It is time to get some new Nike's for the Disco. I've been reading a lot of threads regarding tire size. However, I am overwhelmed by so many different sizes that was mentioned.

So here is the deal, I am looking at the OME 2" suspension kit from Lucky 8. That would give me more room to play with in regards to sizing. Take note, I do not off road. (The nearest trail is a 4 hour drive or to another state) So you might ask, why am I getting a lift and bigger tires that will eventually hurt my mpg? I don't know, maybe I've been brain washed by all these good looking Disco's on this forum.

Anyways, what is thesafest tire size for 18" without harming the drive shaft, rear/front differentials, and brake lines?

I've been following lipadj46's thread pretty closely. The choice of tire really depends on the size as not all brands offer the same size.

 

Unless you are getting extreme you dont need to worry about a larger tire size doing any damage to your truck.
As a general rule you can plus size by 2 with little to no problems.
Problems being tire rubbing when going over bumps or turning the steering wheel to full lock.
So a taller tire will rub the fenders when going over bumps, a fatter tire will rub when you turn to full lock.
A taller and fatter tire will do both.
If you go to www.tirerack.com you can see what sizes will fit with no problem.
And remember that a more agressive tire will have a deeper tread and thus be taller yet.
Tire size does not include the tread depth.
Confused yet?

 

Your options in 18" are very limited, but there are still some good options. Keep in mind that if you go up in size you really ought to replace all 5 tires and then rotate through your spare as well to prolong life.

At the risk of sounding like a company mouthpiece, I will again reiterate how pleased I have been with the Hankook tires. And, for the money, WOW what a tire! I'm sure you saw my contribution in the other thread, so I won't bother re-posting the link and pics, but you really ought to give them serious consideration. I do a lot of on-road driving in my truck too, and these tires do fine without humming or vibration.

 

First of all, if you haven't rebuilt/replaced that front drive shaft, that is the first thing on your list with no exception.
Don't get too crazy with tire sizes, stay with a good all weather tread and stay below a 265'18 tire size or you'll loose 1.5 MPG.

 

Rotating the spare tire with the others is not needed.
You are better off just leaving it on the back of the truck and then it will last forever too.
So the next time you need tires you will only need to buy 4.
Rotating the is old school bias ply tire teaching.

 

I say dont get a lift since you dont off road, and go with some General Grabber A/T2's for that rugged look. 265/70 r18 will fill out your wheel area just fine and you wont need to make any mods and spend money on something we really wont benefit from.

 

Rotating the spare with the others is not needed, but if you change the size on the ground it's best to have a spare to match (for obvious reasons). Plus, if you rotate all 5 tires you'll get 20% longer life/use from them before you have to buy tires again.

Leaving it on the back of the truck to "last forever" usually means it gets forgotten, dried out, low pressure, seized bolts, etc. If you rotate it through it's hitting the ground every 5k-6k miles and you eliminate the possibility of the aforementioned issues.

Just my .02

 

If on a budget and if your old tires are in decent shape (and close in size) just keep the best one as your spare and spend the extra on the 4 tires. My truck has a bad front end so my front tires met an untimely death (I was lazy with my rotation schedule). My back tires are in decent shape so decided to keep the old rear as the spare and be able to buy a better driving tire. A proper rotation schedule is key and using a spare in the rotation is obviously better but I would rather have a better set of four than a lesser set of 5.

 

Disco Mike, I think I'm passed that stage in Disco life... I got the TW remember.

--Thanks everyone for your information

Bryce, I really like your set-up with the DynaPro AT'M RF10, also the price is very tempting.

It really hard to believe that the 265/65/18 DynaPro AT'M RF10 is lower in price than the 255/55/18 Nitto Terra Grappler.

So 265/65/18 it is!

 

Don't worry about larger tires rubbing when you turn. It's super easy to adjust the steering stops, at least it is on a D1. There is a bolt in the steering knuckle that hits on the axle to stop the wheel from turning any further. My buddy helped me adjust mine today and it makes a huge difference. It's awesome to be able to turn and not hear the tires rubbing the trailing arms.

Even if you don't off road the Disco just looks cool sitting a little higher. I had mine nose to nose with a stock 99 D1 today and the little extra height made a huge difference. The 99 looked like a soccer mom mobile next to mine.