Alright so it looks like I am finally going to get some General Grabbers A/T2's. But I need some guidence on what size I should get. I want to get the biggest size possible, without rubbing obviously. I searched and all I could find was the max size for 16" wheels, and I have 18"s. Here are the tire sizes offered:

265/70R18
275/65R18
255/60R18
255/55R18

By the way, I have stock suspension, no lift or anything.
Thanks for any help!

Cameron

 

A couple of thoughts, first you really need a lift to prevent tire rubbing. Second, do you really want to loose a couple MPG with going to a max. size tire?

 

I am planning on a lift in the future but for now I am going to stick with what I have. As for the tire size, what ever you think will preform best off and on road is fine. I dont want to loose MPG if I can help it, but I dont mind a small drop. If I can avoid the rub I would prefer that, so not going to the full max is fine with me. SO i guess the question is, what is the max I can do without rubbing?

 

Cam' from the sizes you put here the only ones that will fit (other than stock size) are the 255/60R18's. The others will rub. If I were you I'd seriously contemplate these tires. http://www.tirerack.com/tires/Sizes....TR+Sport+H%2FP Beleive it or not Sumitomo makes most of the high end Dunlops, and Goodyears. (I mean track tires for performance cars). I have had three sets of them on my Audi ($98 each), I have also had RE05's ($310 each) and many other tires that are supposed to be the best, and cost a ton. I have to say the Sumi's out lasted, handled, and were quieter than all of the Ultra performance tires I tried.

I can't speak for these yet (ordering them) but if the happiness I had with the street tires is half for these, they would still be great.

Just my $.02

 

You are putting the cart in front of the horse.
18's don't work well off road in the first place, large tires don't work, even on a D2 without a lift and you stand to loose 2 MPG pretty easily.

 

Yeah I've been told that, but for now I am not doing anything that serious. Just fun easy stuff that I can do on the weekend, and the occansional mud. it sounds like 255/60R18's will be the best choice right now. For me, I like to explore, not climb. I drove through a river and up some huge wet hills with horrible toyos tire without a problem, minor spinning.(there is 35$ tread left). I think for what I do, just a tire upgrade will be perfect. The only place i had trouble was in some mud, and even that couldnt stop the disco, once again just a bunch of spinning, but i worked the wheel to get out! I think grabbers will solve that problem hands down. Agree?

 

Even with a somewhat sagging suspension you should have no trouble with a 30" tire (ie the 255/60R18) Stock is a 29" tire and going with a tire only 1" larger in diameter, means it is only 1/2" taller as far as wheelwell clearance issues are concerned. You will absolutely not rub a 30" on the street, in fact, you're likely to only even come close to rubbing those in a very fully twisted up situation, which based on what you describe you're looking to do doesn't seem likely.

I'm a BFG guy and I'd point you at BFG AT's but the price is right on those Grabbers and the tread looks really similar to the BFG AT. Personally, I don't think you can go wrong with that tire/size combo you've selected if you want to keep your 18" rims. The difference in overall size is so small, that as far as the drivetrain is concerned it is practically the difference between new and old tires of the factory spec size. Any fuel consumption changes will be negligible and if you do much freeway driving, if anything, you'll actually see a tiny increase in fuel economy. In fact, it isn't even enough to require a speedo calibration gear.

So that answers the tire selection question, but that leaves the four wheeling technique issue. When it comes to mud there are essentially two totally different schools of thought. Some people like narrower tires and like to leave them inflated, the theory is that they will cut through to the bottom of the goop where there is solid ground. Another school of thought is that you want larger, wider tires that are aired down so you can ride on top. In both cases you want tires that have good lug clearance as the issue with tires and mud is that the mud fills the gaps in the tire and you're more or less on a slick, that's why mud terrain tires have big voids. In my experience what has worked best for me is to treat mud like sand, bigger tires that are aired down fairly low. Then again, off road, you should be aired down already anyways.

Which is why/how you'll learn about why a larger rim is not necc a good thing offroad. Off road you want the exact opposite of what you want on the street, you want more sidewall. More sidewall lets you air down more while still having a good amount of rim over ground height and even when not fully aired down, gives rocks/roots/etc cushion room when tire contact is made. Larger rims provide better on road stability, but off road limit how much you can air down, provide a stiffer ride with less cushion for impact and they also become a rock magnet increasing the likelihood of sidewall pinch. True, 17"s are not uncommon, but generally you're up into 35"+ tire sizes before you see those come out.

So now that you know that, you might consider replacing your rims along with your tires so that you can go to a 15" or 16" rim, which will perform better offroad. That is, if you want to enhance offroad performance, with a slight handling impact to your street driving. Just something to consider

 

Thanks man that was a good write up!