Another tire pressure load chart thread……lol

[IAlreadyGot1]

Originally Posted by Sgt B

Michelin's tire chart is not like that, shows only single and dual for each tire size
and type. There are 1-4 sets of asterisks, but the pic he shows only shows what one asterisk means, what does 2, 3, and 4 mean? Showing two pressures for the exact same tire does not make any sense to me.

The asterisks on the Tokyo chart refer to various size Michelin equivalents.

I agree that the Toyo chart is confusing, which is why this thread was started. There is however, just enough information on the chart to identify the OP’s tire.

[Cuda67bnl]

Originally Posted by Alpine36

Your CAT scale weights are nearly identical to our 36 FDS. (yours being about 300lb heavier in the rear)
I've found 95psi cold front and rear just about ideal. They "grow" to about 102-107psi at 85-90 degrees temp.
They were originally set at 110 by the installer and the ride was rough, steering a little twitchy.
I believe WRV recommends 95psi all the way around for our chassis.
10k miles on our six 295/75/22.5 H steer tires, no unusual wear issues, great ride and handling. Now if I can figure out why the new TST507 tpms gives occasional false alarms...

I’ve been running 100 pounds, but dropped them them to 95 this morning to see if it drove better. Wasn’t impressed with the first half of our trip today, but I’m hoping it was just a crappy road, coupled with my new toad pushing us around. Second leg of the drive was better. WRV has 95 on the placard, but says to set by weight in the owners manual. Since these aren’t the original rated tires, I figured I’d experiment. Just didn’t wanna set em too low. Curious what alarms you’re getting? My tireminder saved me a week or so ago when the brakes were sticking on the toad. At first I thought it had just dropped signal on a tire, as that happened on a rear coach tire when I forgot to turn the repeater on one time. But it was the temp alarm.

[Alpine36]

Originally Posted by Cuda67bnl

I’ve been running 100 pounds, but dropped them them to 95 this morning to see if it drove better. Wasn’t impressed with the first half of our trip today, but I’m hoping it was just a crappy road, coupled with my new toad pushing us around. Second leg of the drive was better. WRV has 95 on the placard, but says to set by weight in the owners manual. Since these aren’t the original rated tires, I figured I’d experiment. Just didn’t wanna set em too low. Curious what alarms you’re getting? My tireminder saved me a week or so ago when the brakes were sticking on the toad. At first I thought it had just dropped signal on a tire, as that happened on a rear coach tire when I forgot to turn the repeater on one time. But it was the temp alarm.

We just did a 700 mile quickie roadtrip to Idaho and back. Had two false "low pressure" alarms. One on the Jeep which cleared after 30 seconds and one on the LR inner dual that the audible alarm stayed on steady for miles.
Both for no particular reason, but pulled over as soon as safely possible and checked anyhow. At no time did either suspect tire sensor show abnormal pressures or tempatures. Just the low tire pressure icon illuminated and the suspect tire flashing on the screen with audible beeping. The repeater is installed as per instructions and was on. TST says it could possibly be caused by our indoor/outdoor thermometer, both operate at 433mhz.
Weird.
If it continues to give false alarms it's going back.

P.S.
I just replaced our Wranglers calipers and rotors X 4 this spring.
They started dragging so hard I barely made it back home one day. Thankfully it didn't happen while in tow. So that makes all new brakes on the whole shebang. The Firestone bags are still on backorder from Michigan Truck Springs, but those new Koni 99s up front are fantastic.

[Ray,IN]

Firestone, Goodyear, and some other truck tire mfgrs. say to never run less than the Federal Tire Placard the vehicle mfgr placed on the vehicle if their load/inflation charts show less.

[IAlreadyGot1]

Originally Posted by Cuda67bnl

I’ve been running 100 pounds, but dropped them them to 95 this morning to see if it drove better. Wasn’t impressed with the first half of our trip today, but I’m hoping it was just a crappy road, coupled with my new toad pushing us around. Second leg of the drive was better. WRV has 95 on the placard, but says to set by weight in the owners manual. Since these aren’t the original rated tires, I figured I’d experiment. Just didn’t wanna set em too low. Curious what alarms you’re getting? My tireminder saved me a week or so ago when the brakes were sticking on the toad. At first I thought it had just dropped signal on a tire, as that happened on a rear coach tire when I forgot to turn the repeater on one time. But it was the temp alarm.

You certainly have plenty of tire for your weights. It would be interesting to conduct a blind test with tire pressures set at 95, 100 & 105, to see with what degree of accuracy the driver could “guess” the correct pressure. My prediction is that incorrect guesses would dominate the results.

Given your weights and axle ratings of 12K front and 19K rear, it’s possible that a LRG tire with a lower minimum pressure requirement, at least on the rear axle, might allow for a more pleasant ride than the particular LRH tire that you’ve selected, which appears to have a minimum required pressure of 95psi. It could that more isn’t better in this case.

As for the repeater, if you can locate and utilize an ignition switched power source for the device, it will always be on while driving.

[mlpeloquin]

Originally Posted by Ray,IN

Firestone, Goodyear, and some other truck tire mfgrs. say to never run less than the Federal Tire Placard the vehicle mfgr placed on the vehicle if their load/inflation charts show less.

If you check, that placard on your RV, truck, or car is for the maximum weight your vehicle is rated for on the axle stated.

[Crasher]

I've always wondered why a tire company would do the testing to produce a load inflation table and then tell you to ignore it and use the placard on the coach. Don't they trust their own research???

[wolfe10]

Originally Posted by Crasher

I've always wondered why a tire company would do the testing to produce a load inflation table and then tell you to ignore it and use the placard on the coach. Don't they trust their own research???

Source #1, the engineers.


Source #2, the attorneys.



CYA trumps physics.

[Alpine36]

The placard is only accurate if the tire size and load ratings match the original equipment ratings the chassis engineers designed. If you stick to the OEM tire specs the placard tire pressure recommendations should be well within the tire manufacturers inflation tables. Of course, accurate scale weight should be done to insure you're not overweight, and pressure is within the tire manufactures spec tables. This all goes out the window if one bit of the equation isn't correct...

[IAlreadyGot1]

Originally Posted by Crasher

I've always wondered why a tire company would do the testing to produce a load inflation table and then tell you to ignore it and use the placard on the coach. Don't they trust their own research???

They pass the responsibility of recommending tire pressures to the vehicle manufacturer. Rightfully so, as the difficulty in understanding the correct method and then determining the appropriate tire pressure for a vehicle, ranks somewhere between understanding quantum physics and the meaning of life.

[Crasher]

Originally Posted by Alpine36

The placard is only accurate if the tire size and load ratings match the original equipment ratings the chassis engineers designed. If you stick to the OEM tire specs the placard tire pressure recommendations should be well within the tire manufacturers inflation tables. Of course, accurate scale weight should be done to insure you're not overweight, and pressure is within the tire manufactures spec tables. This all goes out the window if one bit of the equation isn't correct...

The placards are not as accurate as a scale and the load inflation charts. My coach placard says 110 psi in all 8 tires. That would put the front axle 5 psi under inflated, the drive 20 psi above what I could possible get in the coach unless I carried gold bars and the tag would be 35 psi above what the Load chart reads for the load. Now that was a rough ride except for when the front tires would have failed from under inflation.

[Crasher]

Originally Posted by IAlreadyGot1

They pass the responsibility of recommending tire pressures to the vehicle manufacturer. Rightfully so, as the difficulty in understanding the correct method and then determining the appropriate tire pressure for a vehicle, ranks somewhere between understanding quantum physics and the meaning of life.

I don't see how it could be any simpler. Weigh each position, get the pressure from the chart for the heaviest tire on an axle, look in the load table for the psi for that weight. Then add 10% for temperature changes and hit the road. It doesn't have to be complicated, It's just simple math.

[IAlreadyGot1]

Originally Posted by Crasher

I don't see how it could be any simpler. Weigh each position, get the pressure from the chart for the heaviest tire on an axle, look in the load table for the psi for that weight. Then add 10% for temperature changes and hit the road. It doesn't have to be complicated, It's just simple math.

My apologies. I thought the exaggeration of the difficulty level in my previous post might be a sufficient indicator of the sarcasm behind the message.

[Crasher]

Originally Posted by IAlreadyGot1

My apologies. I thought the exaggeration of the difficulty level in my previous post might be a sufficient indicator of the sarcasm behind the message.

I realized that after I posted it. However, I was right on for many that ask this same question. Does any topic get repeated on this forum more than "Tire Pressure".