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Overkill... Is just about the right level of performance. The proper level of engineering is over-engineered for the job at hand. Only the bean counters want to run everything to within 10% of the failure limit, as a means of trading longevity for cost savings. Witness the Badyear Blowout 500s that were installed stock on our CRDs.
Think about it this way: You are moving furniture out of your house. Do you want to hire the "average joe" who might be able to do the job, but will be worn out by the end... Or the local strongman who will barely break a sweat lifting your couch? Yea, thats what I thought.
Our CRDs weigh in at 4300 lbs. The ratings of the "stock" tires are somewhere around 1900 lbs each. That SEEMS like an OK number, since you only expect the tire to hold 1/4 of the weight, right?
Wrong.
The weight of the car is constantly moving. It is only equal at 1/4 per tire when the car isn't moving. In motion, it is a "live load" and at varying points, a single tire might be asked to hold up to 75% of the weight of the vehicle! You get to that 75% number if you happen to be turning and braking at the same time, which will heavily load the front wheels (braking) and the one wheel on the outside of the turn. In braking straight, both front wheels can have force that easily exceeds the full weight of the vehicle, because they have inertial weight as well. In vertical lift situations, this would be considered a "shock load" that can impart onto the lifting cable as much as double the weight of the lifted load whenever it starts moving (upwards) or stops moving (downwards). The forces are the same for horizontal motion, but starting off is less of a shock load on the tires than stopping can be.
So I will ask the question again... Do you want your tires to be that close to their operational safety limit? 1900 lb limit, 1075 static load when sitting still. Sounds ok, right? 75% of vehicle weight on one wheel... 3225= 1.7 times the max tire load weight in an extreme cornering move. Will the tire fail? Impossible to predict, but I wouldn't want to be in that vehicle. How about a panic stop? You don't do those for fun... 4300lbs, but with as much as 4300 additional from inertia. 75% of your stopping force is in the front 2 wheels, so they are carrying 6450 lbs, or 3225 again. See the problem here? Realistically, the tires will probably hold, or we would have been hearing about tire failures in panic stop situations in the news already. What IS happening is that the tire will severely deform its sidewall in such an extreme move, and possibly cause internal damage that may only reveal itself later.
I for one, like to increase the safety margin by increasing the strength of my wheels. They are ALL that is keeping you and your family safe. When you need that margin... You will really NEED it.
As for my experiences with the BFG commercial tires - I like them a lot. I'm very happy with the Traction style (LRD) so far for daily driving. On the highway tread version (LRE) that I had before, I got 60k miles from the front ones. I'm expecting better from the tractions, b/c they have 2/32 more tread depth. Interesting observation tho: They are all the same size, 215/85/16... And the traction LOOK wider than the highway tread by a decent amount... BUT, there was a set of Goodyear LT 215/85/16 in the shop the day that I got the tractions. Those looked like pizza wheels next to the traction, I coulda sworn they were only 60% of the width of the BFG yet had the same size rating? Weirdness.
_________________ Proud supporting vendor of LOST Jeeps TRAVELING CRD TECH. I come to you! Need help? Just ask! I've taken it apart more than most. Email jeep [at] maincomputer [dot] com - BOARD MESSAGING IS BROKEN Over 225 CRDs currently driving with my valves, timing belt, rockers, or ARP Studs. Bad noises = REALLY bad things.
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