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Discussion Starter · #1 ·
I am hearing mixed input on this issue. The door states 65psi but the tires say max load 80psi. What is the best to run considering tire wear and fuel economy.
 

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I run what the tire says.
 

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I wouldn't run 80psi! Dodge engineers have determined that 65psi will get you the best all-around performance (handling, ride, tire wear, reliability). You can bump it up a few psi for a little better mileage but you will alter most of the things i listed (in a neg way)...
 

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Discussion Starter · #4 ·
well right now I have the rears at 66 and the front at 70lbs, I wonder if I'm about right?
 

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Run 65 all around. The only reason that the tires say 80 psi max is for the fact that they are load tires. If you have a heavy load, you can run up-to 80 psi to keep from squating. They will wear unevenly if you run them max all the time.
 

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it all depends on the tires and how they are engineered on how much air pressure they should run and no one tire is the same exact thing. I run 80 in my goodyear wranglers which is what goodyear recommends but it all depends on your situation and tires my factories i ran 70-75
 

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Discussion Starter · #7 ·
so alot of different people are doing different things. Now doesn't under inflation hurt gas mileage?
 

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cut it down the middle if your unsure...73lbs
 

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Having your tires inflated over what the door said may cause ride issues because you are on a firmer tire. I run mine higher because i never know when i am gonna put a heavy load on and i dont like soft tires for towing.
 

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Discussion Starter · #10 ·
Well most of the time I have a cab over camper on the truck so carrying around 2500lbs in the box sounds like a good reason to keep them aired up :)
 

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I run mine what the second door decal reads for unloaded weight
I think 45 in the rear and 65 in the front
I towed a extended cab 1997 4x4 5.9 truck today with these pressures and it was fine
i like the soft ride on the street since this is mostly used as a daily driver
 

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Discussion Starter · #12 ·
but won't that hurt your fuel mileage?
 

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It may slightly but I like the smooth ride it gives me. The mpg is so bad I dont think it it will matter much
it's a day and night difference of the ride quality from 65-45
the reason I purchased my DRW is becuase it had a better ride than the SrW
i did not realize why until I found the door pressure decal that the psi was set lower from the factory and that was why the DRW trucks had a smoother less jaring ride over the SRW
 

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Discussion Starter · #14 ·
we basically have the same truck so I will try what you say. Just trying to get this mileage up and hopefully as it breaks in it will help.
 

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I find 55 in the rear and 60 in front gives a good ride and doesn't effect mileage. I use the tire pressure chart from Toyo and or Dodge and inflate according to the weight/inflation ratio.
If driving the freeways above 65 I inflate the fronts to 65,but leave the rears alone. Thin is carrying a cabover camper full time- been doing it for years.
 

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I would not lower the pressure in the front lower than what it reads on that decal
that Cummins engine is very heavy. If I were to tow more than 10k I would up the pressure in the rear. the most I pulled is 10k and it does fine. I was a bit nervous yesterday towing that CTD at 40--45 in the rear tires but once I got going I did not feel a need to pull over and raise the psi.
I am about to hit 10,000 miles and the best I have seen at these pressures is about 20 mpg on country roads. I got about 11 mpg towing 10k yesterday
 

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I just read the decal it's 40 in the rear and 65 in the front for light loads
which is 2 passengers and no more than 200 lbs in the bed

heavy load is 65 front and rear
 

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65 in the front, 40 in the rear for no load runs, any more in the rear and your tires will wear out in the middle, too much floatation on a dually with no load in the box. trust me, figured this out after two sets of tires. :$:
 

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Discussion Starter · #19 ·
so most of you run 40 rear, 65 front?
 

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I run 65psi in both the front and the rear all the time. The only reason I don't run more than 65psi is because it rides like crap as it is.
 
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