Could someone explain why a tire almost a half inch narrower and 3/4 of an inch higher than stock is a better off-road tire? I would have thought a wider tire would be better. Also, has anyone tried run-flats (self supporting tires) on their Disco?

 

Anybody?

 

That's the load index and speed rating. 108 means the tire supports a lower weight than the 120, and the Q is the speed rating. Without looking it up, I believe 108 is a little over 2 tons, and 120 is about 2.5 tons, and Q is max speed of 99 mph. I would double check that to confirm. Unless you're running some massive stuff on your truck, I would imagine you could get away with the 108. There might be a 104 available for even less money, I think 104 is spot on 2 tons. I seem to remember the general rule of thumb is start at 104 (2 tons) and go up about 50 lbs for every +1. Its not exact, but close enough. And thats weight per tire. Hope that helps.

 

So, ignoring cost - would there be any disadvantage to the heavier tire? I'm thinking that's the one I should go with in case I'm hauling anything, etc....?

 

Disadvantage- poorer fuel economy. The higher weighted tire will weigh more.

Disco II stock curb weight is 4,543 lbs – 4,895 lbs. Divide that by 4 = 1,135.75 lbs - 1,223.75 lbs per tire. So with a 108Q, you should be able to safely add another 2 tons of stuff to your car (2,205 lbs - 1,223.75 = 981.25 x 4 = 3,925 lbs). Max tow capacity is 1600 lbs, max tongue weight is 450 lbs. So you shouldn never even come close to the 2.5 ton max weight of the 120Q tire. If it were me, I'd run as close to stock as possible, which is 108Q. Unless you have front and rear steel bumpers, roof racks, winch, 200 lbs of tools, 7 people, towing a crane, and 5 cans of gas on the roof, 108Q should be sufficient. But that's just my opinion. The price difference between the 2 shouldn't be more than $15-20 a tire, so go with what you like. It's your Rover, bro. Rock it the way you want.

Remember to get a 5th tire for the spare. Those Wranglers are pretty cool looking, I'd want to show that off on the back of my truck.

 

It all depends on the surface you're running on. The popular thinking is that tall and skinny is better in the snow and gives you better ground clearance, but this is a topic that comes up for debate every once in a while on different forums...

Personally, I like the skinnier tires, but then I'm running a 255/85 16 (33") BFG KM2 on my D2, so I'm biased.