I Know The Hp But......

05GMC4DR · August 29, 2008

How much Tourque does my motor have (LM7 5.3 Iron block). Ive got 3.23's in it according to the build sheet and I was thinking about going to the 3.43's and was curious as to what kind of torque differences there would be.

Rob

J-man67 · August 29, 2008

335 ft lbs. Honestly a change from 3.23 to 3.43's isn't going to make much of a difference at all. I would go with the 3.73's. You will feel that. Also, the gears don't provide more torque, they just apply the torque to the wheels differently.

Zembonez · August 30, 2008

335 ft lbs. Honestly a change from 3.23 to 3.43's isn't going to make much of a difference at all. I would go with the 3.73's. You will feel that. Also, the gears don't provide more torque, they just apply the torque to the wheels differently.

+1 3.73 if you want any real difference.

2000DV4.8 · August 30, 2008

335 ft lbs. Honestly a change from 3.23 to 3.43's isn't going to make much of a difference at all. I would go with the 3.73's. You will feel that. Also, the gears don't provide more torque, they just apply the torque to the wheels differently.

+1 3.73 if you want any real difference.

+2 Your mileage may actually go up if you do a lot of city driving, or drive in hilly areas.

05GMC4DR · August 30, 2008

I know that the gears affect the way the power is put to the ground. I do alot of mixed driving and I thought that the 3.43s would a little better mileage then the 3.23s. What kind of mileage are you guys getting with your 3.73's in the city/highway/towing???? Thanks for the help.

Rob

2000DV4.8 · August 30, 2008

I was getting about 16.5 mixed, 18 highway stock. Now with the bull bar, mud tires, and the torsion bars cranked up about 1.5" I'm at 16 mixed, 17 highway. Keep in mind, the truck also has 171k on it.

3.73s are the best all around gear, especially if you're going to tow at all.

Deichler · August 30, 2008

I have an 08 reg cab LB Silverado and have the 5.3L with AFM and get 20mpg steady. When running E-85 I drop to 16mpg. That is average on the DIC. Also, I have the 3.73 gears and 4x4, 17 inch wheels.

05GMC4DR · August 30, 2008

Mines a 2wd with the 5.3. I get anywhere from 13 to 16 city and 18 to 19.6 highway. Anyone towing with 3.73s?? What kind of milage are you getting?

Sean111 · August 30, 2008

I know that the gears affect the way the power is put to the ground. I do alot of mixed driving and I thought that the 3.43s would a little better mileage then the 3.23s. What kind of mileage are you guys getting with your 3.73's in the city/highway/towing???? Thanks for the help.

Rob

I have 3.73s in my 02 Z71, I regularly get 21MPG on the highway, and 15 around the city. Should improve slightly with the electric fan kit and Hypertech goodies on the way.