Moderator: volvite
I don't think you would, at least on road, since the air pressure is what holds the vehicle up. The load a tire can handle is a function of the pressure it can hold and an LT tire will need a higher pressure to have the same load capacity as a P. The design just allows higher max pressures so higher overall load bearing capacity with the LT, but underinflated they will overheat. I have no idea what difference the rim makes though - do rims have pressure limits? I've always assumed they were all equally air tight if the tire was within specs to fit on it. Am I wrong about that?mikecfry wrote:That makes since considering it looks like you are running much larger tires, you'd inherently run a lower PSI.
55psi? Really? You will be hating life super fast. The most I go with mine is about 42psi, and that is a very firm ride. If you want to be completely anal about the whole thing, go to the BFG site and find their load ratings chart for your KO. You will find that 55psi will be overkill. I can't believe someone from BFG actually told you to do that. Crazy.mikecfry wrote: "Your original equipment tires are designed to carry 2337 lbs. per wheel at 35-psi. Mike, you are absolutely correct; your new All-Terrain T/A KO tires must carry the same weight; so to carry that weight, please increase the pressure to 55-psi on all four wheel positions."
It's probably safe to say that most if not all of us are out of warranty. Although, I recently had my exhaust manifold replaced under warranty (emissions, 8 year/80k) and no questions were asked, only compliments given. As always, it depends on the shop and the modification associated with the repair needed. Even though I have some aftermarket exhaust, the manifold was still warranted and replaced free of charge.mikecfry wrote:Actually I have to say at 55 PSI it hasn't been the least bit rough. I did take the time to research the load tables myself last week to be sure, and found that the OE P265/65R17 tires are rated for 2,337 pounds at 35 PSI. The new LT265/65R17 are rated for 2,270 at 50 PSI and 2,420 at 55 PSI. So in reality the inflation should be something like 53 but that's splitting hairs. By comparison, if the size increases to LT285/70R17 then you only need 40 PSI to carry 2,315 pounds.
When I had LT285/75R16 on my Jeep I only ran about 34 PSI and that was with a 150lb steel bumper and 100 lb winch, but the smaller tires just need more pressure to get the right amount of air to hold the weight. Seems like there are not a lot of folks here sticking with the OE tire size? Have you ever had any warranty issues with modifications?