Just got back from vacation in Arkansas. Did a wee bit of fly fishing on the White River.
I pulled my 7K lbs. 5th wheel.
Cruised in 6th most of the time. 11. 5-12mpg going to Arkansas.
Hills on US 65 are marked 7% grades of 1+ miles. !No problem! 5th gear, 2200ishrpm 57mph and set the cruise. (6 speed transmission. ) EGTs never passed 750 degrees.
Coming back was interesting. 20 to 30mph headwinds. Set the cruise at 67mph in 6th gear at just under 2000 rpms and averaged 800 degree EGTs on flat land. EGT hit 900 degree several times. (OK, I'm a wuss! 900 degrees post turbo is where I draw the line. )
I thought that the boost gauge was broken for a while. It ran at 18lbs for a long time. Coming back, I averaged just a wee bit under 10mpg. (I could have slowed down, but I didn't want to back the rig into a spot after dark. )
Interesting fact.
If your running in 5th at about 2400 - 2500 rpm up a steep (over 7% in this case) hill, there's a good change you can burn up a stock truck. I eased off the go pedal at 905EGT and climbining.
I was trying to keep up with the only RV to pass me the entire trip. It was a Dodge CTD 24V 1ton, hauling a Hitch Hiker 5th wheel that must have weighed close to 12,000lbs. When he went by, I could hear his turbo in my truck! I don't know what he had in there, but I gotta get me some!
I pulled my 7K lbs. 5th wheel.
Cruised in 6th most of the time. 11. 5-12mpg going to Arkansas.
Hills on US 65 are marked 7% grades of 1+ miles. !No problem! 5th gear, 2200ishrpm 57mph and set the cruise. (6 speed transmission. ) EGTs never passed 750 degrees.

Coming back was interesting. 20 to 30mph headwinds. Set the cruise at 67mph in 6th gear at just under 2000 rpms and averaged 800 degree EGTs on flat land. EGT hit 900 degree several times. (OK, I'm a wuss! 900 degrees post turbo is where I draw the line. )
I thought that the boost gauge was broken for a while. It ran at 18lbs for a long time. Coming back, I averaged just a wee bit under 10mpg. (I could have slowed down, but I didn't want to back the rig into a spot after dark. )
Interesting fact.
If your running in 5th at about 2400 - 2500 rpm up a steep (over 7% in this case) hill, there's a good change you can burn up a stock truck. I eased off the go pedal at 905EGT and climbining.
I was trying to keep up with the only RV to pass me the entire trip. It was a Dodge CTD 24V 1ton, hauling a Hitch Hiker 5th wheel that must have weighed close to 12,000lbs. When he went by, I could hear his turbo in my truck! I don't know what he had in there, but I gotta get me some!
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