15" vs 17" wheel with 39.5 IROKS

[78-FJ40]

I'm going to be linking the rear of the cruiser soon and going from 37" IROKS on a 15" wheel to the 39.5" IROKS. Looking for some input on whether to buy the 15" or 17" IROKS. I have 15x10 wheels with Staun beadlocks so the 39.5x13.50x15 are really attractive, but that's a lot of tire on a 15" wheel. Any experienced opinions out there on pros/cons of a 15 vs 17 wheel with 39.5's?

Thanks,
John

 

['74 UA FJ]

I have problems at really low pressures with the inner bead of my 38.5 SXs leaking when crawling over rocks a certain way. I have regular outer beadlocks, though. I wouldn't think you'd have an issue with Stauns. I don't think the increased sidewall height will make a difference at low speed crawling as long as you can keep the tire on the bead.

 

[Mace]

You'll "push" a bit in corners. the 39x 17 will grab slightly harder. But, if the stauns are a smokin deal, I'd opt for them.

 

[mookie]

i don't understand it but according to the interco website the 39.5 x 17 irok weighs 84 lbs......the 15" version is 76.......and you know that the 17" wheel is going to weigh more than a 15". if your running yota axles then go as light as you can on tires/wheels imo.

as far as the sx's burping air, that's a whole 'nother animal.....i had the same issue when i had sx's....never had an issue since i switched to iroks on the same wheels.

 

[ACC Toyota]

Here is a set of 17s w/ 39" iroks that we installed on a 40 about a year ago. They seam to work well. I wouldn't buy 15' wheels again if it were me.

 

[Tapage]

market it's moving to the 17" wheel .. more options better prices .?

 

[yzftaco]

This is what motivated me to get 17" wheels...

Plus with the 17's the tires look right. Not big ol balloons

market it's moving to the 17" wheel .. more options better prices .?

 

[LCOwner]

market it's moving to the 17" wheel .. more options better prices .?

^^^^^
This

 

[Slowerthanu]

15's are history, 17's are the norm and 20's are getting popular on 40's and up.

15's have brake clearance issues where 17's have miles of room.

Stick with Stauns, when I bought my 37x17's the Stauns were back ordered so I went with Allieds. The single bead lock is not only half the bead lock, but it is always gonna be out of round and a bigger bitch to maintain.

 

[Mace]

If it's from a cost perspective, he already has the 15" rims. So it'll be a heck of a lot cheaper to stick with the 15's.

so, leaving cost out.

There is not a huge performance difference between 15 and 17" rims with a 40" tire.

As far as ballooning, My 39.5x16.5 Irocks are balloons (another 1/2-in is not going to make a difference).. And the 15" variety are lighter.

IMHO, stick with your current rims and get the 39.5's

If you want a specific tire that is not produced in a 15-in rim, then you need to change rims.

 

[Mace]

If it's from a cost perspective, he already has the 15" rims. So it'll be a heck of a lot cheaper to stick with the 15's.

so, leaving cost out.

There is not a huge performance difference between 15 and 17" rims with a 40" tire.

As far as ballooning, My 39.5x16.5 Irocks are balloons (another 1/2-in is not going to make a difference).. And the 15" variety are lighter.

IMHO, stick with your current rims and get the 39.5's

If you want a specific tire that is not produced in a 15-in rim, then you need to change rims.

 

[4rnr]

I vote 17's. I think the added side wall control will help a lot while turning, and staying on the line you want, especially at super low pressures when the tire can wrinkle up a lot. 17's will also decrease tire roll on side hills.

I drive on the street a lot. And here in the Chicago area the driving has to be aggressive and quick. I think when I go 17's the truck should feel more planted and responsive.

 

[mookie]

i have bent everyone of my beadlock rings on my 15" rimsat one time or another.....i wonder if that issue would be worse with the same size tire on 17's?

 

['74 UA FJ]

i have bent everyone of my beadlock rings on my 15" rimsat one time or another.....i wonder if that issue would be worse with the same size tire on 17's?

I would bet it would be worse. The rim is closer to the rocks. There is a larger area on the ring to bend.

 

[Mace]

A whole 1" is not gonna make a difference. The difference is how well the rim is built. If it's crappy, it'll still bend.

 

['74 UA FJ]

A whole 1" is not gonna make a difference. The difference is how well the rim is built. If it's crappy, it'll still bend.

Looking at the numbers, it will be worse with two equally built wheels. That difference may be negligable, but it will still be there.

 

[Mace]

Looking at the numbers, it will be worse with two equally built wheels. That difference may be negligable, but it will still be there.

What are you basing your numbers on?

 

[fj40charles]

Looking at the numbers, it will be worse with two equally built wheels. That difference may be negligable, but it will still be there.

Can you provide the numbers? What calculation are you basing this on?

 

[78-FJ40]

If it's from a cost perspective, he already has the 15" rims. So it'll be a heck of a lot cheaper to stick with the 15's.

so, leaving cost out.

There is not a huge performance difference between 15 and 17" rims with a 40" tire.

As far as ballooning, My 39.5x16.5 Irocks are balloons (another 1/2-in is not going to make a difference).. And the 15" variety are lighter.

IMHO, stick with your current rims and get the 39.5's

If you want a specific tire that is not produced in a 15-in rim, then you need to change rims.

That's what I was really curious about. I can afford to go either way, but I have the Stauns for 15" wheels. I don't have any for 17" wheels and they are no longer being made. If the performance off road with the 39's and 15's is comparable to with 17's, then that's what I wanted to know. The truck is used 95% off road so on road performance is a non-issue.

Thanks

 

[mookie]

A whole 1" is not gonna make a difference. The difference is how well the rim is built. If it's crappy, it'll still bend.

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