325/85R16 XML wheel size?

[AK_M1028]

I just bought a set of 325/85R16 Michelin XML tires for my M1028. Michelin recommends a 9" wheel, but doesn't offer any alternatives. The data I've seen says these are 38.7" x 12.9" tires when mounted on a 9" wide wheel. I am in the search for wheels right now. I heard that these tires do well aired down and will hold the bead even down low, so I don't plan on going with beadlocks.

How do you think they'll do with 8" wide wheels? Will they hold a bead better aired down on a skinnier wheel? Or should I try find a 9" to 10" wide wheel to get better contact area? I've read that the load capacity is 5,070# @ 65 psi to 3,600# @ 45 psi. I should be able to keep them somewhere between 30 and 40 psi for everyday driving.

Thanks in advance for your advice and comments.

 

[steelsoldiers]

Well, my tinkering with wheel size over the years has told me that running a skinny wheel will give you more sidewall bulge and rim protection, but will cause the tire to crown more and wear in the center on the highway. Therefore, fatter wheel will give you a flatter sidewall, less rim protection and less crown.

The old rule-of-thumb was don't run a tire on a rim that is less than 4" narrower than the tire. So, theoretically, you could run the XML's on a 8.9" rim or larger. That being said, I used to run 33x12.50 and 35x12.50 tires on my 8" wide CUCV rims and never lost a bead. I think you will have to run those tires real low off-road to get any sidewall flexibility.

Why don't you mount one on an 8" rim. Air it up and put the weight of your truck on it to see what it looks like?

 

[spicergear]

I had 37x13 Boggers on stock M715 wheels which may be a 7" wheel...worked, looked good, but had center bulge aired up.

 

[AJMBLAZER]

I say go with the 8's. Less fitment issues and you should be able to adjust the air pressure to get the tires to wear evenly long before you're endangering anything.

I just got a set of 11.00R16's and am planning on starting at 40psi and going down from there.


Just wondering but what are your plans for fitting these tires? I want to run them in the future after my 11.00R16's wear out and I actually have a garage I can fit a lifted CUCV on 38's in.

 

[AK_M1028]

I'm going to test fit a tire on a 8" wide wheels first. I read that for every 1/4" change of wheel width than 9", the tire changes 0.1". So 1" less wheel wide will change the tire height 0.4". So the 38.7" tire should become 39.1", I hope it doesn't crown too much. These tires are heavy, 122# each. I'm going to check the wheel weight difference between aluminum and steel. I want steel so I can paint them black, but may go aluminum if the weight savings is big. I suppose I could always powder coat the alumuinum wheels black.

I have a 5.5" Superlift kit that I am going to install and hope to clear the tires, but will trim if necessary. I don't want to use rear lift blocks, so...I have a 4" ORD shackle flip kit and 6" long shackles which should give me 5.5" lift in the rear with stock springs. I heard I may have binding issues with the longer shackles and the shackle flip kit, so I may use 1" Zero Rate Add a Leaves instead of the longer shackles.

I post up some pictures after I get it done. I should have the tires mounted by Thursday if I find wheels and get the lift kit installed before next weekend.

 

[AJMBLAZER]

Use the zero rates. Got a set sitting in my garage waiting for me to put them under the front. Make sure you call them and order some 3" wide zero rates since you have a 1-ton.

GET A STEERING BRACE!

Look around...I swear I've seen some 16x9's listed.



Oh yeah, and you can spray paint aluminum wheels. Take the clear off by either sanding or blasting them and then prime and paint them. A coat of clear or four would add to their durability. Haven't done it myself but have seen it done on other's vehicles. Nice way to revitalize factory wheels or change wheels so they match the vehicle without dropping the coin most powder coaters want.

 

[chevycrew]

Re: RE: 325/85R16 XML wheel size?

Make sure you call them and order some 3" wide zero rates since you have a 1-ton.

Since when did chevy's have 3" wide leaf springs. I have never seen one, but I havent seen it all either.

Running that size tire on an 8 wide wheel is no problem, you will have to run a lower pressure to get a decent contact patch. With the tire that high rated, I would start around 30lbs and go from there.

 

[AJMBLAZER]

RE: Re: RE: 325/85R16 XML wheel size?

The rear leafs on the 1 tons and very high GVWR 3/4 tons are 3" wide.

Fronts are the same 2.5" as the half and 3/4 tons.

http://www.offroaddesign.com/catalog/Zero Rates.htm

 

[chevycrew]

Id like to see a picture of those leafs. I have had many 3/4 and 1 ton truck. But all had 2 1/2 wide.

 

[CCATLETT1984]

well, if you ever saw the spring pack in a m1008 you'd see that its 3". very thick pack.

 

[Croatan_Kid]

Since you're doing the same as me and using a ORD shackle flip on the rear, don't forget to use the ZeroRates to move the axle back about an inch. Flipping the shackle over swings the rear end of the leaf pack downwards to make lift and at the same time pushes the center pin forward and that moves the axle forward. Also, as per every SFA Chevy, the front axle is about an inch (give or take depending) too far to the rear. If you move it forward (ZeroRates CAN be used on the front) that'll give you more room for what little big of articulation these trucks have and will avoid making contact with the rear of the fender. Just something for you to consider. Hope it helps

 

[AK_M1028]

Re: RE: 325/85R16 XML wheel size?

Why don't you mount one on an 8" rim. Air it up and put the weight of your truck on it to see what it looks like?

Well, I'm finally getting around to working on this again. I had a tire shop mount up a tire on a 16" x 8" wheel. It looks like the tire is crowning more than I'd like (with 25 psi), so I jacked it up in stock form to put some weight on it. I can't even fit the tire in the wheel well, it's too big. I guess I'll have to lift it before I can put some weight on it. From what I've seen so far, I'm going with a 16" x 9" or 16" x 10" wheel for these. I don't want the tire crowned out and wear out the center of the tread.

 

[rizzo]

RE: Re: RE: 325/85R16 XML wheel size?

some good info here. thanks everyone

 

[Croatan_Kid]

It won't wear out the center of the tire like you think it will. When you put it on the ground it will flatten out. 16x8s would be fine, but 16x10s would work better like you said. I put my 1100R16 XZLs on the stock 6.5 wide rims, they're pretty much flat and look and ride great.

 

[AJMBLAZER]

Frankly I'd rather run them on a 16x8 than a 16x10. Closer to the recommended size and won't stick the tire out into the fender as much.

 

[Croatan_Kid]

Agreed!

 

[K10A]

one prolem is the width of the bead in that it will not seat into the goove in the wheel. I have the 325s on the back and 11.00s on the front and i blow beads if i air down a lot. I heard to use windshield adhesive on the beads and it works as good as beadlocks but requires a press to disassemble.

 

[Croatan_Kid]

What do you have these tires on? I'd like to see a picture....you've peaked my curiousity!

 

[emr]

Well i might as well... i would run the 10's ive had alot of tires and would go with the tough looking tire, more girth, and doubt very much they will give u a problem either way really, Tightening them up just looks wierd to me? airing them down on a narrower rim seems to make more of an angle on the bead to me..weaker.., than a wider rim...Randy

 

[AJMBLAZER]

Narrower rim = more force holding the bead on the wheel's bead lip.

Narrow rim + wide tire = poor man's bead lock.


There's a reason you never see the "deep dish" wheels on the rock crawlers, sand runners, and actual trail runners in the 4x4 mags.