Just for general info...

BrokenBoots · October 17, 2003

I have a 2003 Rado 3500 2WD 8.1L Allison. For the most part I drive it unloaded and I don't pull anything. Mostly around town driving.

In 13,000 miles I have averaged 9...nine... that's a big Niner, MPG.

Shaners · October 18, 2003

My buddy with his 8.1L Avalanche was in the single digits also until he put in a Westers PCM.

CMNTMXR81 · October 18, 2003

Hey, a tank or two ago, I managed a 9.4 mpg!!! Wooohooo!!!

THE BIGPUNN · October 18, 2003

9.9 mpg. i use my gmcard for fuel....i'll break a record for fastest amount saved for my wifes next gm vehicle. probably something that gets 20mpg!!!

BrokenBoots · October 18, 2003

Shanners,

What's he getting now with the W. PCM?

High Mileage · October 18, 2003

I'm doing a lot of mixed driving with my 03 Dually, 8.1. (Washington DC contractor) As far as loads go I am a lmost always empty with the exception of a truck box and ladder rack. Luckily I've never get less than 10mpg unless towing. Since breaking 20k miles I've been experiencing 11 and 12 mpg at fillups. I took a load of 20' lengths of pipe accross the West Virginia mountains and that trip did wonders for the way my transmission operates. Also note that this was the first tank that I ever achieved 12 mpg.

I have only two realist modifications that I wish to perform to this vehicle. 1 is the PCM programing upgrade. 2. is a gear vendors aux transmission. (they have yet to complete a kit for this application)

I expect that 14mpg is within reason along with stronger performance.

Oh, my driving characteristics, mid to 3/4 throttle launches to get up on plane (speed limit) and set the cruise control.(keeps the law out of my pocket)

422 SS · October 18, 2003

Your mileage is normal.I put 58,000 miles on a 2002 2500Hd in 2 years.The trucks was mainly my wifes daily driver and my occasional trailer tower.Average fuel economy was 9.4 mpg.It was a crewcab 4x4 shortbed with 3.73's.

Shaners · October 18, 2003

Shanners,

What's he getting now with the W. PCM?

His first tank with the Westers PCM installed was between 10.5 and 11 MPG. He ran the truck hard with alot of speed limiter runs and smoky burnouts. He also had a weekend camping trip towing his 27' travel trailer. He hasn't been driving the truck much lately, so he hasn't run the 2nd tank through it yet...

tgdiver · October 21, 2003

10 mpg with my 350 TBI. Granted, I am in high gear at 30 mph. whew - motor screams @ 70 mph.

tmf6902 · October 21, 2003

d**n I guess I'm doing pretty good. I average 10.5 in the city, and 11.5 to 12 on the highway.

EDIT!!!!

I forgot to mention, I changed my fuel filter and plugs at 30K and the mileage increased dramatically, so if you having problems with MPG might want to try it?

pecoman · October 22, 2003

2001 Van 8.1, 3:73 auto, 50k miles average 12 mpg

Jim

ssminneapolis · October 22, 2003

2003 silverado ss...17k miles...average about 12.5-14 mpg..depending on driving of course...

jimary · October 22, 2003

I have a 01 3500 4wd dually with the 8.1 ally 78,000 miles I average

11.0 mpg towing or not. I usually tow around 8,000 lbs. on weekends

over 1,000 miles. this is the third 3500 I have had and the best.

performance of the 8.1/ally combo is awesome. I know a lot of people

like the diesel, I drove one before I got the 8.1, but the feel of the 8.1 at full throttle is very satisfying.

ugeesta · October 22, 2003

I'm getting around 11 with my 8.1/Allison.

mhsneon · October 22, 2003

I get 8-10mpg in town with my 8.1/6-spd, 13 on the highway at 80mph with cruise on. I have 4.10's wich doesnt help highway milage. Towing I have gotten 11-12 on flat ground towing 5000lbs at around 60mph. In the mountains towing, let's not get into that one.