4x4 E350 w/ D rated tires - opinions sought

pbjosh · 10-09-2016, 07:30 AM

Heya folks,

I've got a 96 E350 RB (7.3), that I homebrewed into a fauxmobile. Relevant stats:

-About 8300lbs curb weight, front heavy (roughly 4300/4000 split).

-In Peru. This is the most significant part as it really limits availability.

-Probably 60/40 blend of pavement/dirt driving.

-The non-pavement is almost all just dirt road, and when I use 4L it is invariably mud or stream crossings (cobbles), very rarely anything gnarly. I use low range all the time just due to steep terrain, though I don't lock the hubs most of the time. I lock the hubs maybe once/week.

-Rarely drive on sharp stuff where I worry about a puncture - maybe once in the last year was I on a really bad 4WD track with lots of sharp rocks, but even that was easily navigated to not have any sidewall contact. No gouges in the sidewalls of my now-on-last-legs tires.

-Rarely drive at high speed (roads just do not allow it here) but will be on better roads in Brazil, Argentina and Chile in the future. When I say rarely at high speed, it is perhaps a few times a year that I am able to exceed 45-50mph, and the vast majority of my driving, even on pavement, is under 35mph. Will probably drive up to 50-60 more in the future, but 70+ just will never happen down here.

-Lots of the on-road driving (really, almost all of it) is super twisty and up and down (the Andes).

-285/70R17 (or 285/75R17 of course) tire size

I need new tires and I do not think it is prudent to wait until Chile or Brazil where there may be more or better options. I am worn to slick on the inside of two of my tires. It would be a few thousand miles more to get to Rio Branco or Porto Velho in Brazil. In Peru my options are really limited for my size.

Best two options are a Pirelli Scorpion A/T and a Falken Wildpeak A/T. Both are 121 load rating (3195 lbs) which is fine, same as my current BFG's. But both are D rated, a softer sidewall. I am not hugely concerned about punctures, but should I be overly concerned about blowouts or more body roll due to softer sidewall? My van weighs less than a lot of 4x4 Sportsmobiles and I use 4x4 basically exclusively for mud and creeks, because the places I want to go are universally on bad dirt roads. No serious four-wheeling, I've never needed to dig or use my winch, but I use 4L a lot in mud.

The only other option, and it is not yet clear if they are actually available, is that perhaps I could pay over $500/tire for BFG M/T's. Price aside, I do not like this option as they will wear too fast - I am headed south and will be more on pavement and when on pavement, for longer distances. Would really love an E-rated A/T tire, but there just is nothing available except for one Chinese brand and my instinct tells me a D-rated Pirelli is a safer bet than an E-rated Chinese no-name brand.

I really appreciate any and all opinions. I was hoping to hold out and get tires in Brazil but I would have to radically change plans and miss a lot that I want to see in Peru to hurry to Brazil, or make a week long round trip to Chile (several hundred in gas just to do that plus border hassle, and no guarantee the size is actually available there).

Cheers,
Josh

REF · 10-09-2016, 08:56 AM

Initial thoughts would be to wait and get E, but that may not be practical in your situation. You can certainly get by with D, many of us have, but it's pushing the load limit and as you said, the sidewall ply is a concern. I personally wouldn't run them on my rig again, but I'm pushing 10K lbs. Any way to find 2 used tires in your size in better shape to get you through in the meantime? Check with the tire shop. Another concern would be why you're wearing the inside of your tires bald to avoid it happening with a new set, is it front or rear? Possible overloaded or tired springs, worn shocks, bad ball joints, improper alignment or any worn front bushings are all possible culprits to look at. Good luck, sounds like a great adventure, one we plan on taking some day.

pbjosh · 10-09-2016, 09:20 AM

No chance at all of finding used here. 17" rims are pretty unheard of in Peru, it seems. Largest widely available sizes are variations on 265/XXR16, from there it goes straight to commercial heavy truck tires.

I ultimately think I will have to suck it up and buy the D's. They are about 30% more expensive than they would be in the US but that is par for the course for anything vehicle related in Latin America, except labor. If they don't work out well and I can find better E rated tires later, I will still come out around the same price or cheaper than paying over $2k for BFG M/T's now.

deserteagle56 · 10-09-2016, 09:35 AM

For your driving conditions? If you can at all find them, Toyo Open Country M/Ts. Over the past few years all the mines here in northern Nevada have standardized on them. Or the Toyo M55 series. No other easily available tire can take the punishment they can and still hold air.

pbjosh · 10-09-2016, 09:59 AM

No chance of finding that tire here. This isn't a game of what is the ideal tire

It's a game of who here would buy the D rated tires and who would jump through flames to try to get to another country, radically altering their plans, on the chance of finding better than D rated.

1der · 10-09-2016, 01:34 PM

How about finding two cheap 16" rims and tires that will work for the short term? Have the bald tires dismounted or use for spares until you get to where the 17" ones are available.

What is the cost of shipping from the US and what is the duty on a used set of tires coming in? Seems like there are sets of 285/17's that show up on the classifieds/Craigslist.

Just thinking out of the box😊

carringb · 10-09-2016, 02:17 PM

For your weight, Load Range D is sufficient. Plus, the lower speeds only help in that regard. At max PSI, they are good for nearly 6,200 pounds per axle. Many of the true SMB builds will exceed that empty, however 6,200 is still more than the OEM 245 tires rated at 6,084 pounds per axle.

pbjosh · 10-09-2016, 03:01 PM

Quote:

Originally Posted by 1der

How about finding two cheap 16" rims and tires that will work for the short term? Have the bald tires dismounted or use for spares until you get to where the 17" ones are available.

What is the cost of shipping from the US and what is the duty on a used set of tires coming in? Seems like there are sets of 285/17's that show up on the classifieds/Craigslist.

Just thinking out of the box😊

If shipping/importing were a realistic option, cost or time wise, I'd just get a good set of new tires in exchange for the effort, but it would be way cheaper and faster to drive to Chile than fart around with shipping tires... I've mulled just switching back to 16" rims period, but I do quite like larger tires for better clearance and traction.

pbjosh · 10-09-2016, 03:05 PM

Quote:

Originally Posted by carringb

For your weight, Load Range D is sufficient. Plus, the lower speeds only help in that regard. At max PSI, they are good for nearly 6,200 pounds per axle. Many of the true SMB builds will exceed that empty, however 6,200 is still more than the OEM 245 tires rated at 6,084 pounds per axle.

Appreciate your and all others' opinions!

I'd much rather have an E tire, but at my weight, I think this logic bears out reasonably. It really is uncommon for me to get up over about 30-35mph. I do worry a bit about the heat from some highway driving in Brazil at low elevations (ie 90-95F) and decent speeds (maybe 50-60mph at times with luck), and I worry about blowout likelihood for the occasional, inevitable hard pothole/speedbump encounter.

Cheers again all,
Josh

carringb · 10-09-2016, 04:08 PM

90-95F still isn't that hot, even though the humidity may make it feel that way.

I have had to slow down in hot weather (115F) due to my trailer tires getting too hot to touch, but that was also due to the 75 MPH speed limit, and the drivers from Southern California who get hostile to anybody not going 10-over.

Speed make tires hotter more than ambient temp, so between the slow speeds and adequate weight rating, I really think you'll be ok.

For sidewall strength, the make of the tire can matter as much or more than the load range. I run Toyo M55 because of that, as do nearly all forestry companies in the NW. But, they don't have as many size options compared to other tires, and don't come with a mileage warranty (even though I get roughly double the miles I used to get running Open Country A/Ts).

For rough roads, I think you'll be better served with an A/T and not an M/T. M/T really kinda suck at anything besides mud and really wet snow. On rough and un-paved roads, they tend to "chunk" easier than a good A/T, plus they have worse traction on pavement, gravel, and dry dirt.