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35 is pretty low, way to low for suggesting on 7500 lb + CC empty.
The rear will be floating around unless it’s a single cab truck 5,000-5500 lb truck.
That’s what I run in my Yukon Denali on all 4 corners.
That’s also what my son runs on his single cab GMC Sierra 1500 5.2 gasser.
My front axel weighs about 4400. Rear weighs around 2800. I am running stock tier pressures in the front fro 285/79/17 at 42psi. (Stock is 245/75/16 @ 55psi)

Rear stock is 245/75/16 @ 80 psi. With my new setup with 285/70/17, I can run 60 psi and it will be the equivalent to stock. At 35psi each tire can hold 2105lbs. So I am good at that psi empty. Even with a fill cab and some stuff in the back I will be ok.
 

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Even at those pressures my tires still wore more in the center due to a little over inflation.......



And to the guys I gave the air pressures to....... If you make the adjustments to you air pressure, "feel the truck out" before you start doing any quick maneuvers and turning. With the new psi in the tires the truck will act/react differently.
 

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Ok so 265/60/20 on the front at 60 psi can hold 2660 lbs for each front tire. If you run 52 psi on the 285/60/20 the front tires it can hold 2670lbs. So you can run 52psi in the front and you will be good.

Rear..... 265/60/20 at 75psi can hold 3110lbs in each tire. On the 285/60/20 at 61psi it can hold 3125lbs. So when loaded you can run that. But you might bump up the pressure to give you more stability. (applies to front tires too) Empty you can run 40 psi (2000lbs) or 45psi (2175lbs) this is just advice and I take no responsibility for what psi you run in your tires. This is from my calculations from the load inflation chart.

Personally I run 42 front 35 rear in my tires. I have 285/70/17E


Ok thanks for looking into that.

So DISCOUNT TIRE set all four tires to 60 PSI. I've been running that since late December. I'm averaging about 11 miles per gallon and even with the bigger tires over the stock ones, I have not lost any miles per gallon which I thought I would.

Wouldn't decreasing the air pressure make my miles per gallon come down? I think the truck rides fine with 60 PSI in all four tires. However the one thing I don't want to do is run the tread down prematurely by being at the wrong pressure. I guess it's all not about Ride comfort but also the correct psi so the tires wear evenly.

So from your post above you're basically saying come down in the front from 60 to 52 and go up 1 psi in the rear from 60 to 61?
 

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Ok thanks for looking into that.

So DISCOUNT TIRE set all four tires to 60 PSI. I've been running that since late December. I'm averaging about 11 miles per gallon and even with the bigger tires over the stock ones, I have not lost any miles per gallon which I thought I would.

Wouldn't decreasing the air pressure make my miles per gallon come down? I think the truck rides fine with 60 PSI in all four tires. However the one thing I don't want to do is run the tread down prematurely by being at the wrong pressure. I guess it's all not about Ride comfort but also the correct psi so the tires wear evenly.

So from your post above you're basically saying come down in the front from 60 to 52 and go up 1 psi in the rear from 60 to 61?
Your right. Lower psi with lead to lower mpgs. It's give and take. You can't get better tread wear and better comfort (ride) and run higher psi in the tires. Its up to you what you want to do. You likely won't see funny tire tread wear untill it is too late to correct. Even running the suggested PSI I gave you, the center might still wear out a littler quicker. But it will be at a slower rate than higher PSI in the tires.

Run 52 psi front and 40/45 PSI rear Empty not towing or carrying a heavy load. It would be better to weigh the rear of your truck to get a better idea of how much you can carry in the bed running 40/45 PSI rear.

If you are going to tow. You can run 52PSI in front. You can bump it up a couple psi to give you more turning staibility. In the rear you can run 61PSI. Again for better staibility and hwy speed maneuvering you can run a couple more PSI in the rear. Go to the load inflation chart I posted, find your new tire size and see the load you can carry at the PSI I recommend and you will see it is the equivalent to your stock tire size at the stock psi on the door.

You should not see a drastic mpg drop coming down 8 psi in the front and the rear staying about the same.

Do what you feel is right. This is your truck and sometimes you can't have it all. It's a game of give and take with tires. And again ........ If you make the PSI adjustment take it easy. Your truck will act and react differently depending on how much PSI you take out of your tires.......

I am not telling what to do and will not take any responsibility on the suggestions I have made to anyone in this thread. The suggestions I have made are calculations based off of nittos load inflation chart.

On my personal truck that I daily drive and take my family on trips with, I run 42 front and 35 rear based off of the calculations from the load inflation chart. If I carry a heavy load or will be towing I adjust the tire PSI accordingly. My tire size is LT 285/70/17 Load E1 with a 121Q load index
 

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Your right. Lower psi with lead to lower mpgs. It's give and take. You can't get better tread wear and better comfort (ride) and run higher psi in the tires. Its up to you what you want to do. You likely won't see funny tire tread wear untill it is too late to correct. Even running the suggested PSI I gave you, the center might still wear out a littler quicker. But it will be at a slower rate than higher PSI in the tires.

Run 52 psi front and 40/45 PSI rear Empty not towing or carrying a heavy load. It would be better to weigh the rear of your truck to get a better idea of how much you can carry in the bed running 40/45 PSI rear.

If you are going to tow. You can run 52PSI in front. You can bump it up a couple psi to give you more turning staibility. In the rear you can run 61PSI. Again for better staibility and hwy speed maneuvering you can run a couple more PSI in the rear. Go to the load inflation chart I posted, find your new tire size and see the load you can carry at the PSI I recommend and you will see it is the equivalent to your stock tire size at the stock psi on the door.

You should not see a drastic mpg drop coming down 8 psi in the front and the rear staying about the same.

Do what you feel is right. This is your truck and sometimes you can't have it all. It's a game of give and take with tires. And again ........ If you make the PSI adjustment take it easy. Your truck will act and react differently depending on how much PSI you take out of your tires.......

I am not telling what to do and will not take any responsibility on the suggestions I have made to anyone in this thread. The suggestions I have made are calculations based off of nittos load inflation chart.

On my personal truck that I daily drive and take my family on trips with, I run 42 front and 35 rear based off of the calculations from the load inflation chart. If I carry a heavy load or will be towing I adjust the tire PSI accordingly. My tire size is LT 285/70/17 Load E1 with a 121Q load index


OK I'll give 52 PSI in the front with 45 in the rear empty to see how it rides. I think this would be fine for the winter but I also run a part-time landscaping business getting ready to start in about two weeks through mid-November. I'm thinking maybe just keep it at the 52 front 61 rear for daily driving and towing that maintenance trailer. Would be just too much airing up and down the rear from 45 to 61.

I'd be airing up and airing down like a dozen times a week due to the fact I tow a 12 foot single axle maintenance trailer. I'd say probably weighs around 2000 pounds with my mowers and the weight of the trailer combined. Maybe a few hundred more depending on what equipment I have on there.

I also tow a dump trailer from time to time and when that thing is loaded it can be anywhere between 6000 pounds to over 12,500 pounds. I would imagine for the rears I would want to be at the full 80 psi max on the tire sidewall with that big trailer don't you think? What about the front psi towing that big trailer?
 

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OK I'll give 52 PSI in the front with 45 in the rear empty to see how it rides. I think this would be fine for the winter but I also run a part-time landscaping business getting ready to start in about two weeks through mid-November. I'm thinking maybe just keep it at the 52 front 61 rear for daily driving and towing that maintenance trailer. Would be just too much airing up and down the rear from 45 to 61.

I'd be airing up and airing down like a dozen times a week due to the fact I tow a 12 foot single axle maintenance trailer. I'd say probably weighs around 2000 pounds with my mowers and the weight of the trailer combined. Maybe a few hundred more depending on what equipment I have on there.

I also tow a dump trailer from time to time and when that thing is loaded it can be anywhere between 6000 pounds to over 12,500 pounds. I would imagine for the rears I would want to be at the full 80 psi max on the tire sidewall with that big trailer don't you think? What about the front psi towing that big trailer?
Good call.


As far as going to 80 psi you can but at 61 psi on the new tires you will be fine too. 61 on the new tires are the equivalent to 75psi on your stock tires. But it's up to you. You will get better stability with more psi. You better have a good compressor to get 80 psi in them tires. Lol

I have a 130psi 20 gallon compressor and when it's full and I am filling my spare tire to 60/65psi it is crying.
 

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Good call.


As far as going to 80 psi you can but at 61 psi on the new tires you will be fine too. 61 on the new tires are the equivalent to 75psi on your stock tires. But it's up to you. You will get better stability with more psi. You better have a good compressor to get 80 psi in them tires. Lol

I have a 130psi 20 gallon compressor and when it's full and I am filling my spare tire to 60/65psi it is crying.


OK I'm going to give it a shot and see. As far as towing that dump trailer, I might just put close to 80 on the rears because that thing is just so heavy it makes me nervous. What did you say you were put in the front tires one telling that dump trailer? Maybe up to 60?
 

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OK I'm going to give it a shot and see. As far as towing that dump trailer, I might just put close to 80 on the rears because that thing is just so heavy it makes me nervous. What did you say you were put in the front tires one telling that dump trailer? Maybe up to 60?
You will be fine with 52psi. But would not hurt to go higher. 55/60 is ok too.
 

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IMO and many others when towing especially heavy bump the fronts up to at least around 65 front and 75-80 rears.

All I can suggest is to try what you want and what you think is right and go from there.
It’s only the cost of another set of tires sooner than later if you the lower psi doesn’t work out as you hoped.

Fronts 55 is only for the ride when empty, 60 is good but you’ll have a little more stiffer ride.
Overtime you’ll see that the front floats around a little at 52 when empty and the outside tread will wear a little faster than the middle.

A real good suggestion, pick up a tread depth gauge, there only a couple of bucks.
Check the tread depth across the tread about every couple hundred miles.
Then you’ll know what PSI works the best.
https://m.tirerack.com/tires/tiretech/techpage.jsp?techid=148
“Good Luck”
 
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