How to improve gas mileage E350 4x4 - Page 2

**rionapo** · 05-07-2021, 07:23 AM

Does anyone know how or why SMB wants 60/80 (or whatever it is) for tire pressure? I’ve assumed it’s the price of a 9,000 lb. vehicle.

carringb · 05-07-2021, 10:03 AM

Those pressures are simply the minimums to achieve the FAWR and RAWR with the specified tire size. Tire ratings are at max speed rating, so for low speed travel it’s ok to lower them. Just air back up before getting on the highway. Running wider tires allows lower pressure. You just have to reference the tire manufacturers load chart.

boywonder · 05-07-2021, 02:12 PM

If you own a 2008+ the TPMS light will be on for pressures much lower than 70psi front and 80psi rear.

..and if you live in CA sometimes that can be a PITA when smogging, although these days they don't seem to care much.

Lilnuts2 · 05-07-2021, 03:34 PM

In order to get better mileage from your van:

Step 1 Tow it to the top of a hill.
Step 2 Reset your mileage meter.
Step 3 Coast down until you come to a complete stop.
Step 4 Record fuel consumption & distance.
Step 5 Compute info.
Step 6 Go inside your van with a beer in hand, and tell her you love her.

Kibo · 05-07-2021, 08:01 PM

Quote:

Originally Posted by boywonder

If you own a 2008+ the TPMS light will be on for pressures much lower than 70psi front and 80psi rear.

This is pretty easily fixed using Forscan. I have mine set for 50/70 F/R based on loaded axle weights and the pressure/load chart (285/70R17 BFG K02s, V10 EB Quigley). The 50 up front definitely took away some handling responsiveness on pavement (a bit more sway), but the tradeoff is a smoother ride. I was originally thinking I would lower the rear pressure a bit more, but it doesn't seem harsh on roads and we drop the pressure anyhow when driving off road. Caveat, we have Alcan progressive leaf springs in the rear.

**rionapo** · 05-07-2021, 10:02 PM

Quote:

Originally Posted by carringb

Those pressures are simply the minimums to achieve the FAWR and RAWR with the specified tire size. Tire ratings are at max speed rating, so for low speed travel it’s ok to lower them. Just air back up before getting on the highway. Running wider tires allows lower pressure. You just have to reference the tire manufacturers load chart.

Thanks. I figured it was a SMBW thing.

**Gooseberry** · 05-08-2021, 10:40 PM

I’m at 65 on all four with same weight on each axel and get 16 mpg on a 2000 7.3 with 33 inch tires

Pete · 05-13-2021, 09:58 AM

Interesting that the OP never said what motor. Sure seems to be a critical part of the equation, in spite of the jokes.

bolty · 05-13-2021, 10:28 AM

Last I checked my E350 got maybe 10 or so on the highway, down as low as 6 when doing a lot of low range. I weigh about 10,400 lbs driving down the road with medium aggressive 285 tires.

Vanzila · 05-13-2021, 10:36 AM

Quote:

Originally Posted by Magnus

I have a 2014 E350 4x4, and its getting about 8MPG in the city, seem normal? Any recommendations on how to MPG is appreciated!

Yes Normal. My 96 5.8L Gets about 12 empty on flat ground. When it was new it got about 18. When Loaded or Towing it will get under 10mpg as low as 8 in hill country.