235/85/16 vs 265/75/16 for mileage on 4x4 E-350 - Diesel Forum

asander1 · 02-13-2006, 05:18 PM

I am going to be needing new tires soon and can't decide what size to get. When I got the van it had 235/85/16's which were fine but they were cheap tires and one of them had the tread separate on the highway which was kinda scary.

I then tried to put 285/75/16 Dueler Revos on but they were too big and hit the front leafs at full lock. I ended up putting 265/75/16 BFG A/Ts on and they have been very good. The wide tire technically should be better in the sand, but aired down I haven't noticed too much difference, but I didn't have the 235/85's that long.

Right now 90% of my driving is on the road and mostly the freeway. Offroading is mostly sand beaches and dirt roads, so I want something I can air down and perform well on the beach.

My biggest question is if going back to the narrower 235/85's will help highway milage vs the 265/75's or if it will not make much difference. I can get E load rating on the 235's also, vs only D on the 265's, this is for a 9,000 lb loaded E350 4x4 van so that may be an issue as well.

Any advice is much appreciated, thanks!

Andy

jerry350 · 02-13-2006, 08:51 PM

I'm running Cooper ATR's 265/75/16 and they do fine on the sand. I air down to 22lb. On the highway there stable and good traction. As far as fuel milege I can't help there I'm getting 12.5 a gal but I do like the 4.10s.

Jerry

msnunes · 02-14-2006, 09:34 AM

My understanding is that 235/85s will yield somewhat better highway mileage just from less tire on the ground. Don't know if they ride any better or not, but the sidewalls may be proportionally taller than the 265s, or about the same. I know my 265s ride a lot better than my stock 245s did.

As far as load rating, that may not make much difference, but I think you should be able to get 265 E's anyway. I believe my Michellins are...

**Dick Cutting** · 02-14-2006, 10:47 AM

235x85x15 and 265x75x16 tires are the same basic diameter, 31.7". They both come in LR "E". Just one is a bit wider than the other. My trucks are F-350 4x4 PU's.

My '97 has had 3 sets of the 235 x 85 x 16 LR "E" Steeltex's. First set I got 50k, the next set 62k and I still have the third set currently at 37k.

My '02 came with Steeltex 265x 75 x 16 LR "E" and I took the original set off at 71.3K. I just put another new set of them on because I've got a trip coming up in a couple of weeks and that set that I just took off had 69+K.

No problems whatsoever with the SteelTex's.

Dick

asander1 · 02-14-2006, 06:59 PM

Thanks for the information, looking a little more the 265/75/16 BFG A/T load range D has the same weight limits as the 235/85/16 E. So that may not be an issue, I did see some 265/75/16 BFG A/T load range E's on the BFG website, but haven't seen anyone online that sells them. Maybe they are special order.

So it sounds like the 235's might save a little fuel, but it doesn't sound overwhelming. I think I will stick with the wider 265's and make sure I run them at close to max. pressure for best economy on the freeway.

-Andy

bork · 02-16-2006, 07:25 AM

[ QUOTE ]
235x85x15 and 265x75x16 tires are the same basic diameter, 31.7". They both come in LR "E". Just one is a bit wider than the other. My trucks are F-350 4x4 PU's.

My '97 has had 3 sets of the 235 x 85 x 16 LR "E" Steeltex's. First set I got 50k, the next set 62k and I still have the third set currently at 37k.

My '02 came with Steeltex 265x 75 x 16 LR "E" and I took the original set off at 71.3K. I just put another new set of them on because I've got a trip coming up in a couple of weeks and that set that I just took off had 69+K.

No problems whatsoever with the SteelTex's.

Dick

[/ QUOTE ]

Who makes the Steeltex? & where ? & where purchased ?

Mr_Roboto · 02-16-2006, 07:39 AM

Firebomb, um, Firestone makes 'em. SteelTex's came on my new '02 F350, all 5 had crazy amounts of runout and wore like crazy because of it. IMO, they are cheap cheap tires.

**MikeL46** · 02-16-2006, 01:16 PM

[ QUOTE ]
Firebomb, um, Firestone makes 'em. SteelTex's came on my new '02 F350, all 5 had crazy amounts of runout and wore like crazy because of it. IMO, they are cheap cheap tires.

[/ QUOTE ]

I used to hate Firestone.

When I bought new trucks in 99 & 00 both came with Firestone Steeltex radials and I was very happy with the tires. They needed less wheel weights than the Michelins I had, wore quite well (50K+), tracked well, had adequate traction dry, wet and snow. I couldn't ask for much more in a truck tire.

Now I have ContiTracs on my van and I liked the Steeltex better.

Mike

AMMODYTE · 02-16-2006, 04:56 PM

I feel particularly qualified to answer your question, as I have a 4wd Econoline E-350 and 285/75R16 tires AND drive it on the beach a great deal.

You neglected to mention your differential ratio, and your engine, both of which are at least as significant as tire-size in estimating MPG.

The skinnier 235/85R16 tires will probably increase your highway MPG, but might well get you stuck in the sand, or even worse, develop weak areas in the sidewall from operating at reduced pressure, and threaten a blowout at highway speeds. The "85" profile tires will flex excessively in the sidewall area.

My 285/75R16 BFG A/T tires are load rated "D", despite an "E" rating being available for very little more. The sidewalls on the "E" tire are a little stiff, translating into poorer handling on soft sand.

I have Dana 60 differentials, with 4:10 gearing, and with the 285 tires I still only get 12 mpg on the highway. Undoubtedly, I would do better with a smaller contact patch and maybe a slightly taller profile ...but I'd sacrifice stopping distance, and soft-sand handling. I'm not an avid off-roader, just a surf-fisherman...so mud, rocks, grades and so forth mean very little to me.

I have a Quigley conversion, which retains the coil-springs, and I suspect the body was slightly lifted in a former life ...I haven't done a thing to the height except change the tires.

Long-winded. Bottom line? Stick with the 265/75R16 ...less tread "floats" better...air down to 12 psi. Don't start out with your wheel turned, stay in the track, and do not exceed 10 MPH. If your wheels start to spin, STOP. Don't dig in, cause YOU gonna have to dig OUT!

AMMO

asander1 · 02-18-2006, 08:01 PM

Ammo,

Thanks for the response, your van sounds very similar to mine, so the advice is probably right on. I have Dana 60's also with 4.10 gears. I have leafs up front, but that shouldn't matter much for this topic.

As you suggest I think I will stick with the 265/75R16's..

Thanks,

Andy