kidkodiak

I'm trying to understand some of the terminology, and googling it didn't help.

My newest XJ has stock 15x7 rims. I'm going to keep it a DD, on-road only truck for a couple years, since I have an old Cherokee that I off-road in. I've been reading posts about adding 30" tires on stock rims and it seems like it'll work, but I've seen the question come up a couple of times...

the difference between 15x7 and 15x8 rims is what (besides that 1 inch) and why is it called "soft" 8?

Again, I know this is pretty basic but I honestly couldn't find the answer, so I'm hoping y'all here can help clear it up for me.

(BTW, if you can comment on whether the 30x9.5 tires will fit w/o rubbing on a stock height, stock wheel XJ, I'd love to hear that too).

Throttle Jockey

the 30-9.5 will be fine. soft 8 refers to an aftermarket rim. typically black with eight holes in it and the holes are rolled over tothe inside making a "soft" roll over. "soft eight".

BudgetXJ

Soft 8 is a type of steel wheel by Cragar

http://store.summitracing.com/egnsea...5&autoview=sku

kidkodiak

Oh, so it's a specific type of rim only... different than a regular 15x8 rim? Is it that these are recommended a lot more in the threads that I've read because they look better on the Jeeps or something like that?

I wanted to be sure I wasn't missing out on a functional issue that might bite me later if I wasn't aware of it

BudgetXJ

They're common because most ppl like the looks of them and you really can't argue with the price. The main things that you want to consider when you're buying rims is diameter (obviously), width (unless you are going with a tire wider than 12.5", 8" wide is good), and backspacing (distance from wheel mounting surface to back of rim. Stock is 5.25", most guys go with around 4" to make the tires stick out further for stability and to stop rubbing on LCA's while turning with bigger tires)

BudgetXJ

I'm pretty sure you can get away with 30x9.50's on stock rims with stock ride height with very little to no rubbing.

kidkodiak

That's good info. Backspacing is something that's based on the rim selection? Certain rims have different backspacing, is that what you're meaning, or is it something else?

I guess I can probably look that one up, too. It's another one of those concepts I see in every other thread here but never quite grasped. I understand it conceptually (not wanting the tire to rub on the inside of the wheel well and/or against any parts) but wasn't sure how that applied for practicality's sake.

Thanks for taking the time to reply, you guys

BudgetXJ

You can get aftermarket rims in all different backspacings. Less backspacing means your tire sticks out further. Its a fine line though because if you have too much backspacing, you will rub when turning (with 30's you probably won't have an issue), to little and they will stick out too far putting too much stress on the unit bearing/ball joints. Like I said before, I run 4" backspacing and I think its pretty much perfect.

Glad I could help. Don't hesitate to ask questions around here, most of us enjoy helping others and you won't get flamed nearly as much here as you will elsewhere.

northline76

Nope, I had the teraflex 1.5 lift with shackles and coil spacers and I was running 30x9.50s and I was getting some nasty tire rub on road. I also have 15x8 soft 8s on these, but unsure of backspacing.

aircruiser

i had 30x9.5s on my 15x8 soft 8s for about 2 months and couldnt wait to get wider tires. they looked like pizza cutters with the 8" wheel. i would recomend keeping the stock rims if its just a DD i had 30x9.5" muds on the stock 15x7s and didnt rub at all.

you can kind of see how wide the rims are compared to the tires in these pictures





just my 2 cents. im glad i did get the 15x8s tho cause they sit perfect on the 33s now.