Second long trip under tow !

[M123KT-450]

Ok up date guys i ran the same trip this weekend as last weekend only difference is i ran in 4th gear the whole trip, towing a smaller single axle trailer towing 2 ATV's instead of 3 units on the tandum axle car trailer towing in 3rd. . .truck burned the same amount of fuel round trip 3/4 of a tank so the fuel milage from 3rd loaded heavy and running 4th loaded a bit lkighter had no difference on fuel milage. but instead of just running just under 200*F water temp it ran 210*F the whole trip. so single axle trailer n 2 ATVs was about 40% lighter. . .So why did it burn the same amount of fuel ? why did it run a hotter water temp ?

I was hopping to see it run cooler or get better milage but neither happened it ran a little hotter in 4th gear towing lighter then 3rd towing heavier, It also towing the lighter load in 4th gear burnt the same amount of fuel as running the heavier load in 3rd gear. . .

Trip 1:
3 ATVs tandum axle trailer, 3rd gear running 65mph@3,000rpm water temp 197*F 3/4ths tank of fuel 275miles.

Trip2;
2 ATVs single axle trailer, towing in 4th gear running 70mph@2,400Rpm water temp 210*F 3/4ths tank of fuel 275miles.

please do explain i feel like i am going Crazy here as the fuel milage was the same and the water temp ran 13*F hotter towing in 4th gear with less load. . .is there some thing wrong with this truck ?

Mikey

 

[M123KT-450]

Yes there is somthing wrong with it. . .we can't seem to figure it out. . .Nothing a 400SBC 427TBC or 454 BBC wouldn't solve. . .

Mikey

 

[Joey D]

Yes there is somthing wrong with it. . .we can't seem to figure it out. . .Nothing a 400SBC 427TBC or 454 BBC wouldn't solve. . .

Mikey

Those are all good motors and will most definatly out tow the 6.5, milage will be lower.
One thing you should be doing is checking milage by filling up after the trip to see how many gallons it burns vs just looking at the guage. You could be off a few gallons either way.
Not sure why you see 210 temp towing such a small trailer that can't weigh much. I have seen 210 before on my truck but towing over 10,000 lbs in some nice 85 degree heat through VT.
Now 210 is not bad for the engine, it will run there with no issues. Guage could be off who knows. I would consider cleaning the radiator by removing it and cleaning all the crap that builds up.

 

[M123KT-450]

there just nubers i don't really care what the numbers are. . . the truck simply plan as day ran hotter towing less weight in 4th gear. . .

Mikey

 

[JiFaire]

If the trans was locked up, and you weren't lugging things, then it shouldn't have. Not on the level, at any rate. If it was 'hunting' between lock and unlock, then yeah.

You were also going faster... every one of these rigs has a sweet spot (speed, rpm) that it tows best at. Mine is about 63 mph (locked), towing far more weight than you... if I get up over 70, I have issues - fuel consumption goes up, heat goes up, EGT goes up. If I get too slow, or driving into a wind, I'm better off at about 55-58 mph in third (locked).

You need to drive by the gauges for a while to find yours.

 

[M123KT-450]

The truck seemed happiest in third Locked at 65-67mph running 2900-3000Rpm.

Mikey

 

[M123KT-450]

it ran cooler in third gear. it had a lot more pulling power in third gear. i think for me third gear is the way to go.

Mikey