I have a 01 250 v10 373 gears was wondering what speed or rpm you guys find for the best fuel mileage? Thanks for the help

 

I usually don't let mine get above 2k when taking off from a redlight. dont go faster than 60 mph thats when mileage starts going down. I get 13 to 14 depending on how I drive it.

 

Scroll down to a thread titled "Finally opened her up" on page 3. A poster there says at 70 mph on the interstate he was getting 14-15 mpg but the same trip at 90 mph gave him 18-19 mpg. He, too, was driving a 2001 model v10. He did not specify what differential gear ratio he had. Another poster claimed to also get better mileage at higher speeds.

 

best i've seen is 13ish at 65/70mph with my 3:73s.

 

Don't believe everything you read on the internet. There is no possible way ANY F250 or Excursion with a V10 is getting 19 mpg at 90 mph. There are some instances where over-geared vehicles benefit from a little extra RPM's to get into the heart of the power range, but the wind resistance at 90 MPH in a full-sized truck is horrendous and will certainly offset whatever power gains the engine is making. All internet forums are full of outlandish claims but like the old saying goes, " Don't believe anything you read and only half of what you see"

 

agreed never in a million years would it get 19 mpg at 90 like I said 60 mph and above is when fuel mileage drops alot.

 

My truck seems to like 55mph pretty well as far as mpg is concerned.

 

At 90 miles an hour my truck would't get 19 miles per gallon, it would get 19 gallons per mile!

 

99, F350, DRW, ext cab, V10 (of course), 349,+++ on the odometer, 13 mpg when driving 60_65. Drops to 11.5-12 mpg when driving 75. Like others have said, it is rare to get any better than this. Only mods are: K&N air filter and after market Dynaflow mufler.

 

My old 2000 scsb 4x4 with 3.73s would get a hair under 16 mpg on the 2 lanes at 58-60 mph. Bump it up to 70 out on the interstate and I would see about 12.5 mpg. These trucks have the aerodynamics of a brick, so high speeds will always negatively affect economy.

I honestly feel a 4.10 geared truck on stock tires would get best possible mpg of any configuration running around 60 mph. Sweet spot for wind resistance versus heart of power/torque curve for cruising unladen.

 

Driving back on I80 from Indiana to California. 80-95MPH about 11.5MPG turning around 3Kish.

Besty milage I got was on the way there doing 87MPH. Got almost 15MPG. Of course I had a big rig right in front of me the whole way breaking wind for me.

99 F250SD SC 4x4 V10 4.30LS 285/75/15 BFGs

 

45mph gets me 16mpg if you can stand to go that slow lol

 

thats what im talking about if u got it use lol!!!

 

With 260000miles on it I'm real happy with how it runs. I don't generally push my vehicals that hard but I lost two days on my trip when the spare tire fell out from under the bed so I had to make it back before Monday. Ran like a champ but I sure hate it when it would down shift at that speed but even turning 4500RPM I didn't hear anything that sounded bad about how it was running.
I have got a little noise in the morning when she's cold. Sounds like piston slap but after a few seconds quiets right down. I'm sure I'll get over 300K before it's done. Then it's a PI motor with porting and headers. Can't do much because of Kalifornia rules. But the rule say that if you change the motor you must keep it the same or move forward. A 2000 with PI intake, a little head work to help it breath, and still with an EGR would keep me legal and give me a little more HP. I'd probably have to buy a tune from mike to pass smog. LOL So that would be a performance tune, a tow tune, and a california detune.

 

Whats a PI motor?