js2500hd wrote:
Well as it turns out the dealer was full of @##$ on the trailer weight,the gvwr is 8000. I had the trailer loaded to 7800lbs and the 6.0L gas engine imo sucks pulling that kind of weight.
If you like going 40mph up a grade with the engine screaming the entire time, thats fine but not for me.I think it's like driving a 16d framing nail with a tack hammer. The tack hammer will eventually beat that 16d in but it's just not the right tool for the job.
I traded in that gas motor for a 2004 LLY Duramax and the difference is astonishing. The diesel tugs that 7800lbs up grades at 65mph without breaking a sweat. Another big + is MPG that 6.0L with 4.10 gears thought gas was free,10-12mpg empty at 75 , 5-7mpg pulling the bigger trailer at about 55 average. The diesel got 17.7empty at 75mph and 11mpg tugging the trailer at 65mph.
So there you have it,having tried pulling a 7800lb trailer with a 6.0L gas engine I would NEVER EVER recommend it to someone else. But if you are a person that likes crawling up a hill with your foot mashed on the floor and your truck screaming then use the 6.0L gas engine.
Careful....all the gas engine leg humpers here will tell you how the engines are "made" to run at those rpms and how great it is. Problem is, no matter how high you wind up a gasser, you still only get 400ft lbs, give or take, regardless of who makes it, what year it is and what gearing is in the rear end.
Similar experiences about 1000x since my company work trucks have always been gassers and have to tow with them. But the best comparison was, took a brand new, "best truck on earth" 6.2 F250 up to AK with1000-1500lbs in the bed and a 3000?lb single axle enclosed v nose trailer. Averaged 8.5mpg and it was only that good because I was going slow over the frost heaves and 3rd or second gear up every hill.
Same trip 2 months later with my 07 Cummins grossing about 18,000lbs with twice the frontal area with the camper on and a 6klb at least trailer behind it, made a good 3mpg better and only downshift out of 6th if the curves were too tight or the bumps too big to maintain highway speed.