Tire Advice

Since the subject of tires never gets old...

I have a 62 CJ5 that's pretty basic. Right now I have a bald set of 33X12.5X15 mud tires that I'm eager to remove. I inherited a new set of 15X8 spoked rims, but my local shop can't tell me what size tire would fit on there, since their computer info doesn't go back 53 years. I'm hoping to just put on something simple and inexpensive. I plan to mostly use the Jeep for ice cream runs into town. I prefer the look of something taller and skinnier, rather than what I have right now.

I guess I'm looking for advice on sizing. Would a 235/75/15 fit on those rims? (I'm clueless about backspacing, etc.)

Thanks for the help!

 

I agree with Glenn - assuming your wheels have the correct backspacing. Not real skinny, but they look good on a CJ5.

I'm curious though. 31x10.50 is about the max on a stock vehicle - has your jeep been modified to accept the 33X12.5X15?

 

If you go to a site like TireRack.com and look at the specs for tires, they will give you a recommended rim width for each size. For example, BFG recommends an 8.5" wide wheel for a 31x10.5R15 KO AT. http://www.tirerack.com/tires/tires...ite Letters&partnum=105R5ATAKORWLV2&tab=Sizes

This is roughly the range in size that you want.

Most of these rims have about 3.5" backspacing. That's about what you want, although a little less (stick out more) would also be ok. You can measure that with a tape and a stick across the wheel - just see how far the wheel mounting surface is from where the bead of the tire contacts the rim. TireRack also has tech pages about various tire and wheel questions - http://www.tirerack.com/wheels/tech/techpage.jsp?techid=101

 

I would look for a different tire shop too, if they can't look at a rim and tell you what tires will fit it. How about 30 seconds with a tape measure or a ruler?

 

I ran 235/75-15 (same as the old LR78-15) for many years on 8" rims and they were fine on my CJ5A.
I used to actually run that same size on 10" wide rims for mainly beach use for soft sand. They worked well, but I had to run radial tubes, mainly to get them mounted. Aired down to 12lbs, they would float on the sand and 4wd often wasn't even needed.
I wouldn't recommend 235/75-15 for the 10", but wouldn't have any reservations for 8" rims.
-Donny

 

235/75/15's will fit on an 8", but that is about the biggest rim you will fit them on. I have an equivalent sized tire on my stock CJ and they look pretty good IMO. I prefer the skinny tire look as well. For backspacing, measure from the inside part of the wheel that mounts to the hub, to the inside edge of the wheel. That is your backspacing. Compare it to the stock backspacing. You should also be able to mount the wheels on the Jeep and see how they sit depth-wise before you buy tires.

 

31 x 10.5 on that rim is ideal, common size so they are easy to find in your favorite flavor.

 

Thanks for the guidance. I haven't followed through with buying new tires, because I've really grown to like the look of the original steel rims. I'm having a hard time finding a used set of steel rims, though. Is there any truth to the rumor I've heard that old Ford rims will fit on my 62? The local scrap yard seems to have plenty of those listed on their site. Thanks again for the help!

 

Ford pickup rims are the right bolt circle, but the center hole is too small. Back in the day, they would cut the centers out of Ford rims to make very wide sand buggy wheels, and then enlarge the center hole to fit over the Jeep hub. These Ford centers tend to crack between the bolt holes and the center hole. The Jeep wheels have a reinforcing lip around the center hole that prevents this cracking.

 

I read that attached older thread and now you guys have me thinking maybe modern radials are a better choice. That Jeep pictured with the Hankooks looks great and I'm a real Hankook fan, both my Tacoma and my wife's Silverado have them and in the winter it's like driving with suction cups on your wheels. So referring back to my thread "wheel dilemma" what size radial will fit best on my 4-1/2" wide 16" wheels? Another member here came to my rescue with another 4-1/2 so now I don't have to mess with that 5" wheel except as a spare.

 

I think your teasing me, what's the rest of the equation? 215???R16??? I never have comprehended these metric crap tire sizes. My old Chevy has 10.00x16.5 that tells you what it really is. The old tires I took off these Jeep wheels are 6.00x16, that I understand. Is there any problem putting radials on steel wheels built for tubed bias ply? I'm so confused!

 

If you have 4-1/2" x 16 " Kelsey Hayes wheels you can run tubeless radials IF the rims are tight.
That means no leaks at the rivots where the rim meets the disk.
Do not run anything other than the narrowest / tall radial that is available.
That implies the 215 85 R 16 size preferably with 6 ply rating.

 

Tubes for radials? I never heard of that before, what will they think of next? cell phones?

 

They will fit fine on those rims. I put 245/60/15's on 7" rims and they worked fine. I think that was the largest tire that was good for that rim. Since your tires are smaller in width, they will be ok on those rims. The big issue is how much clearance do you have between tires and suspension parts/wheel well parts, etc., when you are fully cranked one end to the other?

 

I have some 15x8 spoke wheels with Armstrong 33x11.5's on them. Tires seem a hair too wide IMHO. The rims and tires are on the side of the house, I'll snap a picture when I can for you to see for yourself.