Just some info for those that are interested. Took road trip over the weekend and thought I would post up the MPG info.

2000 V10 4x4 bone stock everything, with 4.30 limited slip 198,000 miles

Drove 420 miles in rolling hills (no flat stretches) with cruise on 75 MPH (gps verified) and got 12.9 MPG. Tires had 60 psi all four corners. Just me in the X but she was pretty full on stuff that I needed to detail the boat and perform some repairs.

I also did a 60 mile stretch with cruise on 62 MPH and only got 13.8 MPG. At the lower speed I would have expected a bigger difference in MPG................

 

That's not too bad with our gassers, especially over the hills. I usually get 12.5 mpg on highway trips and 10.5 around town, and that's hand calculated not the lie-o-meter. I have the standard 3.73 gears.

 

Not bad, I wouldn't mess with that truck, just maintain it.

 

I could get 14 at 65 with the 4.30’s. When it had 3.73’s I could do 15. Anything over 65 the mileage drops!

 

Drove to Mammoth last winter fully loaded and got 14-15 doing 65, fairly flat most of the way.
Around town usually get 10-12.
Pulling a 7.5K TH 8.5 flat and 7.5 hills.

 

Best I ever got from my V-10 F-350 was just over 10MPG, but it had a big lift and 37' mud tires. Towing my massive boat it dropped to about half, or less.

 

I get a bit under 10 in town, 12-13 on the road. A couple of years ago I filled up in South Alabama and drove on flat open roads where I had to keep my speed down to about 60 and got 15! Don't know what was in that fuel, but the next fillup it returned to "normal".

Towing the boat on interstate at 70 I get about 11. Run over 80 and the mileage is under 10, but that motor wants to run there. The normal power band for the V10 is 2,200 - 2,400. This one like 2,600 - 2,800 and is really strong over 80.

 

I average 12.5 to 13.5 on all 3 of my v10s.

I have a theroy that people running 195 degree tstats get a tad lower mileage due to the clutch fan being set up for a 185 degree tstat.

 

I am getting a best of 9.6 mpg. V10, all stock, 163000 miles. The only thing I noticed is when I log the O2 sensors on one of the android apps, one of them is flat at ~0.8v in closed loop. I am wondering if that is contributing to my bad mpg.

Any thoughts?

Thanks

 

. . . no matter the RPM? TIf "yes" then yes that could be related.

 

That is correct. No matter the rpm. The other O2 is cycling normally, but this one stays at 0.8v.

I'll add another item to the maintenance list

Thanks

 

Just did the exact same trip and got 13.7 MPG. Same type of weather, same load, same roads............. The only difference is I changed out both diffs and transfer case with synthetic.

So............ Synthetic fluids in both differentials and transfer case netted almost 1 MPG Not to shabby IMHO...............

 

I thought the OEM diff fluid was synthetic.

 

Back when my '05 V-10 EX was all stock with 3.73s and 265/75R16s it would see 14 MPG on my daily driving mix of 50/50 town/highway driving. In that configuration it had a best ever tank at 15.5 MPG while vacationing in ME with 6 adults onboard running along the coast highway between little towns in very warm weather.

Current configuration at 125K miles is 4" lift, 35" tires, 4.88 gears (effective 4.39 ratio), Banks headers, 3030XL muffler and 5Star 89 Octane Performance tune.
These days it sees very little unloaded use as it serves as our dedicated tow rig for the nearly 12K TT, towing that it gets from 7 to 9.5 MPG depending on the terrain, traffic and our time schedule. Last Summer on a rare unloaded trip home from Columbus OH to the Philly burbs (about 470 miles) I set the cruise at 65 MPH for the entire highway trip and was surprised to see 14.5 MPG.
When I had the 4.88 gears and 32" tires I drove it unloaded to Savannah GA (700 miles, all highway) at 65 MPH and got 12.5 MPG, return trip was towing a Geo Metro on a car dolly at the same speed and got the same mileage.

 

The only time I really checked MPG on my 2005 V10 was on a trip to Michigan towing a 22’ enclosed trailer with a car inside.

We set the cruise for longer stretches and around 70MPH it was single digits...mid 9MPG. At 65 or slightly below...12MPG. Slower speeds with the trailer are probably a good idea anyhow.

I will say that I’ve noticed cruising about 2000-2500 RPM dramatically changes the MPG.