First big load using a gooseneck - fuel mileage problems

[rickhans]

With thanks to others on this forum for their answers, I now have a 16k 20'/5'dove tail trailer with load range G tires to carry the 13,400# man lift I purchased. Having towed with bumper pulls for 35 years, a gooseneck takes some getting used to.

I drove to Houston with the trailer empty (weighs about 2400 pounds - single wheels - ) and got 12 mpg at 70 mph. My milaege has been staying at about 16.5 without towing for some time now at 70 avg, and 15 in the city. At one time I got 17 and 19 mpg. I only have 41k miles and I have read many topics on this forum about fuel milaege.

I loaded the Condor and drove back to Dallas, again running 70 most of the time, once and a while 75, and averaged 9.7 mpg.

I know something must be wrong, and plan to take it in for some other warranty work but need some suggestions. Sometimes my turbo sounds strange. Is there a way for them to test it and see if it is not boosting properly? How can I convince them to check the injection timing? The last dealer I had look at fuel milaege said they don't mess with the timing. My clutch is not slipping, then temperature stays cool, although towing the heavy load stayed right on center - 190 I think it says. What is the temp. requirement for the computer system to go into closed loop, or does the diesel used different technowledgy? I have tightened all clamps, changed all filters and oil at the same time, but saw no change in milaege.

Any ideas?



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98.5 24V QC 4x4 SB 3:54 5sp