Tire pressure question

[tinman 55]

I have searched the prior forum posts but still have questions about the tire pressures on my new to me 2006 Country Coach Allure Sunset Bay that I hope someone can help me with.

I recently purchased this coach and as yet been unable to find a place that can weigh the coach on all four corners as I see is recommended. The coach has new Yokohama 295-80x22.5 tires and I noticed it had a little road wander when I first drove it. The front tire pressure was set at 120 which I have since reduced to 110 which has greatly improved the steering. The rears are set at 100 each. The tag in the coach shows recommended pressures of 120 in the front and 95 in the rear.
The only weights I have on the coach were those provided to me in the original Country Coach information binder which shows the coach was weighed in May 2006 with weights as follows.
LF-5531. RF-5734. LR-11101 RR-12564

Until I am able to get a proper four corner weight, do my pressures seem okay? Also, how do I get a proper weight if the tag axle cannot be independently weighed. Do I take a total rear drive axle weight and divide it by four to compensate for the tag?

While we are talking tires, does anyone have a recommendation for tire pressure monitors that will work with my Silverleaf system?

As always, I thank you in advance for you help

[Gary Wittig]

I have a 2007 CC Allure 430 with Toyos. Are the tire pressure numbers (that you provided) cold or hot? I have found the following cold numbers to be the best to run with:110psig front, 100psig rear drive along with tag. Any higher pressures and the ride becomes harsh. I can pick up 15psig once the tires heat up depending on the road surface temperature.

[Jubilee 45]

I have the oh six intrigue 45’. The plate on the wall left of the driver seat aft of the council states 120 in front 95 in rear drive and tag. It runs true like this but the front seems hard on rough roads.

[CountryFit]

There are a lot of threads on tire, you may search it on Class A forum and read them in days...

Generally the tire pressures specified on the tag on the cockpit wall and the ratings on the tire wall are for cold (coach not driven overnight). The manufacturers have already considered the pressure flutuation when tire gets hot, no worry about it. I keep my tire pressures the same to the CC recommended numbers (front 120 rear 110) and ride is stll smooth. it is probably true that the #1 enemy of the tire is under inflation. If you observe 18 wheeler's tires they are really round.

The wandering on the road can be caused by many things. One thing that cured mine was the ride height adjustment (took many years for me to get it though).

Dividing the rear axle weight by 4 is a common practice (if you have duallies and no tag axles). It's hard to find a 4 corner weighing station. The only one I heard was Escapees that they have portable units, but people complained about their inaccuracy.

As for TPMS, many people are happy with TST. I picked up a TireMinder (Camping World has it) in 2013 and still use it today. It alarmed me overheating on the steep and streching slope at west of Denver years ago that alone probably saved me a big money on the front hubs.

Enjoy your new rig!

[tinman 55]

Originally Posted by Gary Wittig

I have a 2007 CC Allure 430 with Toyos. Are the tire pressure numbers (that you provided) cold or hot? I have found the following cold numbers to be the best to run with:110psig front, 100psig rear drive along with tag. Any higher pressures and the ride becomes harsh. I can pick up 15psig once the tires heat up depending on the road surface temperature.

The pressures are cold Gary. Was probably in the neighborhood of 65 degrees or so when I set them. Thanks for the reply

[tinman 55]

Originally Posted by Jubilee 45

I have the oh six intrigue 45’. The plate on the wall left of the driver seat aft of the council states 120 in front 95 in rear drive and tag. It runs true like this but the front seems hard on rough roads.

My tag also has the same pressure settings as you mentioned.

[tinman 55]

Originally Posted by CountryFit

There are a lot of threads on tire, you may search it on Class A forum and read them in days...

Generally the tire pressures specified on the tag on the cockpit wall and the ratings on the tire wall are for cold (coach not driven overnight). The manufacturers have already considered the pressure flutuation when tire gets hot, no worry about it. I keep my tire pressures the same to the CC recommended numbers (front 120 rear 110) and ride is stll smooth. it is probably true that the #1 enemy of the tire is under inflation. If you observe 18 wheeler's tires they are really round.

The wandering on the road can be caused by many things. One thing that cured mine was the ride height adjustment (took many years for me to get it though).

Dividing the rear axle weight by 4 is a common practice (if you have duallies and no tag axles). It's hard to find a 4 corner weighing station. The only one I heard was Escapees that they have portable units, but people complained about their inaccuracy.

As for TPMS, many people are happy with TST. I picked up a TireMinder (Camping World has it) in 2013 and still use it today. It alarmed me overheating on the steep and streching slope at west of Denver years ago that alone probably saved me a big money on the front hubs.

Enjoy your new rig!

Thank you very much for your reply. Yes, I've been reading post after post which there are many, just trying to get a close baseline. I certainly don't want to have a blowout, or ruin the new tires.

Ive found a local freight moving company who has a scale but not enough room to drive the coach off the side apron to get a true one sided measurement. I called the local CAT scale at a nearby truck stop which has the room and was told they are just too busy to have me jockeying the coach around for different weights. So, I will keep looking.

Thanks a bunch for the TPMS info, I will get to reading.

[Smitty77]

Until you do get Four Corner Weight (Well, actually 6, with the Tag's!)... You could use the weights from CC when they built the coach. It will not included your loaded ready to go added gear/food/etc. So suggest adding say 1,500 pounds to the Steers, and Tag, and 3000 pounds to the Duals. (MORE, all around, if you feel you are traveling especially heavy with gear...).

Our 40' Allure 2 slide with tag. Below is a Cut & Paste of what I ran with. (Except I admit, over the last few years of owning, for ease of memory - I ran 100 PSI in Rear and Tag. No noticeable change in ride comfort.)

AND I CAUTION THIS IS JUST FYI INFO... The only real safe way to set PSI, is after Four Corner Weight, and of course, specifically accessing the Tire Manufactures Weight to PSI for your specific set of shoes!

But, it might be info to help you come up with a safe setting, below Placard levels - until you get your weights!

Best to you, and all,
Smitty

====== Copy of Working PSI Numbers ======

2004 Allure High Cascade, 40' with two slides. SN 31017





From Escapees SmartWeight 3/17/2016

Coach ready to roll with full fuel, water, packed for a trip. Since last weight check, we've added:
X's 4 L16 AGM, X's 5 Solar Panels to the Right side of the coach.
Oh, and the under the J-Lounge Wine Storage was stocked for 'extended travels too. Also Right side.


L Front - 5800
R Front - 6100
(Combined) - 11,900
(Weight to be used for Axle Weight) - 12,200

L Rear Drive - 7800
R Rear Drive - 8250
(Combined) - 16,050
(Weight to be used for Axle) (Note: Drive often called Duals.) - 16,500

L Tag - 3800
R Tag - 4200
(Combined) - 8000
(Weight to be used for Axle Weight ) - 8400


Total Weight - 35,950

Toad Weight - 3475

Combined Weight - 39,425

ISL400 HP is at 90/1 without toad, and just about 100/1 with toad.

======================

All tires 12R 22.5 size, Load Range H

>Steers/Front Michelin XZA2

6100 = 90 PSI (Line Single Weight of 12,410) - plus - 10% = 9. PSI | Use 100 PSI

TST = Low 90 PSI High 145PSI

TST Note: Use default 157 F Temperature for all positions

>Rears/Drives Michelin XZA2

8250 = 75 PSI (Dual Line of 9980 (Their Minimum PSI and listed Weight) - plus - 10% = 7.5PSI | Use 82.5 rounded up to 90 PSI

TST = Low 85 PSI High 145 PSI

>Tags are BF Goodrich ST230

8400 = 75 PSI plus 10% 7.5PSI | Use 82.5 round up to 90 PSI

Run the same as the Rear/Drive tires | Use 90 PSI

TST = Low 85 PSI High 145 PSI

Note: All of our weights were not too close to the next line on the PSI charts. If they were within 20% or so from the next line level,
I would have bumped up next line and used it's PSI.


Toad TST Settings

Low 29 PSI High 45 PSI

[tinman 55]

Thank you Smitty.
I see the importance of proper weighing. My weight tag in the coach recommends 95 PSI in rear drive and tag axle. I have looked at the PSI chart for Yokohama and found 95 PSI to have a max load rating of 5645. Im trying to figure out how that calculates. If I multiply it by 4 for just the duals, I get 22,580 total which is a thousand pounds lighter than what Country Coach weighed it at in 2006. And, multiplying it by 6 to compensate for the tag axle throws it way off.
I think what I have them set at is safe until I can get it weighed correctly. The PSI chart shows a weight rating at 100 pounds as 5885

Does anyone in So. California know of a place I can have it weighed correctly?

[Tee Jay]

Henderson's in Grants Pass will do a 6 side weigh. Colton Truck may also do it, and some heavy truck dealers may as well.

The tire ratings have a value for duals and one for singles, and it is nowhere near divide by two. Tire wear is an indicator, too much air and the center wears a bit faster and mileage may marginally improve, too little and the edges show wear. The tire dealer can tell you what the pressures should be at various weights.

[IASM]

most all truck stops have scales. While they will be per axle that will give you a good idea as to what kind of weight your running on each axle. I see a lot of truck weight stations that while closed they leave the digital scale turned on. I stop at those and double check. You can get a 4 corner by weighting the total axle load then move over and place just the right side tires on the scale.subtract that from total axle load and you have the left tire numbers. With air suspension it tends to help keeps things more balanced.

[tinman 55]

Originally Posted by Tee Jay

Henderson's in Grants Pass will do a 6 side weigh. Colton Truck may also do it, and some heavy truck dealers may as well.

The tire ratings have a value for duals and one for singles, and it is nowhere near divide by two. Tire wear is an indicator, too much air and the center wears a bit faster and mileage may marginally improve, too little and the edges show wear. The tire dealer can tell you what the pressures should be at various weights.

Thank you, I will call Colton tomorrow as I'm a half hour away. If not, I think I found a scale that I can at least way each side as well as a total weight.

[tinman 55]

Originally Posted by IASM

most all truck stops have scales. While they will be per axle that will give you a good idea as to what kind of weight your running on each axle. I see a lot of truck weight stations that while closed they leave the digital scale turned on. I stop at those and double check. You can get a 4 corner by weighting the total axle load then move over and place just the right side tires on the scale.subtract that from total axle load and you have the left tire numbers. With air suspension it tends to help keeps things more balanced.

Thank you for the heads up about the closed truck stops. I never thought of stopping at a closed one, figured it would be off limits. I will give it a try.

[KanzKran]

If you want to get the tag weight, you might have to weigh the coach with the front axle on the front pad, and the drive and tag on the middle pad at a CAT scale. Then either move it, or go around, for a second weight with the drive on the front pad and the tag on the middle pad and possibly the front off the scale.

Reweighs are cheaper than the initial weigh, within something like a 24 hour period.

That won’t get you a ‘4-corner’ weight, but it’ll put you in the ball park. Presumably the weights CC gave you in the book are UVW (unladen vehicle weight), so you’re almost certainly quite a bit heavier than that now, with water, propane, waste tanks (if not empty), and all the other stuff you carry, including people.

Right now one rear corner is something like 12% heavier than the other, but I suspect it’s because it was empty when CC weighed it, not loaded as you would be for actual use. Add 5%, or 10% if you like, to the recommended cold air pressure from the tire manufacturer’s tables for that size tire to allow for end-to-end imbalance. Adjust from there once you get a 4-corner weight, but always run the same pressure on both ends of the same axle - don’t use different pressures to compensate for different loads on each end of each axle.

https://catscale.com/cat-scale-locator/

https://catscale.com/how-to-weigh/