Increased Towing Range By 25%!

I wanted to share my towing experiences from this past weekend

I've got a '10 4x4 Sport w/ TRD S/C and 6-spd. I hauled a 6'4"x12' utility trailer and an ATV about 300mi from northern VA to Beckley, WV. There's not much thats flat on this route. Total weight of ATV+trailer is about 1800lbs + <200lbs of gear and tools, no passenger. Probably another 300lbs in truck stuff; front and rear steel bumpers, skid plates all over, etc.

Going down I got 9.7mpg holding 75mph most of the way, I let the cruise control do its thing, downshifted to 5th and sometimes 4th for the hills. When the needle reached a half tank I was at 95 miles.

My trip back was in the late evening and little traffic. I have a PLX OBD scanner. I kept engine loads below 70% and let that dictate my gear selection and speed. I was in 5th for half the trip, speeds would drop to 50mph in 3rd on some of the hills.

I also followed a semi whenever I could. Engine loads would drop by 10-15% when the semi was leading.

The end result is I got 125mi out of a half tank. Engine oil temps stayed much cooler. Its definitely more work but it made the drive more interesting and it only added about 10min to my GPS' ETA.

Haha I'm sure that for a lot of you not hammering to 125% load and 6psi in 5th to get up a hill is common sense but it was a new thing for me. I just like to hear it whine

I'm making a drive to Michigan tonight, no trailer, just me, the fiance, and the dog. I'm going to try the same thing and see what I get.

 

When I pull a trailer, the shifter stays in '4' the whole time. It doesn't hunt for gears and still get 11 mpg either way. Transmission stays cool as well since it doesn't shift hardly.

 

^SManZ has the 6-speed manual transmission. 5th isn't the top gear. All SManZ has shown is driving at slower engine rpm improves fuel economy. It is nonetheless good information for other newbie 6-speed owners who might think cruise control gives best milage.

 

Not exactly...

My findings are that reduced engine load at higher rpm nets better mileage. Lower rpms would dictate just keeping it in 6th as much as possible and that got me 9.7mpg.

 

X2

If you think about it, when staying in 6th gear and you start to load the motor but don't down shift, the motor pulls in more air and fuel to attempt to maintain that speed. It'll get to the point where it is pumping as much fuel as the fuel pump will allow it and pull as much as to stay correct and yet may still slow down. Dropping down a gear and maintaining a steady rpm and fuel is much better. Not only for fuel economy but it also puts less load on the transmission and rear, which keeps those temps down and extends the life.

 

An engine is most efficient working in its powerband. In high gear it's lugging with a load so gas is just going out the tailpipe, in too low a gear it's reving past where it works, which doesn't produce useful work so again gas out the tailpipe. Quick and simple, if you can't give it any more pedal without exploding the engine, you're too low. If you give it more pedal and it can't accelerate, you're too high.

And drafting behind a semi throws all that out the window. They carry a low pressure area behind them, get close enough and you'll get amazing mpg, it will pull you along and the engine will barely have to work.

I know many of my mountain trips I'm really wanting a 3 1/2 gear My last trip I ran about 13mpg with the 2.7 pulling a couple'ish thousand pounds. I was in 3rd and at a reduced speed most of the way up, 4th just didn't cut it.

 

Just this past weekend, I had a VERY similar experience - right down to the truck, trailer and area of the country!

I purchased a new enclosed 7x14 trailer with an empty weight of 2060lbs. My truck is a '11 4x4 TRD Offroad with towing package and 6-spd but no S/C. I towed from Beckley, WV to Liberty Township, OH. My buddy had towed the trailer from Charlottesville to Beckley. From Beckley to Washington Courthouse, OH I saw 9.73 mpg. This area is mostly hills and I spent a fair amount of time shifting back and forth between gears 6/5/4 while maintaining 65ish or so. From Washington Courthouse to home I got around 11.2 mpg. The improvement came from spending more time in 5th gear, drafting semis whenever I could and going a little slower (around 60-62 mph). I too was surprised at the improved mpg from 5th gear.