make any difference and with the tall tires the 4:10 will get me back to a stock gear size feel even with the bling bling.

 

Do the 4.10's, you will be happy. I am considering a 4.10 swap for my truck.
You can get 3.90's for these trucks, but they are Richmonds not OEM. I think Precision gear used to make them also, maybe US gear. Not a very popular ratio though because they are so close to a 3.73 and there are no 3.90 front gears available for the IFS.

 

Not really, you be surprised. It's all in what tire size you run.

 

i've seen a ford with a 3.90 stock, but i've never seen a dodge with one. i've only seen a 3.91 and 3.92 from dodge.

 

my buddys 04 silverado has 3.70 gears stock lol, mebbie they made a slight change in 04?

 

I would think the 3.73's would be plenty with a 29" tire. If you're just going for all out performance then just go 4.10's and don't look back.

 

i just installed 373 and dont feel the difference at all. i wish i would have gone with 410s.