MPG and Overdrive Question

[OHBandit]

OK I have a couple issues/questions here. My set-up is in my signature.

My truck is my daily driver and my drive to work is about 10 miles of non highway driving. I am running DP Tuner in 80 econ. Average speed may be around 40 mph. I am consistantly getting 11 mpg and that is calculated (not of the overhead computer). It was quite a bit better than that before I did the 4" lift and 35's. I have had the abs module calibrated for the 35's and the speedo is within 1 mph at 60 mph so I'm confident my odometer is accurate. Is this normal mileage with my set-up?

Also, at normal acceleration my truck doesn't go into overdrive until it reaches around 48 mph. I really don't remember but it seems like when I first got my DP Tuner that in 80 econ it went to overdrive around 40 mph. Obviously with my commute being mostly 40 mph or slower, I'm not getting into overdrive much leading me to beleive that this may be the culpret to my bad "in town" fuel economy.

Thoughts.....

[Big_Stroker]

I was never impressed with the way DP Tuner shifting is at them kinda speeds.

I am getting 18mpg with my current setup.

IMO try some different tunes.

[OHBandit]

Originally Posted by Big_Stroker

I was never impressed with the way DP Tuner shifting is at them kinda speeds.

I am getting 18mpg with my current setup.

IMO try some different tunes.

Yeah I've been considering that but that doesn't explain everything. My mileage has dropped while running the same tuner. The DP was the first thing I did to the truck.

[Mikey's250]

I have the same problem since I put 4" and 35's on mine I get 10-12 everytime I fill up and it sucks. I used to get no less than 15 anytime, 20 on all highway. I run my edge evo on the 80 horse setting most of the time I know I need new tunes but maybe BigStroker is right we both might.

[Big_Stroker]

How is your EGT's and Boost looking?

Your turbo might be dying a slow death and causing your issues.

Could also be a boost leak... Check your up pipes

Also have you been running additive with the ULSD?

[OHBandit]

Originally Posted by Mikey's250

I have the same problem since I put 4" and 35's on mine I get 10-12 everytime I fill up and it sucks. I used to get no less than 15 anytime, 20 on all highway. I run my edge evo on the 80 horse setting most of the time I know I need new tunes but maybe BigStroker is right we both might.

Yep that's me exactly!

[OHBandit]

Originally Posted by Big_Stroker

How is your EGT's and Boost looking?

Your turbo might be dying a slow death and causing your issues.

Could also be a boost leak... Check your up pipes

Also have you been running additive with the ULSD?

EGT's and boost don't look any different than before. I pretty much baby this truck and drive it like an old man 99.9% of the time. I went with the larger comp. housing to eliminate surge while towing which it did.

No I haven't been running any additive but I never did before. Just trying to figure out why I've dropped 3 to 4 mpg and I wouldn't have thought the 35's would have done that.

[DJM]

With My setup I average 14-15 and my speedo and everything is adjusted I also Have a DP and drive in the 80 econ tune. IDK try running an addative for one tank. the bigger tires do make a considerable differance before I had my 37's I was getting around 18-19.

[Big_Stroker]

Also winter fuel will cause a 1-2 mpg drop if you dont run additive with it.

[DJM]

Also winter fuel will cause a 1-2 mpg drop if you dont run additive with it.

Ya forgot about that. That will do it too.