6 Speed Auto And 3.73 Rear

[lazer]

I have the 4 speed auto and 4.10 rear in my 05 HD. I'm looking at a new 08 with the 373 and 6 speed auto. Will I get better gas mileage? i'm getting 10mpg now. Can't get any worse can it.?

[2017HD]

I have an 07 HD with a 4.10 and after 7,000 mi am averaging 14 MPG (dic). In 6th gear 60 MPH is around 1900 RPM which give me enough torque to move both the truck and my 5600 lb TT down the road. I thought about getting 3.73s when I ordered mine, but the fleet manager suggested that the 4.10 would give better performance when towing esp with all the hills I have to contend with. He was right, the sweet spot for the engine is between 3 and 4000 RPM - which with my setup is 50-60 MPH in 4th gear. So I can climb my hills with ease. I think with the 3.73 I would have to resort to 3rd gear and put up with a slower climb. I like being able to tow in 6th when on flat hys. I also like the grade brake and the tow/haul mode. BTW you can get more drivetrain information at www.gmpowertrain.com including HP and torque curves, gear ratios etc.

[2007 GMC HD]

I got the 3.73 gears in mine and it is getting 16 mpg when not hauling. It gets about 11 hauling a 7000 # trailer. It climbed the hills of Wv with ease, even on crappy Route 33 with all the switchbacks on it. I do have just the reg cab so it doesn't weigh as much as say a ext or cc.

[2017HD]

I should also note that I have a 4x4.

[sonjaab]

My 07 x-cab 2500 4x4 6.0 3:73s gets a real 13.5 mpg city stop n go driving

with the ac on. Calculated by fill ups with gallons used and miles traveled.

 

Haven't done any hiway trips so can't tell ya highway mpgs.

 

My 04 x-cab 2500 4x4 6.0 4:10s got 10 mpg. city 17 hiway

[cbmotorsports]

Wow, I wonder how I am getting 12-13 city with my 04, 6.0, 4x4, 4.10's, with the hypertech programmer on 93 octane. I guess mine isn't doing so bad. My right foot isn't very nice either. Watch not that I give it credit it will go through the floor on me.

 

 

 

 

 

 

Bones will heal and machinery can be fixed,

but regret will never go away.