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Discussion Starter · #1 ·
Just like the title says...
I am very interested in peoples opinions/facts on what the best tire pressue is in these?
Best for MPG's?
I know there is endless threads on this subject but when doing a google search I couldn't seem to find a good answer on my tire.
I have the BFG 275/65/20 and i'm pretty sure it's an LT tire. I currently am running 36 psi (1 psi over door jam rating), and find my mpg's lacking. On the other hand comfort is very nice. I have a cold air intake, 18 mufflex, and cortex programmer w/93 tune, I average about 12.5 to 13 mostly city mpg. I don't drive like a maniac nor a grandpa, somewhere in the middle.
Also would increasing the tire pressure help with 0-60 and quarter times or make it more sluggish??
Looking for someone who has a vast knowledge of this subject:smileup:...Please chime in, TX
Eric B.
 

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as a reference, you need to know that PSI is Pounds Per Square Inch
it does not matter if it a wheel barrow tire or a semi truck tire
35 PSI is the same in both

a semi truck is usually 65 or more PSI, because of weight & heat
race cars start with low PSI & pressure builds up after a couple laps at 100+ MPH
desert racers purposely run low PSI for traction

I know that i didn't answer your question, but it gives you a reference point
 

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Discussion Starter · #4 ·
as a reference, you need to know that PSI is Pounds Per Square Inch
it does not matter if it a wheel barrow tire or a semi truck tire
35 PSI is the same in both

a semi truck is usually 65 or more PSI, because of weight & heat
race cars start with low PSI & pressure builds up after a couple laps at 100+ MPH
desert racers purposely run low PSI for traction

I know that i didn't answer your question, but it gives you a reference point
Thanks for the refrence.
Would it be safe to say you are suggesting a higher psi for my truck then the suggested 35 on the door jam ?
I ask this cause of what you said about the semi truck, and lets face it while are trucks aren't semi"s there not prius's either.
More insight would be appreciated, thanks again
Eric B.
 

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Discussion Starter · #5 ·
I had mine at 36psi i just put it to 40 so far so good. Mine r 285-65-20 i got the same tire
This is actually what I was going to try next.
Would you say it is alot harsher now? Any improvement on mpg's?
Does your truck seem to have better pick up due to the increase in pressure?
Tx....
Eric B.
 

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I don't know that there is a hell of a lot you'll be able to do to increase your MPG. I'm running stock tires, at about the same pressure that you have, and I'm getting about the same mileage as you are. I don't think changing the air pressure will make much of a difference, if any (just my opinion and I don't have any scientific data to back it up).

I've just accepted that the HEMI in a large truck that weighs a lil over 3 tons isn't gonna get great mileage. I am usually quite please if I'm close to 13 MPG, I do mostly in town driving with a few short trips on the highway (though I doubt they're enough to matter)

Enjoy your gas guzzling, almost 400 HP beast and accept that we'll never get the mileage of other smaller, less fun to drive vehicles

Exco
 

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Discussion Starter · #7 ·
I called BFGoodrich today and asked them what they recommend, and they said 50 in all 4 corners. Thay said the door jam number is for stock tires only, not for a bigger 10 ply tire, which makes sense to me.
This is what I did and took a short ride and I have no complaints, so will see how I like them in the long run.
I will post back at a future date to let you know abot mpg's and comfort..
Thank you to the people who replied.
Eric B....
 

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50 PSI :Wow1: thats alot for a 1/2 ton. I have the stock badyears and have run them at 40 since I got the truck. You will defianley notice a harsher ride with 10 ply and 50 psi. I would guess that you will wear out the centers long before the outer edges.
 

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Higher the ply RATING, higher the pressure. That is on purpose, as psi factors into load rating. I capitalized rating because that is only what it is, there are not 10 ply's in the tire. The tire doesn't care what truck it's on, it takes what it takes for psi
 

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I ran mine (BFG T/A KO's 285/60/20's) at 50 psi for a long time. Got 17 to 20 mpg avg. which I think is really good for this truck. The wear was even across the tread. No extra wear in the center. I dropped the psi to 40 recently because I could feel the truck seem to loose road contact over small road bumps, etc. . The road contact issue went away after lowering to 40 and the mileage is still the same and ride quality seems to be improved as in softer ride. Doesn't look like it would make that much difference, but it did, or, could just be me. I plan to try 45 psi and see what that does. BTW, my tires are rated to 65 psi max. pressure for towing and hauling. It has always been my experience that max. psi will get maximum tire life (and less rolling resistance which would equate to more mpg) at the sake of ride comfort. Hope this helps you.
 

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Discussion Starter · #11 · (Edited)
Well I did a lot of driving the last day or too and I'm happy to report that I am very happy with the tires at 50 psi, the truck seems to roll better under acceleration with the added pressure and road comfort wasn't really affected, maybe just a tad but nothing big by any means.
Mileage also has impressed me, same driving manners and I'm continually getting 14.2 - 15.5(city) really happy about this .....
Well anyways on to my magnaflow Y pipe and mandrel bent stainless piping install tom. Wish me luck, so long and tx to everyone for there replies...
Eric B.
 

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I ran mine (BFG T/A KO's 285/60/20's) at 50 psi for a long time. Got 17 to 20 mpg avg. which I think is really good for this truck. The wear was even across the tread. No extra wear in the center. I dropped the psi to 40 recently because I could feel the truck seem to loose road contact over small road bumps, etc. . The road contact issue went away after lowering to 40 and the mileage is still the same and ride quality seems to be improved as in softer ride. Doesn't look like it would make that much difference, but it did, or, could just be me. I plan to try 45 psi and see what that does. BTW, my tires are rated to 65 psi max. pressure for towing and hauling. It has always been my experience that max. psi will get maximum tire life (and less rolling resistance which would equate to more mpg) at the sake of ride comfort. Hope this helps you.
I agree with what you say here. You can safely run your tires at the max PSI rating stamped on the sidewall of the tire. This should not cause any abnormal tire wear and is as you say supposed to make your tires last longer. I believe I read somewhere a few years ago when gas prices were at 1.50/liter and everyone was extra concerned about fuel mileage that running at max psi rating in comparison to the suggested psi on the door pillar of your vehicle could increase your fuel mileage by as much as 10% from what you normally get. If you increase your psi by 2-lbs every few days till you reach the max psi for your tire it won't be such a noticeable sudden change in ride quality. This is probably the cheapest and easiest mod you can do to noticeably increase fuel mileage outside of just not driving it at all and that wouldn't be any fun.
 

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was in talking to my service guy yesterday and asked about what tire pressure i should be running if i went with a high ply rated tire and he told me to run it at the same psi as its running now which is at 40psi on the stock tires.
 

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Discussion Starter · #14 ·
Update ..... Dropped the tires to 45 psi 2 days ago and this is where it's def. staying. Better road manners, less hop over bumps , smooth comfortable ride, and mileage is right around 14ish for city driving and that's with being somewhat aggressive with the pedal...
Eric B.
 

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so I'm running those BFG's also (came with truck. Not my prefered choice in tires). I had them set to 45 PSI, well below the posted cold psi recommendations. Watching my air pressure system, they climb to 50 to 52psi on the highway. I can attest the higher pressure sucks for handling and comfort. MPG is better than any truck I've had so I'm happy with that. However, I dropped to 38psi as the Utah heat increases the pressures by 4 to 5 lbs and the #*@& roads play havick with my ride and feels like a tank. I can't see going to 65psi as it says on the sidewall and what some have said here. If anyone has done this also, please let me know your results. Thx
 
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