Tire presure for SRW with 19.5 G rated tires?

Hi,

It seems like you have a adequate pressure. It might be a little to high, but better to error on the higher side of things. I would try 90 rear and 75 front, it might ride a bit better. There is only about 2,500 pounds on each of the front tires. Rear tires are well under 4,000 pounds, so 90 should be fine.

Fred.

PS: I hope that you already installed a coolant filter. Napa part# FIL 4070 and a kit to install it is FIL 4019. You can do the job yourself in about 2 hours with plenty of time off for coffee breaks.

I run 110psi on a single rear wheel, 85 up front loaded. Your temps sound fine. I've noticed the sun side of the vehicle can be 10deg warmer.

Also note that these are commercial class tires and DO NOT have
a safety bead on the wheel rim

So that means always keep them aired up and do NOT air them down like
one would for the lower class tires ("P" and "LT") for 'ride quality'

Load and inflation tables

your tire size is on page 45.

With a SRW pickup & 2900 pin your tire loading should be just off the low end of the load and inflation table scale.

06Fargo wrote:
Load and inflation tables

your tire size is on page 45.

With a SRW pickup & 2900 pin your tire loading should be just off the low end of the load and inflation table scale.

X2

My truck is about 4500 lbs up front and 2750 lbs on the rear when unloaded to give you a reference. If you can get yourself on the scales loaded,the inflation tables will give you optimum pressures for your load. Keep at least 70 psi in the tires when unloaded to make sure the beads stay seated.

Watch your tread wear pattern.
If the tread wears evenly across the tire, your inflation pressure has been just right.
If the tread wears in the middle more than the sides, your tires are over inflated.
If the tread wears on the sides more than the middle, your tires are under inflated.
If you are worried about it, and in a hurry, you can make a mark across the tread with chalk (any color), then drive across a hard surface (like a parking lot). Look at the wear pattern of the chalk mark.
Yes, tire inflation really IS just that simple!

Read what it says on the tire side walls for PSI. If that is too confusing then contact the tire manufacturer and ask. So what is the point you are trying to make about the tire temp? What is the max temp rating on your tires? Was the temp of the tires higher than the temp rating, if not then the temp is not a problem? Beware of the tire expert wannabes personal opinions they will not pay for tire damage their personal opinions cause.

BenK wrote:
Also note that these are commercial class tires and DO NOT have
a safety bead on the wheel rim

So that means always keep them aired up and do NOT air them down like
one would for the lower class tires ("P" and "LT") for 'ride quality'

Correct inflation is important. I respectfully disagree that a "commercial" tire will auto-fall-off-the-rim at reduced pressures under "normal" driving. It could be possible if you attempt timed slalom cornering at not normal low pressure.

BenK is correct - the rims are designed so the average bear can change a tire with tire irons and a bead breaker on the floor and sometimes right on the truck without a monumental wrasslin' match.

19.5 tire arns

Heavy trucks central inflation systems ("CTI") installed operate commercial tires at reduced but safe pressures for the speed and load. I post TireBoss link because it is the one I have used.

TireBoss inflation system video page showing loaded truck tires down to 36 psi

CTI system trucks are capable of reducing tire pressures when travelling empty to allow the tires to achieve their best performance "shape", then reinflate to correct load and inflation table pressures after loading cargo. They have safety warnings built in - if you exceed a safe speed at your inflation, it warns you to slow down. If you don't it will inflate the tires automatically.

Over inflating tires for the load will not generally bother the tire much unless it is to the point you are raising the edge of the tread off the road and causing accelerated center tread wear.

Tires are part of the suspension and when they are overinflated round rocks they allow the road to beat unnecessarily on the vehicle riding on them and don't provide the traction for braking, cornering, and go forward they are designed to do.

mowermech's method may show you something interesting - on many motorhome / rv trailers / trucks with campers the tires on not carrying an equal load on the same axle.

If you contact your 19.5 or larger tire manufacturer, and say "I'm thinking of equipping my truck with CTI. Please send me the load and inflation tables for this type of use." This table will have speed, load, and minimum inflation down to very low speeds and inflation pressures.

Keep at least 70 in them at all times for the above reasons.

I run mine at 70/70 when empty and 80/95 for normal trips but will bump them to 90/110 for longer trips. I don't need the air for weight but the run cooler. I am about 5,000/7,200 on axle weight when fully loaded.

Agree & disagree with Fargo on the low PSI and slalom example, which is a VERY
good example

As long as you can dictate

NOT

having to do a slalom
like maneuver, I'll agree with Fargo...you will be fine with too low
a PSI

BUT...if you ever have to and most likely during an emergency situation,
then you are potentially going to lose the bead on the leading, outside
radius tire to wheel

That will then drop the leading edge of the vehicle down the tire's
aspect ratio height

Worse case on that is, that the wheel rim will strike the pavement
and dig in...

How likely is this scenario? Betcha most folks will NEVER experience
that...but also betcha that there are some that will...AKA that other guy...

All part of risk management decisions...AKA gambling that, that worst
day will NOT cross your path...just the other guy's issue...

Also...PSI is NOT just for weight carry, but to maintain the tire's
shape during maneuvers. More so in extreme & emergency situations