hey guys,
i have a 2003 yukon denali w/6.0 - 3.73 - whipple - 8psi - 44lb inj - nelson tune - walbro pump - volant ram air - trans go with servo - 22's - 31.6 in tall tires... just cant deside to go ahead and do it... any info you could spare me would be great...

 

I would stick to 4.10's. They are more highway friendly.

 

Yeah I think 4:56's would be way to much IMO! 4:10's should be enough and would do the job!

 

what do you think it would do fall off on the top or what - it seems like some gear would complement my package but it is too expensive to do it twice. i have to do the right thing the first time. what do you think my rpms would be at 75mph - basicly i want this thing to be quicker and not sure what the answer is. like i said i was thinking 4.56 & 2800 stall. this is my daily driver though.

 

4.56 gears and a high-stall converter in a supercharged heavy ***-ended SUV is a heap of fun. This, I can assure you.

For your tires though I agree with other in that 4.10's would be the best gear for you. Another thing to consider that the higher the numerical ration is the smaller and less teeth the pinion gear is. Tooth-to-tooth contact surface area is reduced as that ratio increases. The more gear ration the more torque multiplication too. Denalis have 10-bolt rears with the 6.0, not a 9.5" like the pickups. That rear end needs to be babied as much as you can do it.

 

Your problem is not the gears it's a huge heavy vehicle and a little engine. 456 gears are for racing not highway driving. You would be sorry.

 

I Run 4,56 Gears And With The 5.3 Dead Hook With 1.64 60' With 26 M/t Drag Radial,crossing Around 6700 To 6800.i Never Ran My Street Tires But I Also Have 31.5 Toyo Porxen @ 57 Mph Tuning 2000 Rpm.just To Give You Heads Up.

 

that's not bad for some 4.56's. i run some 4.10's with a 29.75" tall tire turning 2000 @ 58mph