285's and fuel mileage

[Hammer Down]

What kind of mileage are you guys getting when running 285's for tires. I checked mine the other day it was 13.9 running 80mph with juice, without out juice it got worse. That seems pretty poor to me. What do you guys think?

[NWDmax]

On a recent 200 mile round trip got 17.5 mpg running 65.Two weeks ago did a 300 miler at 75mph and got 17.25.Hot juice on kill both times.Kind of want to try it at a different level but I'm addicted to power!Have the BFG's 285's all terrain tires.Just turned over on 17k miles and run a mix of FPPF total power and cetane boost in every tank.
Blake smile.gif

[moto x]

I run 285 B.F. Goodrich A-T T/A's and I have never got less than 16.5 mpg around town even when it has been cold and the truck has been ideling fer qiute a while. On the freeway running 75 - 80 mph I have been getting ~ 19.5 mpg, around 65 mph I get a little over 20 mpg.
The best to date has been a little over 22mpg.
Every thing is all stock except for the wheels and tires, I have about 5600 miles on it so far.

Good Luck

[Hammer Down]

I don't know what the deal is with mine, but I just can't seem to get any mileage out of her. I have about 22k on it right now. Any suggestions on what could be wrong?

[orange2]

From the looks of all the electronic stuff, your alternator is pulling very hard. :D Check your air pressures, do you jump on it alot? I do. E is empty, f is full, whats in the middle don't really matter to me.

[Oongawah]

Orange is right, tire pressure big time. Is 80 what the speed-o says, or what you are really doing? Your odometer is not accurate with those tires so make sure you consider the 15% or so difference. First but not least, ask JK about a bolt on exhaust system. I wouldn't run hot juice without it. Now I just need the salsa!

[TraceF]

I went to Tampa and back yesterday (from Daytona) and I took my GPS along for the second time.

The 285's I have are just a little shy of 8% farther around than the truck "thinks" they are. When the speedo says 70- the GPS will bobble around 75.6 mph.

This means for every 100 miles on the odo, you actually go 108.

I ran on cruise at 70 (75.6) as much as I could and those of you that are familiar with I-4 it's pretty flat from one end to the other.

I got 19.2 average running on Juice 90, level 4. The boost stayed around 3-4 psi and the egt's at about 625-650. It was 78 degrees yesterday in Central FL.

This seems to be the sweet spot, I have noticed if I run the cruise on about 74 (80) the fuel economy drops off almost 2 mpg.

[ZFMax]

I removed my 285's and put on some 265's. Correction factor with the 285's was 7.1%, it's 3.2% with the 265's. Verified on 100 mile freeway jaunts and with GPS.

Mileage went up about 1mpg with the 265's.

The 285's were Dunlop Rover AT's with about 25K on them. Looked like they would've gone another 5-10K. Not good in my book. The fronts want to wear out the edges, the rears want to wear out the centers. Jacked with tire pressures until I was blue in the face and couldn't change that pattern.

The 265's are BFG Commercial T/A load range E's. Reasonably priced tire, and so far, they're wearing like iron, and wearing evenly.

So by switching to the 265's, I got a quieter ride, better handling, better fuel mileage, and better wear, from a lower cost tire. Plus they work on the stock PY0's. No, they don't look quite as good, but the cost of those looks isn't worth it IMO.

[TraceF]

ZFMax- You don't say, but it sounds like you were running them on stock wheels. Mine are 8" wide and seem to wear OK.

[gardnerteam]

285 Toyo on 8" Welds at 65 lbs - wear evenly, but won't last 20,000 miles. 8% correction. Around town average 15 mpg - open road 70 mph or less is 18 to 18.5 mpg. Towing with a vehicle and trailer gross of 25,000 is 10.5 to 11 at 60 mph max. Vehicle is stock except for Amsoil air filter. BUT, it is VERY heavy in unloaded configuration at 9200 lbs without fat old driver - 15,000 Warn, HD plate front winch bumper with solid grill guard, 60 gal tank, shell, 1/2 plate rear bumper. 285 gets no better mileage than the 265's I've run on it or the 295's I ran for 1,000 miles. I get better mgp running my winter studded 235's load range E inflated to 85 lbs. For 20 years I have found I have gotten better tire mileage and better fuel mileage using load range E at 85 lbs than a load range D at 65 (max). Probably will put a 305 E nitto on next unless I can find a 285 E.

[ZFMax]

No, I had the 285 Dunlops on 8" wide PCW wheels. I put the replacement BFG 265's on the original PY0's, though.

[All-tuned-up]

Hammer Down,

I wonder if you're mileage is down because of your tread design grabbing a ton of air? I know those tires are mud terrain and IMHO can throw that off a bit, I don't know about the amount your showing but might be something to consider along with your tire size/speed/mileage adjustments. Try some different speeds, two miles an hour apart. Find the G-Spot :eek:

[mtomac]

Since Thanksgiving weekend when I got the 285 BFG AT mounted on the stock rims I've gotten 15-17 mpg with winter fuel. With the stock tires in Oct & Nov on winter fuel when temps were a little warmer I was getting 16-18. I don't know if the tires or the temps are leading to slightly lower fuel economy. I've had the radiator blocked since Jan to help keep coolant temps up.

[Hammer Down]

I have figured with the gps that I roughly loss 10 miles on every 100 I put on because of the tire change. I figuered this into the mileage when I am checking for mpg. I have also figured that when I run 75 on the speedo I am actually running about 80. Whith this all taken into consideration I still can't figure out why my mileage is so bad.

[KenR]

I'm not thrilled with my mileage either. On the highway with the speedo reading 70, I'm getting about 15 on winter fuel. Drop a 8.5 x 20 enclosed trailer on the hitch, empty, same speed and got 7mpg. 46k miles by the way. Maybe I'm being to critical. Do the boxes (Juice, etc.) improve mileage? I know, I'll do a search...

[ 02-27-2003: Message edited by: KenR ]</p>

[Seattle Steve]

ZFMax- Great info. Do you happen to have a comparison of the stock 245's to either the 285's or current 265's?