1997 GMC 6.5td MPG

[wayt7017]

Hello everyone! new to this site and so far pretty good site. i was wondering if anyone could help me about MPG. I have 1997 GMC K1500 6.5td. no mods but home made air filter assembly. i have had the truck a little over a year and i am getting an average of 12 MPG. Some of my friends have the same engine and are getting anywhere between 15-21MPG. the fuel injector pump has been replaced and truthfully it seems to be worse now than when the pump tested bad. any info would really help and i look forward to talking to everyone! Thanks!!:)

[torque454]

How many miles? Have the injectors been replaced? Any smoke, especially excessive? Mine only makes 12-13 in town, but on the highway that jumps to22. And I know mine needs injectors.

[wayt7017]

just turned 83500 miles. the best mpg i got was when i drove from ohio to tennessee and that was 15.86 MPG. no smoke while running or even when i get on it the only time ther is smoke is when i first start it and it is very little white smoke.

[torque454]

I think you should check for boost. They say low or no boost causes smoke but mine doesnt have any boost right now and the smoke is hard to see. then again my milages are alot better than yours are too. So it doesnt make a whole lot of sense to me, especially with such low milage.

[deerefanatic]

Yah, I average 17 just rammin' around the back roads and such, 20-21 out on the freeways toolin' 75mph..............

[Chevylover]

MPG depends on :

tire size
lifted or not
driving behaviour
traffic situation
town, freeway/interstate
short or long runs (above 15 after cold start)
gear ratio
towing or not
O/D or not
other equippment (bullbar, moonvisor, camper top, flat cover or open)


I got an average between 15 and 20 mpg depending on different situations mentioned above.


Cu,
Sven

[Oldsmoke]

Mathematical error is possible when converting to miles/American gallon but I'm pretty sure my truck would average in the 16 to 18 mpg. range unloaded and low 20's on a trip.