We will soon be leaving with the camper and towing Southern Indiana hills. This is the first trip with our Ex V10. We will be towing 6500#. What MPG should I expect?

 

8. What size tires?

 

What gears does it have and how big are those hills?
I'll guess between 7 and 8 MPG if you are heavy on the pedal and try to maintain your speed on the hills, 8 to 10 if you are trying to get better towing mileage.

 

16" Tires...I recently got 13.5 highway driving conservatively 65mph. No camper of course. Looking forward to towing with it.

 

4 Speed w/ OD. Specific gearing...what am I looking for?

 

Negative.

You have a 4R100 transmission which is a 4 gear trans. Or stated another way, it's a 3 speed with Overdrive transmission.

When Tom asks about your gears, he's asking you about the ring and pinion "gears" in the rear end.

Stewart

 

16" would be the rim size, it's the stock size rim but you can various sized tires mounted on them, the stock tires on our EXs was 265/75R16 which was about 31.5" tall.
13.5 seems to be fairly average for a V-10 highway MPG, how many miles on the EX?
All V-10 EXs had the 4R100 4 speed auto trans with OD, standard factory gearing was 3.73 with an option to get the better towing ratio of 4.30. The driver door jamb should have a sticker that will have a letter/number code under the "axle" heading that will tell you which gears it should have.

 

Yes it is 3.73. What are the implications of this?

 

A deeper gear (numerically higher value) offers more reduction of the engine's rotational output. Since the engine is making a specific amount of power/torque the more reduction you can get from deeper gear ratios the better that power can be applied to the work at hand, towing grunt or better acceleration.
As an example, our EX with the stock 3.73 gears would struggle climbing any hills towing our 9,500lb toyhauler and would have to downshift when towing on even low rolling hills. The towing gas mileage suffered because of this and we were seeing 6 to 7.5 MPG on our towing trips. I later upgraded to deeper 4.88 gears, which keep the engine spinning at higher RPMs at the same speeds, these V-10s make their bast power at slightly higher revs than they see with the 3.73 gears. Now with the new gears it pulled that same trailer over the same route at the same speeds and got 9 MPG. This was due to the better application of that available power due to better gear reduction which allowed for more time spent in OD vs having to downshift.
Currently with my taller 35.28" tires and those 4.88 gears my effective ratio is 4.39 (the ratio is effectively reduced by the larger diameter tires) and it is now towing our 11,000lb travel trailer. It still gets between 8 and 9.25 MPG towing and can stay in OD on most Eastern mountain Interstate Highway grades. My EX also has Banks headers and custom tunes from 5Star Tuning which help to make this performance possible.

 

Fat fingered double post. Oops!

 

I love Tom's posts. Always so clear and informative.

Anyway, is your Ex a 4X4 or a rear wheel drive? Not sure how much MPG difference (if any) that would make, but most of us usually assume someone has a 4x4 when it isn't mentioned.

Are you from Indiana? I'm up in the Kokomo area, and we plan to do some camping with the Ex in southern Indiana this summer.

 

Northern Indiana Marshall County. . . We will be headed down to Shades, Lincoln, & Obannon Woods SP. There are some decent hills down there for Indiana.