I had this thread started in the SUV section, and its2slo mentioned that 15" rims are better when aired down, providing more surface area to the ground or something like that.

I just thought I'd see if anyone could expand on that, and/or offer any other benefits of one size over the other when off-road.

 

I kind of agree with that statement. Assuming the outside tread diameter is the same, a 15 gives you more sidewall to work with and maybe more tread on the ground legnthwise.

\_________/ with 15" at trail pressure

\______/ with a 16" at the same pressure

I'm no physics professor but it might be true. There's lots of other factors to figure in like vehicle weight, sidewall stiffness, wheel width, etc. Again, assuming same aired down pressure and same tread diameter at high pressure.

A strong arguement for running 15s is tire price for the same tread diameter. 16s are sometimes $25 more for the same outside diameter tire.

The real question is, will your brake calipers rub if you try to put 15s on a rig that came with 16s.

 

yeah, i was wondering about that too. i have 16s now, but i was considering going to 15s someday...

 

That's the thing about the rims Wheeler's offers. They say that they are built so that you can run 15" rims on a vehicle that was stock with 16" rims.

Check it out right here.

 

Smaller rim, more sidewall as Matt said.

Advantage is wider footprint with more sidewall.

I saw the Wheeler post. I thought it a bit odd that they are claiming to have something designed to fit. Either it does, or it doesn't. I am not familiar with exact fitment issues, but it seems interesting that they know a magic way to fit around something that required 16 inches with something that is now 15"

 

I agree, and that's a good point. I'll e-mail them tomorrow for some more info. Gary Wheeler has been really good with replying to e-mails, so I'm sure I can get an answer quickly.

 

If they fit the larger brakes that may or may not be on some 3rd gens those seem perfect.

Aurora Sandman, '02 CO4RJ participant, has a 2002 Runner and runs 15 inch wheels if im not mistaken. I think he told me he had to get a base model with smaller brakes to get the 15s. I'll ask him to be sure.

 

I totally missed your thread on the SUV board. Sorry, I skip a lot since there are so many new threads and new posts there every day. Some just fall through the cracks.

I think this new offroading based board is a hit!!

 

So, to go back to the original question: what are the benefits of 15" over 16" rims or versa visa?

( I've got 15" alloy rims on my runner but I've got a set of 16" steel split rims to clean up)

 

the reason i said whatever to the tread contact is because i feel that 1" more sidewall isnt gonna make that much difference so i sure wouldnt go and get 15's for that reason.
i should also clarify that the 4wheelphux rock crawlers hit the calipers on my taco that came with 15's, so even with the spacer i dont think you 16 guys could use their 15's. good luck...jake

 

Well here's the reply I received from Gary Wheeler this morning:

"Tom, we found a rim and center combo that when used together just clears the brakes on the 16" tacomas. The 4runners that were equipped with 16" wheels do have a larger brake setup than the tacomas and while I haven't tried it I don't think they are going to work for the 16" 4runner.

Thanks,
Gary Wheeler"


Good to know. I didn't realize that there were actually differences in brakes between a 16" stock equipped Taco and 16" 4Runner.

 

He got the base model (2001) 4Runner which came with 15's.

And you're right about this off-road forum being a hit! I'm diggin' it. Still not sure everyone has seen it, but hopefully in time, it will become very active.

 

good info mertztr, while at work today i was thinking that a quick look at the part numbers could clear up the "different brakes theory" i however dont have access to part #'s without calling the stealership.......looks like wheelers cleared it up anyway...have fun with your 16's, jake.
btw i like this new off-road section too, thanks whoever made it happen!

 

I wanted 16's specifically for the size tire I run. A 32x11.50r15 would be an inch wider and would give a ton of bulge on my 15 inch rims I had before. With the 16's I end up with the same height of tire but 1 inch narrower. There are a lot more 15" tire sizes available. With 16's you get a shorter sidewall which helps a lot with the bouncy ride. I kept the same sidewall size I had before but got a 1" taller tire and kept my stock ride.

 

So if my 4runner came with the base 15" wheels, and I'm gonna get a set of 16's from somebody else, my brakes are smaller than normal brakes for the 16" wheel? And will that affect my stopping distance at all?

 

Stopping distance is effected by total outside tread diameter. If your diameter increases your stopping distance also increases, just a little though.

 

Weight also affects stopping distance. If you add heavy 33's in place of your stock 235's you'll notice it takes a lot longer to stop.