Poor performance out of my 6.5

[Goob G.]

I have a 1994 crew cab truck with a new 6.5 engine. I pull a 26 foot enclosed racecar trailer with my truck. My mileage avgs.6-7mpg. towing and has very poor performance on even small grades! I have installed a fsd heatsync,4 inch exhaust,new injection pump,new turbo,new lift pump,ssd-707induction kit and a hypertech chip (part#124983) but had to remove it because of heating problems when installed!

Thanks for any suggestions,

Goob G.

[Scrufdog]

how heavy is the trailer? I go from 18mpg to 11mpg when towing an 8000lb 16ft trailer. Still pulls up most hills no prob though.

[Goob G.]

My pickup and trailer together weigh around 21,000 lbs.

[Scrufdog]

well, I roll at 15,000 pounds to get 10-11mpg. So 6-7 might be as bad as you think. What do you get when not towing? At any point are you spittin black smoke? Got gauges?

[Goob G.]

I get 12-13 mpg. when not towing and the truck does puff black smoke when pulling hills or hard acceleration! I have no gauges!

[rypie32]

I have a 1994 crew cab truck with a new 6.5 engine. I pull a 26 foot enclosed racecar trailer with my truck. My mileage avgs.6-7mpg. towing and has very poor performance on even small grades! I have installed a fsd heatsync,4 inch exhaust,new injection pump,new turbo,new lift pump,ssd-707induction kit and a hypertech chip (part#124983) but had to remove it because of heating problems when installed!

Thanks for any suggestions,

Goob G.


Do you still have the vacuum controlled wastgaste? If it is smoking alot, especially just driving, I would bet the wastegate is acting up. My 96 1/2 ton it was doing that a couple years ago, turned out the waste gate was causing the poor performance, but the the vacuum pump was the culprit. Does your cruise contol work? Not sure on a '94 but, that was the tell tale sign on mine, that the vac. pump was out.