By Tony Konovaloff
Its time to buy new tires and I thought you might like to hear what I am thinking while I look. This is just about all my options. First and foremost is just what I am putting the tires on. I drive a BJ 60 with a 5 speed running through 4.88 gears in the axles. The gears will allow me to run taller tires. But not too tall. Without moving the axles to the other side of the springs, I am limiting myself to 33 or 34’s. I have heard of people running taller tires but I just don’t think it would be practical on my rig. Another thing I like is that 33’s and the gears I run put the speedometer just about right on.
While I would like a wider tire at times there are some drawbacks. The whole steering system was engineered with a 6 inch rim with a 3.5″ backset holding on the tire. Adding to this has to be done to the outside due to clearance issues. Widening the rim to the inside would cause some unacceptable rubbing in turns. But adding to the outside adds a lot of leverage on the kingpins. This is what causes the wandering on the highway that you sometimes experience with wide tires. I once let Eric drive my 62 with skinny tires and he was surprised how well it steered. He runs a much wider tire than I do. So I think the best I can do is add to the width of the tire but not the rim, probably 10.50’s. I had a set before but shorter in height than I currently run. And this width is not too tough to turn with my manual steering either. And just in case you think skinny tires can’t go hardcore wheeling, I ran 33 9.50’s all the way through Rubicon and didn’t have a single issue that was tire related.
AT’s or Mud Tires? I have always been a fan of all terrrain tires because I drive my rig to work each day. While my BFG A/Ts have worked great in everything from rocks to wet snow, there is one place they are useless, in mud they turn to slicks. So now I have become a believer in a more aggresive tire after not making it up a muddy hill in Oregon this summer. Enough is enough.
-New Shoes for the Diesel-
Finally came up with the money and made a decision about my tires. I decided to go with 33 10.50 15 BFGoodrich KM2’s. I was leaning to these tires for a long time and then Eric beat me to the punch and sent pictures of Lilly with my choosen size tire. The straw that broke the camels back was now tossed into the wagon! I chose to go a little wider than the 9.50’s currently on my rig, but I stayed with 33’s. Running taller tires without a springover on a wagon just isn’t very practical and like I have said before I don’t like tippy.
So far so good. Being that I just put them on not alot of real world advice to offer. Bit of a surprise that they don’t make much noise, not that you could hear it above the noise of my diesel anyway. I did open the window while coasting downhill on the highway and listen for some tire noise but I can’t say there was much at all.
The biggest improvement so far is the fact that I can run much lower air pressure in this width. I can’t believe how much softer the ride is, 35psi versus 45psi makes a world of difference in ride quality. And the ability to air down is going to be interesting as well. With my 9.50’s I couldn’t let out more than about 10psi without the side walls starting to hit the ground, not a good idea. Eric has already had his down to 20psi and says they work great at that pressure.
The extra width seems to have had no impact on steering effort, something to consider with the manual steering box in my rig. A plus to the bit of extra width is that the hubs now have some additional protection when crawling around in the rocks. Before, both front and rear hubs protruded past the side walls. I once broke 3 hub studs on a rock.
Can’t wait to get these things dirty.
