Eskimo
Full Member
OK.. so we all know slowing down helps when towing, but damn, I was surprised it would (with another style change) help by 20+%! (MPG FAIL is my license plate )
Truck is my '04 2500, 3.73, modded stock airbox, dyno tune, 93 octane, and a cat-back exhaust. Front is leveled, and I'm riding on 275-55/20 LRR tires. (General Grabber HTS). Trailer is a 7x16 flat-nose, extra-height Car-Mate enclosed with a high-profile A/C on the roof (OAH: 9'3"), only weighing around 5k loaded, but has bad aerodynamics.
My previous style (That I've been using for close to 2 years with the same setup) was this.. Cruise control set at 70-75. When approaching a hill, I'd lay into the throttle so that the Inst. econ read 6-7 MPG, which is the most throttle it'll accept in OD without downshifting, and disengage the cruise. If the speed dropped by more than 2-3 mph, I'd downshift to 3rd, and try to keep the inst. econ at 4 MPG or above. In PA and surrounding areas, there are lots of short hills followed by more short hills, so there's a LOT of uphill, downhill, uphill combinations. Going downhill towards another uphill, I'd hold the throttle at 6-7 MPG to make a run at the next hill, letting the speed run up to a max of 75-80, so hopefully keep it over 70 by the top of the next hill.
That style gave me a very consistent 8.2-8.6 MPG as average, and on a trip that the GPS says would take 3:30 (hr:min), it took 3:30.
Lately, I've been trying this.. Cruise is set at 65-70. When approaching a hill, I still roll into the throttle to the 6-7 MPG reading, but now, I let the hill drag the speed down, trying my best not to let it downshift. If the speed drops to under 60 (usually right around 56-57), I will downshift to 3rd, but keep the inst. econ at no less than 5MPG, usually shooting for 6 or above. Going downhill for another uphill, I roll into the throttle to the 7-8 MPG reading but won't let the speed go over 75. Basically, I'm driving more like the semi trucks.
This style has netted me no less than 10.2, often 10.5, and as high as 10.8 MPG. Trips that are said to take 3:30 take 3:45.
I'm absolutely blown away that trading off a 7% time increase nets me over 20% in economy.
Picture of truck & trailer for reference:
https://goo.gl/photos/WtmvtwYtTULb81Wx5
Truck is my '04 2500, 3.73, modded stock airbox, dyno tune, 93 octane, and a cat-back exhaust. Front is leveled, and I'm riding on 275-55/20 LRR tires. (General Grabber HTS). Trailer is a 7x16 flat-nose, extra-height Car-Mate enclosed with a high-profile A/C on the roof (OAH: 9'3"), only weighing around 5k loaded, but has bad aerodynamics.
My previous style (That I've been using for close to 2 years with the same setup) was this.. Cruise control set at 70-75. When approaching a hill, I'd lay into the throttle so that the Inst. econ read 6-7 MPG, which is the most throttle it'll accept in OD without downshifting, and disengage the cruise. If the speed dropped by more than 2-3 mph, I'd downshift to 3rd, and try to keep the inst. econ at 4 MPG or above. In PA and surrounding areas, there are lots of short hills followed by more short hills, so there's a LOT of uphill, downhill, uphill combinations. Going downhill towards another uphill, I'd hold the throttle at 6-7 MPG to make a run at the next hill, letting the speed run up to a max of 75-80, so hopefully keep it over 70 by the top of the next hill.
That style gave me a very consistent 8.2-8.6 MPG as average, and on a trip that the GPS says would take 3:30 (hr:min), it took 3:30.
Lately, I've been trying this.. Cruise is set at 65-70. When approaching a hill, I still roll into the throttle to the 6-7 MPG reading, but now, I let the hill drag the speed down, trying my best not to let it downshift. If the speed drops to under 60 (usually right around 56-57), I will downshift to 3rd, but keep the inst. econ at no less than 5MPG, usually shooting for 6 or above. Going downhill for another uphill, I roll into the throttle to the 7-8 MPG reading but won't let the speed go over 75. Basically, I'm driving more like the semi trucks.
This style has netted me no less than 10.2, often 10.5, and as high as 10.8 MPG. Trips that are said to take 3:30 take 3:45.
I'm absolutely blown away that trading off a 7% time increase nets me over 20% in economy.
Picture of truck & trailer for reference:
https://goo.gl/photos/WtmvtwYtTULb81Wx5