Another M813 question

[cbvet]

Okay, I brought the M813A1 home. Wow! What a difference from the Deuce. I LOVE the power steering.
With the 1400 tires, it really sits high. Ran just fine, about 60 miles. Seems to want to run 60 mph.
Question: Air pressure in the 1400 x 20 tires. Tires say 100 psi max. What would you run for primarily highway use, lightly loaded?
Thanks guys,
Eric
CBVET

 

[alphadeltaromeo]

See, this is the ONLY reason I don't like SS...when I read posts like this one, it makes me desire that which isn't mine

 

[cbvet]

Kinda like Playboy online, huh?
Seriously, I never would have expected to find a truck like this for the price I paid. I can no longer say "How come I never get in on a deal like that?"
Eric
CBVET

 

[alphadeltaromeo]

Well, I don't know what kinda deal you got, but yanno, I'm happy for you! To have a new toy...well done bud...now change your signature line to indicate it hehe

 

[DDoyle]

Tire pressue should be on the data plate on the dashboard.

Congrats on your new toy.

DD

 

[cbvet]

Tire pressure on the data plate says 80 front, 50 rear. I suspect that is for the 1100 x 20 tires.
This truck has the 1400 singles on it.
One guy I've talked to says he thought they only ran 40 - 50 - lbs in the 1400s.
I guess I'll have to try to find a TM with the info.
Eric
CBVET

 

[TheBuggyman]

I run 70 psi in mine, loaded and unloaded. Is it right? Dunno, but it works very well in both instances and I do not have to keep changing the pressure!

 

[cbvet]

Looked at the TM. It says 50 front & 30 rear! The sidewalls bulge a bit at that pressure, but maybe that's typical?
Eric
CBVET

 

[halftrack]

Unless you want to be going through tires relatively quick, use the Max pis posted on the tires. It will tell you what the pressure should be for duals and singles.

 

[steelsoldiers]

My 923A2 weighed about the same as your 813A1 and the manual specifies 70 psi front and rear for the 14R20's. Of course the CTIS system only took them to 60 psi, so for long distance highway driving I was supposed to disable the CTIS and manually inflate the tires to 70 psi. I ran to Aberdeen and back with 60 psi in the XL's and they never felt hot to the touch nor did they show any unusual wear.

 

[cbvet]

Thanks for the info, guys!
Eric
CBVET

 

[BassnTruck]

Unless you want to be going through tires relatively quick, use the Max pis posted on the tires. It will tell you what the pressure should be for duals and singles.

Sorry but this is wrong. The MAX PSI is for when you have the MAX weight on each tire. For Ex. Say each rear tire is rated for 2000lbs and you have duals on each axle. So that gives a total load capicity of 16k lbs . OK So if you have a total of 16k on the rear axles and the tires say 80 PSI Max then in this case you need to put 80 PSI in them.

Otherwise you will wear the centers out of your tires in a very quick manor. You need to find out what the maker of the truck recommends for tire pressure at your rated load. Say empty. Most are half what the MAX PSI is if you need a generic answer.

Being most do not drive their trucks on road at high speeds for long distances the wear will not be as noticable.

But your tire wear and mileage will tell you just where you need to set them if you learn and watch them.

Higher pressure will net you more MPG (less surface area touching the ground) but it will in turn eat your tires. Each truck has its own happy medium you just have to find it.


And for a prime example.

I loaned my brother my 2500 Ram CTD over the winter last year to drive since he needed a car and couldn't afford one. Its E range tires are 80PSI Max. Well being the idiot my brother is trying to help he actally checked the PSI in the tires one day at the fuel station. (I am stunned he even did this.) But anyway they were at 35 front 40 rear. He then filled them all up to 80. I got the truck back this summer in July (After I bought him a Jeep Cherokee because he kept damaging my truck) to find out all 4 tires were bald in the center after the 3500 miles he put on it. So it now has new tires.

And FYI that winter he managed to make me get a new windsheild, New hood, New hinges, and took out a 35' light pole on the side of the street with my cow killer front bumper. If that bumper was not on there I would have lost the truck. I have still yet to fix the bumper and replace the broken headlight buckets.

Sigh


If any of you ever meet my brother. Don't loan him something with wheels.

 

[Cdub]

On my M925a1, the side of the truck says 55 PSI and I try to run around 60 PSI which feels good for the ride. These tire will throw you a little if they have to much PSI when you hit a bump or bridge joint...

........the manual says

 

[cbvet]

It's looking like I should run 60 - 70 lbs all around & see how it does.
Thanks again for all the help.
Eric
CBVET

 

[DaveP]

Unless you want to be going through tires relatively quick, use the Max pis posted on the tires. It will tell you what the pressure should be for duals and singles.

Sorry but this is wrong. The MAX PSI is for when you have the MAX weight on each tire. For Ex. Say each rear tire is rated for 2000lbs and you have duals on each axle. So that gives a total load capicity of 16k lbs . OK So if you have a total of 16k on the rear axles and the tires say 80 PSI Max then in this case you need to put 80 PSI in them.

Otherwise you will wear the centers out of your tires in a very quick manor. You need to find out what the maker of the truck recommends for tire pressure at your rated load. Say empty. Most are half what the MAX PSI is if you need a generic answer.

Being most do not drive their trucks on road at high speeds for long distances the wear will not be as noticable.

But your tire wear and mileage will tell you just where you need to set them if you learn and watch them.

Higher pressure will net you more MPG (less surface area touching the ground) but it will in turn eat your tires. Each truck has its own happy medium you just have to find it.


And for a prime example.

I loaned my brother my 2500 Ram CTD over the winter last year to drive since he needed a car and couldn't afford one. Its E range tires are 80PSI Max. Well being the idiot my brother is trying to help he actally checked the PSI in the tires one day at the fuel station. (I am stunned he even did this.) But anyway they were at 35 front 40 rear. He then filled them all up to 80. I got the truck back this summer in July (After I bought him a Jeep Cherokee because he kept damaging my truck) to find out all 4 tires were bald in the center after the 3500 miles he put on it. So it now has new tires.

And FYI that winter he managed to make me get a new windsheild, New hood, New hinges, and took out a 35' light pole on the side of the street with my cow killer front bumper. If that bumper was not on there I would have lost the truck. I have still yet to fix the bumper and replace the broken headlight buckets.

Sigh


If any of you ever meet my brother. Don't loan him something with wheels.

not trying to argue here but my experience has been to run the recommended psi as stated by the tire manufacture. i currently have 110,000 miles on a set of michelin's under my super duty. all of those miles have been with max pressure in the tires with out any uneven wear and i was lazy and only rotated them twice. i also know that the lower the pressure, the hotter the tire will run. just my experience.