ideas from the group.
Truck= 1991 C2500 Silverado. Trailer package, 5.7 350 tbi with tbi riser plate and 4l80e trans.
120 Ltr tank.
Pulling 5200lbs travel trailer and about 1000# in the box of gear.
I only pull in drive, I dont tow in od.
Engine is strong, transmission has cooler and shift kit and is prestine when serviced by transmission shop.
My problem is this, decent gas millage when not pulling, about 6-700km highway.
But pulling at a steady 100-105km/h my gas millage is worse than bad.
I can get about 180-200km on the top 1/4 of my tank from full to 3/4 mark when not pulling.
But I used 3/4 of my tank when pulling 176km to our campsite. Ouch!!!!
Now my other issue is my trany isn't slipping but its boiling trany fluid out the breather, everything I tow. Advise my trany guy said to try a bigger cooler for the first attempt to address the fluid spew.
I just put a tack on to make absolute sure my trany isn't slipping.
What are you thoughts from the group?