I have to say I was very dissapointed in the life of my BFG's. I don't have an 80 but have run a set on my 40 and 60. The first set I put on, was on my 40 in 2000, I personally thought they were a big improvement over the Eldorado ZR4's my dad always ran and we put on it originally. I put them on after teraing a sidewall rim to tread on the Eldorado's on a peice of limestone. I wanted better sidewall strength. They have performed very well for me in mild mud conditions, snow ice, etc... But after all these years and 35,000 miles, and not many rotations, the rears are slightly more worn than the fronts, but they are done for, I won't run them in the snow at their current state, as they have too little tread left.
Not long after buying BFG's for my 40, I bought a 60, and had to put new tires on it, at the time I liked the BFG's, so I put a set on the 60 too. I got about 40,000 out of them, and they too were about worn out.
What prompted the replacement of the tires on my 60 were bulges in the center of the tread on the rear tires. When I bought the rig, I replaced the tires for this same reason, a bad bulge in the rear tire, that started to leak. The BFG's did the same thing as the tread got nearly worn. they probably had another 5-10K miles left in them, but I got very afraid of a blowout with that kind of bruise in the center of the treads. The tires on my 40 are exibiting the same failure now.
I don't rack crawl, or wheel very hard. I have abused them a few times, but 90% percent of my driving was daily style driving to work. Only difference is I have 5 miles of gravel road one way to work. This tends to eat up tires pretty bad, perhaps it causes the bruises too. Always ran at 40-50 PSI for optimal mileage. Never had any bad crowning wear, even at the high pressure.
These bruises make me question another set on the 40, as I am shopping for tires for it right now. Put some cheap Sport King Radials AT's on the 60, actually been impressed with them. Did very well in a very bad winter for me year before last.
Anyone else see this kind of bruising, I thought maybe the weight of the 60 was the problem, but it is bone stock, no mods, not like a modded 80, how are you guys doing it? Less gravel roads, less pressure, what. Seemed like anything below 40psi makes the sidewalls real bulgey and handling squirmy.