help with my drive tire choice

An irgnorant nation will never be free. Thomas Jefferson

 

Is an "irgnorant" nation one that can't spell "ignorant"? Sorry, couldn't resist.

 

Its my weakness spelling! But thanks for understanding.

 

When you're stuck in the dirt because your tires don't have enough grip to walk the truck back out to the road, you are getting 0 mpg. You are also missing loads, which in some cases adds up to unpaid miles. Especially in a "wet" year, I'd lose more money with a "low rolling resistance" tire that doesn't have any grip than I would with a "high rolling resistance" tire that is unstoppable. Every time you get stuck, you've got to look for somebody to pull you out and HOPE they have someTHING to pull you out with....and sometimes all they can find is a rusty old 1/4" chain of unknown strength, so you take your chances. I carry a 20' long 3/8" G70 chain...so all I need is somebody and another vehicle capable of pulling me out...but you STILL risk tearing stuff up each and every time you get stuck...which again, costs money. Those couple hours it took to get the truck unstuck means that the quarry where you were going to get your load home at the end of the day is closed by the time you get there, or that the job site you were hauling into will be locked up by the time you get there, so rather than being paid to drive home at the end of the day you are bouncing home empty and eating 100% of the fuel cost to get you there. I got stuck twice in the first week I had the DR444's on my truck. It was embarrassing, considering the worn out tires I had just pulled off would have easily walked through what stopped me. The chain in my side box is typically used 95% of the time to pull out OTHER trucks that have got stuck...but since going to the DR444? 100% of its use has been to pull ME out. Like I said...embarrassing. No off-road grip at all with these tires.

What's my point?

Fuel mileage isn't the ONLY game in town. Of course for a long-haul truck that never ventures off-pavement it plays a much larger roll than in a local truck that returns home most every night and gets to play in the dirt several times per day. Every operation is different, though, and each truck owner might prioritize the various options available in a different manner. You value fuel mileage above all else. I would imagine that means you're also doing other fuel-mileage oriented things with your truck such as running crazy high gear ratios in the 2.xx range and either a direct-drive transmission or you just don't use your "overdrive" gears because they are less "efficient", and obstructing traffic as you drive well below both the speed limit and the natural flow of traffic in order to squeeze as many miles as you possibly can out of each gallon of fuel you buy. For a highway trucker, that is a perfectly rational business decision. I run 4.17 rears and contemplating swapping them out for 4.42's, and I run within 2-3 mph of the speed limit no matter what the speed limit might be. My priorities as a local bulk-hauler (tanks & dumps) is different...time is money, and in my operation I couldn't save enough fuel to pay for the extra time it would cost me or the lost revenues from the missed loads that I couldn't get to because I took too long dragging my feet all day. That doesn't mean your priorities are wrong, just that your operation differs from mine. The OP's operation might also be different, and so it really doesn't add anything at all to this thread preaching about fuel mileage if fuel mileage isn't one of his top priorities.

I do have one question about your math, though. In order to "save" $10,000 in 2 years, at $4/gallon, you'd have to gain at least .5 mpg just in the tire swap alone...not considering any other factors which might also affect fuel mileage...in order to even come close to that. When you add in the cost of replacing the tires in fewer miles, the mpg "savings" has to be even greater in order to still "save" as much as you think you might be saving. For example, if the tires have a similar purchase price but only last half as long, you could be looking at a full mpg difference (or more) you'll have to make up JUST to save that $10,000 in 2 years because the tire's cost-per-mile is so much greater. So the question I've never been able to find the answer to is just how much fuel-mileage difference is there for every 10 points on the rolling resistance? The drive tires the OP is looking at are in the 130-140 range, while you state your tires are down in there at 95. I've never been able to find any explanation as to how those numbers were calculated or what they ACTUALLY mean in real-world results. What sort of fuel savings could one expect from putting a 95 RR tire on their truck instead of a 140 RR tire? What does the 45 RR difference mean in ACTUAL fuel mileage results?

 

Brigstone m710 RR 98, deep lug. Get both low RR and lug and deep tread.

 

Pedigree , in the 140 to 95 RR switch , one should be looking at .5 to .6 mpg. And trucks have to be specked for the job at hand. His truck aimed at fuel mileage in OTR would stink in your job. As your truck would in his role. But tires are some thing that has to be bought ! Try to get best for conditions. In OTR , if you just bought a truck with the wrong tires(new) , it can be cheaper to pull them off day one to get better RR . The savings would pay for the new ones , and the next set.
If you can , you may want to find some one to buy your bearly used tires . For something that will suit your job better . If they can not do their job they are worthless! I have ran some mining tires that started at , if I rem correct , at 42/32s . Nothing stopped her! But she was 100% off road.

 

That does seem odd for that tread to have such low RR. And while not as deep lug as some, it's 26/32 new. What's the catch? Surely there's a downside here, besides the slightly higher price.

 

http://locator.michelintruck.com/RRListings.aspx

M710 on drives look good on paper

 

Im willing to bet that being an open shoulder (M710) that you wont see the expected mileage you might think you will get out of it...

 

The one I saw on bridgestones site was closed shoulder.