8.1 towing

burgundyz71 · April 19, 2003

Guy I know picked up a used 8.1 Crew Cab Dually LB, What kind of fuel mileage while towing are you guys seeing ?

Shaners · April 20, 2003

My buddy with the 2500 Avalanche is getting 10 mpg's when towing... but he doesn't have the Ally tranny, just the 4L80E/4L85E tranny...

It doesn't seem to matter if he is towing the snowmobile trailer, or the 27' camper...

manytranny · April 20, 2003

Ive heard numbers as low as 7...

4x4man · April 21, 2003

We would get 6-7mpg towing our 10,000lb 5er in the mountains of Colorado when we had our 01 8.1/Alli. Our best mileage was 9mpg going around 65mph on mostly flat highway to Pueblo from Denver.

Bob

awdvkd · April 25, 2003

I pull a 18ft horse trailer w/ four horses (approx 8K) I really don't notice much difference than driving unloaded. I may lose 1-2 mpg, I drive pretty slow and patient since I tow live loads. If you don't like diesels you won't find much better than the 8.1 ally to tow with. :thumb:

HDChuck01 · April 25, 2003

I get 10-11 empty or loaded. I have a 3000 lb camper i put on the back and pull atv's behind. Going up mtn passes or flatlands, gas mileage is always the same.

tbyrne · April 28, 2003

I want some of the mileage you guys are seeing. I have two 8.1 trucks that I use to pull a 10,000 lb enclosed car hauler. The first is a 2002 Suburban with a Whipple supercharger/intercooler, long tube headers, Volant induction, custom programming, Direct Hits ignition and 22" wheels/tires. The best I have seen is 7.6. That was averaging 65-75 MPH. The other is a 2002 Silverado HD. Mods include a Comp Cam, Volant induction, Direct Hits ignition and custom programming. It runs on 35" tall tires so that makes negative impact on mileage. Best with this towing has been 7.8 (driving a little harder).

I had seen a best of 6.4 while towing. I installed the Volant and Direct Hits then saw a jump tp 7.6 on the same 1000 mile trip with pretty much the same driving conditions/style.

Mileage without anything in tow is about 11-12 for the Suburban and 8.5-9 for the Silverado.

The Duramax guys really get us in the mileage dept. I was talking to one of my delivery drivers today. He as a 2002 and usually sees 17-18 unloaded.

Tom

tbyrne · May 5, 2003

How anyone else noted any mileage changes after doing various modifications?

Tom

8100HD · May 6, 2003

Tom, Got my mods through your company, my current set-up is.... 8.1/alli/3.73rear /TOG's/DirectHits/Superchips/Descreened MAFS/UPD. With 3" b/l and 35" BFG M/T's on H2 rims. Just did a run from CT to NH this weekend, speed 75-80 basically unloaded got 12.5 mpg. Definetly not bad for a 8.1 w/35's.