what size tire with 3.73's??

[moregrip]

What is the largest size tire you would put on a truck with 3.73 gears without stressing the drivetrain to much? Also the same question but with a supercharger added to the mix?

My options are 33", 34", 35" instead of the stock 245/75-16's.

[Ben]

GM diff ratio's are all about 10% difference going up or down.

 

So take a look at the percentage difference in tire dia from 30". That percentage difference will EFFECTIVELY change the diff ration same amount.

 

Also means same percentage loss in power due to the change in diff ratio (lower numeric).

 

Then factor in the loss of power transmitted through the U-Joints, as you'll have to lift and if suspension lift, higher U-Joint angles...less power transmitted.

 

Plus the higher frontal area...aka wind resistance.

[moregrip]

I don't want to swap out the gears. I would like to stay with the stock 3.73's.

 

I'll probably go with a rancho 4" lift which is pretty conservative.

 

I'm still up in the air about the s/c.

[Machine]

Without a SC - 33's

 

With a SC - 35's

 

I had 35's on my 2500HD D/A and it was a dog until I started making big performance mods w/out regearing. I was able to increase performance and overcome the tire change by adding the Edge Juice and Quad Box (135+ HP) to my Duramax - that would be like you adding a supercharger to your gasser.

 

I now run 33's with the Juice and the truck is very fast with stock gears. With the truck set at stock the acceleration is still good.

[PFarkas]

without stressing the drivetrain to much?

 

How much stress the drivetrain sees depends on how much stress you put on it. If you drive like my mom, you could go larger than 35", never over-stress the drivetrain, and probably not notice the hit in maximum accelleration. If, on the otherhand, you drive like me, you'll be making everything work pretty d**n hard some of the time (ok, a lot of the time).

 

If I could have gotten approval from my wife, I'd have left my stock 3.73s in and gotten the supercharger when I put on the 35s and the lift. I liked the idea of lower engine RPMs and more power. I still like the idea.

 

You've got the 1500HD, which is the same as a 2500LD, which has a larger diff than the 1500s. I have been told that the 14bolt FF diff (an option for the 1500HDs and 2500LDs) is up to the task of a supercharged engine, a 3.73 ratio, and big tires.

 

 

In any event, 35s and 4 inches of lift for your truck may not work out. I had to add the 3 inch body lift to eliminate tire rub when the front suspension was compressed.

[moregrip]

Actually I really like the idea of keeping the 3.73 too.

I know this might not be a popular idea (4.10's, 4.10's, 4.10's) but check this out.......

with a supercharger and 33" or 35" (since 34's are so d**n hard to find)

I 'm hoping to signifigantly increase off the line acceleration (0-60mph) while turning

approx 2000 rpm at real freeway speeds (i.e. 70-80mph) instead of the 2700rpm

with the 245/75-16's for better than stock highway fuel economy (long trips)

 

PLUS! be able to light-med off road occasionally.

 

so the plan goes like this:

 

1. Radix Supercharger

2. TOG Headers, Borla Cat Back Exhaust

3. Transgo Shift Kit, Yank high stall converter

4. Stock Rear End (AAR 9.5" 14 Bolt) with stock full locker

Note: I could always upgrade to the AAR 10.5" if it breaks.......

5. Stock height with 33" tires (285/75-16 or 285/70-17)

or

Rancho Lift with 33" tires (33x12.50-16 or 33x12.50-17 or 325/60-18)

or

Rancho Lift with 35" tires (35x12.50-16 or 35x1.50-17 or 325/65-18)

 

What would this run in terms of $

Lucky me, I got the approval code from the wife for a specified $ amount

and I'm just wondering what you all think of the above senario.

I really like the looks of the 18's as they would let me run a big brake kit too.

BUT!

In terms of light-med offroading how do they hold up?

does someone have some experience with their offroad worthiness?

It wouldn't be worth it to me, to go offroad once and mess up a rim, on

the other hand how agressive can you get with a crew cab w a 6' bed?

any advice is appreciated....