285/75R18 AT tires: A good choice for expedition-travel, domestic full-size trucks?

[Crazy Schooner]

I ran that size before, but on a compact truck. I went with Toyo MT's and I never ran into an issue with them. I liked how they were a true 35" tire. Previous to running 285/75's I ran 325/65R18 but I wanted slightly taller/narrower. I only got rid of them as I found I was able to run 15" rims on my lift, even though CST said otherwise. So I switched over to a 35x12.50R15 C rated tire. The Toyo's were mounted on a 18x9 setup.

 

[LJinLA]

I know the Coopers ST-Maxx's don't come in the 285/75R18, but have you looked one size up?
LT305/70R18 126\123Q E BLK 8.5 - 10 9 12.5 35.08 70 3750 18.5

I have a friend that is running that size of 'Maxx and he has nothing but good things to say. As you can see, they are a true 35" tall tire with a healthy 3750lb load rating. That is probably going to be the size I go with.
.
Jack

I currently have 16"x8" wheels on the truck, so if I opted to go with around 35" tall and 12.5" wide tires, the obvious choice for the ST-Maxx's would be:
LT315/75R16 127Q E BSW 34.45" 12.5" 8-11" 8.5" 18.5/32" E - 10 ply 3860 lbs 80 psi (Q) 99 mph 69 lbs Black 603
It's very close to the LT305/70/R18 you are suggesting, with just a taller sidewall, and I wouldn't have to buy a new set of expensive wheels. Besides, 18" tires cost way more than 16" tires in comparable sizes..

The only reason I would consider going with 18" tires with the added expense was to get them in size 285/75R18, which is the only way you can get a 35" tall tire that is just 11.5" wide. Think of a 285/75R16 (33" tire) that, still being 11.5" wide, is a full 2" taller (tire sidewall stays the same height, but you gain two inches in the 285/75R18 tires because the wheel, going from 16" to 18" inches rims, is two inches taller). Good size in my opinion, good compromise for long distance expedition-like travel that includes country roads, trails, and occasionally not-so-light trails. You can't get that (35" tall, 11.5" wide) with 16" tires or even 17" tires (the closest you can get to it with 17" tires is the 285/75R17, which is a bit less than 34" tall and 11.5" wide).

 

[LJinLA]

@ Crazy Schooner

Thanks for the input.. Great looking truck you got there!

 

[Olbuford]

I ran 315/75r16 BFG A/T KO's (not the new KO2) on my 99 Super Duty for years. Liked the first set so much that when it came time to replace, I got one of the few last sets of KO's. I ran them on the factory 16”x8” wheels with no issues and got about 70,000 miles out of them with regular rotation and balancing. The smaller rim width was great for airing down on the local beaches as a narrow rim acts like a poor man's beadlock. I'm a bit old school and like more sidewall and less rim diameter for the better ride quality and better aired down footprint. With the weight of a 3/4 ton truck with diesel, camper and gear I would be going for the wider footprint. Less chance of spinning tires and digging in (I.e. trail damage or getting stuck) and having to break out the recovery gear. The 285's with 18's May help your fuel economy some but it'll take the life of a set of tires (at least) to pay for a set of 18” wheels when you already have the 16's. Also, if you do upgrade to aftermarket wheels, check their max pressure and weight ratings. No sense having an E rated Tire when the rim itself can't hold the same load or be aired up to 80psi.

As to what brand? I had the Toyo's on my 2010 Super Duty and only got to use them once on the beach and once in the snow before the truck was totaled by a runaway engine (first and last 6.4 diesel I'll ever own). The tires were great on road and in wet conditions, did decent at the beach and excellent in the snow but couldn't tell you much about the long term as I only put about 8000 miles on them. I've run Tire shops most of my 16 years working which has let me get first hand info and feedback from lots of 4by owners up until a career change last year. I have had many people really happy with the Cooper AT/3 and the Open Country A/t but most of the folks bought them for the look. I'm not a fan of the BFG Ko2 as I convinced my dad to put them on his truck thinking they would be like the BFG's I had. Their performance was the same, if not slightly better but the longevity was not. He only got about 40k before needing to replace them. Right now my one truck has cooper discoverer and the other has a set of cheap Ironman A/t that are actually surprising me with their performance and longevity (bought cheap to get me through inspection and hold me over until I lift it for 37” meats). My vote would be either the Cooper A/T 3 or the Open Country A/T 2 in the 315/75r16.

Good luck and safe travels!

 

[LJinLA]

I ran 315/75r16 BFG A/T KO's (not the new KO2) on my 99 Super Duty for years. Liked the first set so much that when it came time to replace, I got one of the few last sets of KO's. I ran them on the factory 16”x8” wheels with no issues and got about 70,000 miles out of them with regular rotation and balancing. The smaller rim width was great for airing down on the local beaches as a narrow rim acts like a poor man's beadlock. I'm a bit old school and like more sidewall and less rim diameter for the better ride quality and better aired down footprint. With the weight of a 3/4 ton truck with diesel, camper and gear I would be going for the wider footprint. Less chance of spinning tires and digging in (I.e. trail damage or getting stuck) and having to break out the recovery gear. The 285's with 18's May help your fuel economy some but it'll take the life of a set of tires (at least) to pay for a set of 18” wheels when you already have the 16's. Also, if you do upgrade to aftermarket wheels, check their max pressure and weight ratings. No sense having an E rated Tire when the rim itself can't hold the same load or be aired up to 80psi.

As to what brand? I had the Toyo's on my 2010 Super Duty and only got to use them once on the beach and once in the snow before the truck was totaled by a runaway engine (first and last 6.4 diesel I'll ever own). The tires were great on road and in wet conditions, did decent at the beach and excellent in the snow but couldn't tell you much about the long term as I only put about 8000 miles on them. I've run Tire shops most of my 16 years working which has let me get first hand info and feedback from lots of 4by owners up until a career change last year. I have had many people really happy with the Cooper AT/3 and the Open Country A/t but most of the folks bought them for the look. I'm not a fan of the BFG Ko2 as I convinced my dad to put them on his truck thinking they would be like the BFG's I had. Their performance was the same, if not slightly better but the longevity was not. He only got about 40k before needing to replace them. Right now my one truck has cooper discoverer and the other has a set of cheap Ironman A/t that are actually surprising me with their performance and longevity (bought cheap to get me through inspection and hold me over until I lift it for 37” meats). My vote would be either the Cooper A/T 3 or the Open Country A/T 2 in the 315/75r16.

Good luck and safe travels!

Olbuford, thanks so very much for your thoughtful and thorough post. I find myself agreeing with the various arguments you presented. Besides, the 315/75R16 is a readily available tire size, available from many manufacturers, and is also very common abroad (Mexico, South America, etc.), while the same things cannot be said of the 285/75R18. I have read the same comments you made in regard to the BFG A/T KO2's from several different sources (brittle, non durable tire components which lead to a short tire life, plus there have been a few cases with these tires literally exploding on the highway before their expected life mileage), so it's something I'd stay away from when it comes to full-size trucks. I just checked prices on Amazon for the 315/75R16 size in both the Toyo AT2's ($238) and the Cooper AT3's ($219), and they are a bit cheaper than the 285/75R18's, about $60 per tire. (The Cooper ST Maxx is around $275 in 315/75R16, and it seems to get much better reviews as far as durability and performance both on road and off road than the Cooper AT3 and Toyo AT2). Good to hear that you ran your 315/75R16's on OEM 16x8 wheels satisfactorily. One thing, though, is that the BFG tires tend to be smaller than their advertised size; on the other hand, the Toyo AT2's in 315/75R16 tend to be a true 34.6" x 12.3", not sure if the same is true of the Cooper AT3's and ST Maxx's, and that may change things a bit when running them on OEM 16x8 wheels, or it may not. Proper tire clearance boils down to proper wheel backspacing/offset. If I recall correctly, the 2nd gen Dodge Ram 16x8 wheels have a backspacing of 5.25", I'm not sure if that would be good enough to properly clear true size 315/75R16 tires on these trucks (I was hoping to get this kind of info from other 2nd gen Ram owners here..).

Thanks again for your feedback, good food for thought!

 

[rruff]

Olbuford, thanks so very much for your thoughtful and thorough post. I find myself agreeing with the various arguments you presented. Besides, the 315/75R16 is a readily available tire size, available from many manufacturers, and is also very common abroad (Mexico, South America, etc.), while the same things cannot be said of the 285/75R18.

I totally agree with this. Go with 16". Cheaper, more common, better offroad ride, more sidewall, etc. You could also consider 17" if you can get rims that work, with 315/70r17s. Nominally just a couple tenths smaller in diameter than the 315/75r16s. I was stuck with 18"+ on my truck, but would have gotten smaller rims if I could have.

As for the tires, the ST Maxx will get worse mpg and be louder, and also be more durable. It's more of a AT-mud hybrid. There's always a tradeoff. Unfortunately it's hard to tell from specs on tires what the mpg hit will be. And if you are going to be on the road a lot and don't need mud performance I'd stick with milder ATs.

Some others I'd suggest you consider in E rated 315/75r16 are:

Falken Wildpeak AT3W
Mastercraft Courser AXT
Yokohama Geolander AT G015

These are more hybrid mud/AT:

Mastercraft Courser CXT
Mickey Thompson Baja ATZ P3

https://tiresize.com/tiresizes/35-inch-tires/

 

[LJinLA]

I totally agree with this. Go with 16". Cheaper, more common, better offroad ride, more sidewall, etc. You could also consider 17" if you can get rims that work, with 315/70r17s. Nominally just a couple tenths smaller in diameter than the 315/75r16s. I was stuck with 18"+ on my truck, but would have gotten smaller rims if I could have.

As for the tires, the ST Maxx will get worse mpg and be louder, and also be more durable. It's more of a AT-mud hybrid. There's always a tradeoff. Unfortunately it's hard to tell from specs on tires what the mpg hit will be. And if you are going to be on the road a lot and don't need mud performance I'd stick with milder ATs.

Some others I'd suggest you consider in E rated 315/75r16 are:

Falken Wildpeak AT3W
Mastercraft Courser AXT
Yokohama Geolander AT G015

These are more hybrid mud/AT:

Mastercraft Courser CXT
Mickey Thompson Baja ATZ P3

https://tiresize.com/tiresizes/35-inch-tires/

After considering what has been recently said, I am leaning again toward 315/75R16 tires..
With the 315/70R17's you lose some in tire load rating and sidewall height, so I don't see any reason for going up to 17" rims in this case.

Also, I'd like to avoid having the tires stick out from the wheel wells as it creates a mess on the sides of the truck when going over mud, dirty water, etc. I just read a build thread by a previous member of this forum (1 speed/Jim Feehan) who used 315/75R16 tires with Hummer 16" wheels (5.5" backspacing) for his expedition truck and documented with pictures how the 315's got nicely tucked inside the wheel wells of his 2nd gen Dodge Ram, claiming no rubbing problems whatsoever. I think he had a two- or three-inch front lift. That may work nicely. Anybody reading this has used this combination on his 2nd gen Ram?

[Edit 3/29/2018: I got mixed up...re-checked that info and 1 speed/Jim Feehan did certainly NOT use 315/75R16 tires on H1 (16.5") rims. Sorry about it.]

An AT-mud hybrid may work a little better for this truck's purpose, as it will see country roads and some light trails with possible mud in the way. I have read that AT tires such as the Toyo AT2's don't do too well in even light mud, often getting stuck. So perhaps the ST Maxx's, Courser CXT and MTB ATZ P3 are well worth considering.

Thanks for suggesting the alternative tires, I'll look into them..

 

[locrwln]

I currently have 16"x8" wheels on the truck, so if I opted to go with around 35" tall and 12.5" wide tires, the obvious choice for the ST-Maxx's would be:
LT315/75R16 127Q E BSW 34.45" 12.5" 8-11" 8.5" 18.5/32" E - 10 ply 3860 lbs 80 psi (Q) 99 mph 69 lbs Black 603
It's very close to the LT305/70/R18 you are suggesting, with just a taller sidewall, and I wouldn't have to buy a new set of expensive wheels. Besides, 18" tires cost way more than 16" tires in comparable sizes..

The only reason I would consider going with 18" tires with the added expense was to get them in size 285/75R18, which is the only way you can get a 35" tall tire that is just 11.5" wide. Think of a 285/75R16 (33" tire) that, still being 11.5" wide, is a full 2" taller (tire sidewall stays the same height, but you gain two inches in the 285/75R18 tires because the wheel, going from 16" to 18" inches rims, is two inches taller). Good size in my opinion, good compromise for long distance expedition-like travel that includes country roads, trails, and occasionally not-so-light trails. You can't get that (35" tall, 11.5" wide) with 16" tires or even 17" tires (the closest you can get to it with 17" tires is the 285/75R17, which is a bit less than 34" tall and 11.5" wide).

I merely threw the 305 out as an option because you were looking at 18's and 315/75R16, which would have been between those two tires in width. I know all about the 285/75R17's as I have ran two sets on my truck. Like you, I like the narrow width, but in 17's, these are largest E1 load rated tire in a ~34-35" range.

After considering what has been recently said, I am leaning again toward 315/75R16 tires..
With the 315/70R17's you lose some in tire load rating and sidewall height, so I don't see any reason for going up to 17" rims in this case.

Also, I'd like to avoid having the tires stick out from the wheel wells as it creates a mess on the sides of the truck when going over mud, dirty water, etc. I just read a build thread by a previous member of this forum (1 speed/Jim Feehan) who used 315/75R16 tires with Hummer 16" wheels (5.5" backspacing) for his expedition truck and documented with pictures how the 315's got nicely tucked inside the wheel wells of his 2nd gen Dodge Ram, claiming no rubbing problems whatsoever. I think he had a two- or three-inch front lift. That may work nicely. Anybody reading this has used this combination on his 2nd gen Ram?

An AT-mud hybrid may work a little better for this truck's purpose, as it will see country roads and some light trails with possible mud in the way. I have read that AT tires such as the Toyo AT2's don't do too well in even light mud, often getting stuck. So perhaps the ST Maxx's, Courser CXT and MTB ATZ P3 are well worth considering.

Thanks for suggesting the alternative tires, I'll look into them..

Hummer rims don't come in 16". H-1's are 16.5" or H2's (what I was running on my truck) are 17's.
.
I am looking at moving up to the 18's specifically to get a relatively narrow/true 35" tire with a decent load rating. I can't run a 16" rim on my truck, 17's are as small as I can go.
.
Jack

 

[Darwin]

I have ran both the Toyo 315/75/16 Toyo MT on one 95 Ram CTD with auto, and now as you see in my sig 295/75/18 Coopers with my 97. It's hard to directly compare the two because of the two different trucks one being an auto the other a manual.

1.) do not expect better fuel mileage with any of the tires you have listed, I got the best mileage with the tiny stock tires that came on the truck originally.

2.) I have 3.55 gears, and if given the choice I would do 4.10 gears. The mileage really suffers around town with 3.55's and I like the way the truck drove when it had the stock tires. 4.10 would probably put back to the same driving charecteristics as stock.

3.) the Toyos MT where a bomb proof tire, I got great mileage out of them but they were louder. The Coopers are also lasting a long time. I have a heavy camper on 95% of the time and I will get just right at 50K miles out of them including two trips around Mexico. That's damn good in my opinion.

4.) I would do away with the 2 inch thuren lift if doing over and try to move the axle forward as far possible instead to squeeze the tires on, but if you are not carrying a lot of weight maybe in your situation the thurens would be okay. I still prefer the least amount of lift.

5.) the best ride in my opinion comes from having really good shocks and a tire with some sidewall aired down offroad.

6.)If you need the carrying capacity the 285/75/18's AND my Coopers have the highest load capacity.

7.) I think 285/75/16 represents a good compromise.

 

[rayra]

besides highe rpricing, what's the global availability of 18" tires, as opposed to 16" or 17". How hard would it be in some third-world country to get a particular sized tire? I think that would be my greatest concern / curiousity, building a private non-sponsored expedition vehicle. Same for any other non-standard suspension or drive-train components

 

[LJinLA]

Hummer rims don't come in 16". H-1's are 16.5" or H2's (what I was running on my truck) are 17's.

Thanks for pointing this out. In his thread, "1 speed" stated that he was using H1 rims with 315/75R16 tires, and I assumed those were 16" wheels. So, if H1 wheels are 16.5" tall, it appears that he used 16" tires on 16.5" wheels. It seems to have worked perfectly for him, though.

[Edit 3/29/2018: I got mixed up...re-checked that info today and 1 speed/Jim Feehan never used 315/75R16 tires on H1 (16.5") rims. Sorry about it.]

I am looking at moving up to the 18's specifically to get a relatively narrow/true 35" tire with a decent load rating. I can't run a 16" rim on my truck, 17's are as small as I can go

That is precisely the idea I started this thread with, getting a true 35" tire that is only 11.5" wide, having assumed there were substantial benefits in using a tall, narrow tire for expedition-like travel.

 

[LJinLA]

I have ran both the Toyo 315/75/16 Toyo MT on one 95 Ram CTD with auto, and now as you see in my sig 295/75/18 Coopers with my 97. It's hard to directly compare the two because of the two different trucks one being an auto the other a manual.

1.) do not expect better fuel mileage with any of the tires you have listed, I got the best mileage with the tiny stock tires that came on the truck originally.

2.) I have 3.55 gears, and if given the choice I would do 4.10 gears. The mileage really suffers around town with 3.55's and I like the way the truck drove when it had the stock tires. 4.10 would probably put back to the same driving charecteristics as stock.

3.) the Toyos MT where a bomb proof tire, I got great mileage out of them but they were louder. The Coopers are also lasting a long time. I have a heavy camper on 95% of the time and I will get just right at 50K miles out of them including two trips around Mexico. That's damn good in my opinion.

4.) I would do away with the 2 inch thuren lift if doing over and try to move the axle forward as far possible instead to squeeze the tires on, but if you are not carrying a lot of weight maybe in your situation the thurens would be okay. I still prefer the least amount of lift.

5.) the best ride in my opinion comes from having really good shocks and a tire with some sidewall aired down offroad.

6.)If you need the carrying capacity the 285/75/18's AND my Coopers have the highest load capacity.

7.) I think 285/75/16 represents a good compromise.

Thanks so much for your feedback!

Do you remember what wheels and what wheel backspacing or offset you used for those Toyo MT 315/75R16 tires? I think those are the biggest 315/75R16 tires you can find, true size 34.9"x12.9" tires, and it would be interesting to know that information and whether you experienced any on-road/off-road rubbing driving your 2nd gen Ram with that combination. I am well aware of the reputation they have as bomb proof and high-durability tires.

If you carry a heavy camper or tow heavily, 4.10's may be better than 3.55's with 35" tires..

Centering the front wheels under the wheel wells is the very best way to allow for large tires, and I think that a good quality 2" front lift helps too along the way. I prefer the least amount of lift too.

285/75R16's (32.8"x11.5") fit easily on a 2nd gen Ram, basically you need do nothing other than mount them on 8" OEM wheels, but then, wouldn't a 255/85R16 tire be even better, mounted on OEM steel wheels (still about 33" tall and only about 10" wide..), when it comes to 33" tires?

 

[LJinLA]

besides highe rpricing, what's the global availability of 18" tires, as opposed to 16" or 17". How hard would it be in some third-world country to get a particular sized tire? I think that would be my greatest concern / curiousity, building a private non-sponsored expedition vehicle. Same for any other non-standard suspension or drive-train components

Sure, from this perspective, a commonly available 16" tire such as the 315/75R16 or 285/75R16 wins hands down over the newer, less available sizes such as the 285/75R18.. Same is true for all other truck components.

 

[rayra]

I'd thought I'd read mention of foreign travel when I skimmed the topic, true 'expedition' driving. Staying in the states I wouldn't much worry about tire availability. Except in the hinterlands of Canada or the inter-mountain West.


Forgot to comment on width. Two primary factors. Your 'pizza cutter' tires will have less rolling resistance and could afford an increase in mpg. No small consideration if your trips will be treks of thousands of miles. Particularly when 95%+ of the travel will be on paved roads. The other major consideration is the terrain you'll mostly be using the vehicle in. Do you want to cut thru light snow and mud to get traction, or do you need flotation / less ground pressure over worse mud / snow and sand? Everything else about it is just style points.

 

[rruff]

Your 'pizza cutter' tires will have less rolling resistance and could afford an increase in mpg.

Actually wider tires have lower rolling resistance on the street, all else being equal. It isn't a big enough difference to worry about, though.