Ford V10 mpg

[Ksrdrunner]

I have a 99 F250 with the V10 and about 85000 miles. Pull a load fiver of about 10000 lbs.
When new I averaged 8-9 MPG. The last two years MPG has dropped to 7.5. Even tho the truck ran great I had plugs and fuel filter replace at 80000 miles. No increase in mpg so I converted from 3.73 to 4.10 rear end. No reduction in mpg but it sure pulls better.
Yep I'm still driving about the same speed.
Any ideas on what might cause the reduced mpg.
Thanks
KsRdRunner

[Ksrdrunner]

I have a 99 F250 with the V10 and about 85000 miles. Pull a load fiver of about 10000 lbs.
When new I averaged 8-9 MPG. The last two years MPG has dropped to 7.5. Even tho the truck ran great I had plugs and fuel filter replace at 80000 miles. No increase in mpg so I converted from 3.73 to 4.10 rear end. No reduction in mpg but it sure pulls better.
Yep I'm still driving about the same speed.
Any ideas on what might cause the reduced mpg.
Thanks
KsRdRunner

[Hitchhiker]

Hello Ksrdrunner,

Welcome to iRV2, we're really glad to have you here as a new member and are looking forward to reading your posts about your RVing experiences and adventures. I noticed this was your second post since joining in '03.

You'll find a great bunch of folks on this site who are very knowledgeable of RVing, the rigs we use, and the places we go in them.

Can't be sure what's dragging your mileage down but often times we add more weight to our rigs as we use them over the years. Is it possible that you're running a little heavier now than before? Might drop it on a J-Scale next time you're at a Flying 'J'. I'm sure you've addressed all the basics such as tire pressure, alignment, easy on the go pedal, air filter, etc.

You might want to post this over on the gas section of the The Diesel Stop, there's usually some pretty good discussion going on about the V-10.

As you'll see, they're eager to help and share their knowledge and experiences with others.

Again, welcome to iRV2, we're glad you joined.

[Frankenstien]

May want to consider a new set of O-2 Senors, they have the ability to make a world of difference. Also check the Mass air flow sensor for debri, and dust, a good Carb Cleaner will do the trick to clean the screen and Throttle body.

[VanMan]

I lost about 3-4 mpg almost overnight!! I tried everything short of changing O2 sensors or taking it to an expert!!! I finally found out what it was after talking to a couple of folks. I had BF Goodrich all terrain tires put on - with those BIG DEEP treads!! I really did lose the mileage overnight!! But I can now pull my TT off road if I want to !!