Tire pressure

[Tireman9]

I would suggest you use the inflation shown on the tire placard. Others can advise it's exact location but it should be near the driver's left arm.

After you get actual weights then you know the minimum inflation. I would run 10% higher inflation.

Lots of information on my Blog on RV tires.

[baddmann]

Originally Posted by Tireman9

I would suggest you use the inflation shown on the tire placard. Others can advise it's exact location but it should be near the driver's left arm.

After you get actual weights then you know the minimum inflation. I would run 10% higher inflation.

Lots of information on my Blog on RV tires.

I know I am probably beating a dead horse by now, but here goes:

With the Berkshire (up to 2014), Forest River put tires/airbags that are right on the edge of the max weight they can support, and that requires max air pressure recommended by Michelin. In some cases, people are over weight even running max air pressure. If you change to different size tires/airbags then you can carry more weight (up to the axle's limit).

In some cases (like mine) the tire placard is incorrect because of the wrong weight or wrong tire size listed.
Example: my tires on my coach are Michelin 255/80R22.5. I have been running 105 in the front based on tire placard. Except my tire placard says the tires are 275/80R22.5. After I had my coach weighed, I need to run 110 which is the max cold psi for the 255 tire to support the weight. (even then I am overweight by 400lbs).

Forest River is changing my tires and airbags to correct this issue.


Bottom line: Different tire manufacturers recommend different pressures for different tire sizes based on weight. There is no "one size fits all". Weigh your coach and look at the tire tables for your exact tire so that you will know what pressure to run. That is the only way to be sure.

[Tireman9]

Originally Posted by baddmann

I know I am probably beating a dead horse by now, but here goes:

With the Berkshire (up to 2014), Forest River put tires/airbags that are right on the edge of the max weight they can support, and that requires max air pressure recommended by Michelin. In some cases, people are over weight even running max air pressure. If you change to different size tires/airbags then you can carry more weight (up to the axle's limit).

In some cases (like mine) the tire placard is incorrect because of the wrong weight or wrong tire size listed.
Example: my tires on my coach are Michelin 255/80R22.5. I have been running 105 in the front based on tire placard. Except my tire placard says the tires are 275/80R22.5. After I had my coach weighed, I need to run 110 which is the max cold psi for the 255 tire to support the weight. (even then I am overweight by 400lbs).

Forest River is changing my tires and airbags to correct this issue.

I agree with others in this thread (Phil, Mmnsc, Campin Cajun) because we have researched and discussed this for a while. If don't own a Berkshire, you probably aren't as informed on this issue. That is why we ask what kind of MH you have. It makes a difference on this forum.

Bottom line: Different tire manufacturers recommend different pressures for different tire sizes based on weight. There is no "one size fits all". Weigh your coach and look at the tire tables for your exact tire so that you will know what pressure to run. That is the only way to be sure.

Glad to hear you were able to get FR to correct the situation. Did you report the violation the NHTSA? I would be surprised if there was only one RV made with incorrect placard information. We are talking about violating Federal Safety regulations here.

I don't remember hearing about a recall by FR.

[accumack]

There is a thread about the weight issue and Forest River Berkshire group is taking good care of us with the issue. Not every Berkshire model has the weight problem that is why you need to get the coach weighed with full fuel,propane, empty tanks and empty coach except for driver and spouse.

[jadatis]

Originally Posted by baddmann

I know I am probably beating a dead horse by now, but here goes:

With the Berkshire (up to 2014), Forest River put tires/airbags that are right on the edge of the max weight they can support, and that requires max air pressure recommended by Michelin. In some cases, people are over weight even running max air pressure. If you change to different size tires/airbags then you can carry more weight (up to the axle's limit).

In some cases (like mine) the tire placard is incorrect because of the wrong weight or wrong tire size listed.
Example: my tires on my coach are Michelin 255/80R22.5. I have been running 105 in the front based on tire placard. Except my tire placard says the tires are 275/80R22.5. After I had my coach weighed, I need to run 110 which is the max cold psi for the 255 tire to support the weight. (even then I am overweight by 400lbs).

Forest River is changing my tires and airbags to correct this issue.

I agree with others in this thread (Phil, Mmnsc, Campin Cajun) because we have researched and discussed this for a while. If don't own a Berkshire, you probably aren't as informed on this issue. That is why we ask what kind of MH you have. It makes a difference on this forum.

Bottom line: Different tire manufacturers recommend different pressures for different tire sizes based on weight. There is no "one size fits all". Weigh your coach and look at the tire tables for your exact tire so that you will know what pressure to run. That is the only way to be sure.

Bolded the part of my reaction.
In your case you even could have used higher pressure then 110.
This is not the maximum allowed cold pressure of a tire but the pressure at wich the maximum load can be carried up to maximum speed of tire ( yours probably only 75m/h) , without any part of rubber gets that hot that it hardens and damages in next bendings ( this to the calculation of tire-makers).

Then there are 2 things important, one is to keep within the rules and regulations of tire organisations, and second more important is to stay within the rules of nature.

To the rules of nature you can probably use even 130 psi to have enaugh reserve for things like , pressure loss in time, loadshifting on the axle R/L, etc. And the tire can handle that without blowing by to high pressure.
Even the highening up of pressure by rising of temperature in tire the tire can handle.

But not if its already damaged by overheating , by using to low pressure for the weight on tire and speed used.

[Airdale]

Motorhomes are loaded to GVWR not total GAWR. Here is a quote from a NHTSA Q&A information PDF:

“The FMVSS have requirements for the manufacturer to use proper tires and rims for the gross axle weight rating (GAWR) and the gross vehicle weight rating (GVWR). The manufacturer may determine the GVWR by adding cargo capacity (if any) to the curb weight of the vehicle as manufactured. The wise consumer, before purchase, will determine if the vehicle has sufficient cargo capacity to carry the weight of water, additional equipment (such as televisions, and microwave ovens), and luggage. The manufacturer’s certification label must show the GVWR. The GVWR must not be exceeded by overloading the vehicle. There is little the government can do to assist a consumer who has purchased a vehicle that has insufficient cargo capacity for its intended use.”
.
Because of the way vehicle manufacturers set GAWR and select tire fitments for them the recommended cold tire pressures should always be valid unless the vehicle is overloaded (total vehicle weight is higher than GVWR) or unbalanced (cargo management) causing a wheel position or axle to be overloaded.

Vehicle owner manuals, even generic ones, must provide a section on tire safety ) it’s mandated by NHTSA). What I’ve said above can also be found in your owner’s manual. So what I’m getting at is; Are you managing your tire pressures because of overloading or unbalanced conditions.

http://idn.tweddle.com/forestriver/manual?itemtype=UG&brand=Forest_River_RV&model=Cla ss_A_Diesel&language=EN_US&year=2015&market=US&idn _session=hdsifknu23oeuqfrrcme282jn4
http://idn.tweddle.com/forestriver/manual?itemtype=UG&brand=Forest_River_RV&model=Cla ss_A_Diesel&language=EN_US&year=2015&market=US&idn _session=hdsifknu23oeuqfrrcme282jn4
　
The following regulation excerpts apply.

“The weight value for load carrying capacity on the RV load carrying capacity labels must be displayed to the nearest kilogram with conversion to the nearest pound and must be such that the vehicle's weight does not exceed its GVWR when loaded with the stated load carrying capacity. The UVW and the GVWR used to determine the RV's load carrying capacity must reflect the weights and design of the motor home as configured for delivery to the dealer/service facility. If applicable, the weight of full propane tanks must be included in the RV's UVW and the weight of on-board potable water must be treated as cargo.”
　
If weight exceeding 45.4 kg (100 pounds) is added to a motor home between final vehicle certification and first retail sale of the vehicle, the load carrying capacity values on the RV load carrying capacity labels must be corrected.

Bottom line: Tire inflation pressures can be managed as long as all safety precautions are observed. First you must have tires that provide some reserves - by inflation - above the recommended inflation pressures. Do not add inflation pressures that will exceed the maximum load capacity of the tires. Look on the individual tire’s sidewall for maximum load capacity values.

Never use less inflation pressures than what has been recommended on the vehicle’s certification label.
When plus sizing up from your OE tires you may need to determine what the recommended inflation pressures are for the replacement tires. If they require adjustments auxiliary tire placards are allowed and can be hand written and placed adjacent to the certification label. You should also make notations in the vehicle owner manual. An experienced and savvy tire installer may automatically do that for you.

Tire manufacturers are notorious for not providing 100% of the information needed to make sound decisions about their product and it’s fitment regulations and standards.

The procedure to support the load carried by inflation needs scrutinization. A loss of a single psi of tire inflation pressure causes a loss of 1.6% of it’s load capacity.


I just knew nobody would write NHTSA.

[accumack]

Originally Posted by Airdale

Motorhomes are loaded to GVWR not total GAWR. Here is a quote from a NHTSA Q&A information PDF:

“The FMVSS have requirements for the manufacturer to use proper tires and rims for the gross axle weight rating (GAWR) and the gross vehicle weight rating (GVWR). The manufacturer may determine the GVWR by adding cargo capacity (if any) to the curb weight of the vehicle as manufactured. The wise consumer, before purchase, will determine if the vehicle has sufficient cargo capacity to carry the weight of water, additional equipment (such as televisions, and microwave ovens), and luggage. The manufacturer’s certification label must show the GVWR. The GVWR must not be exceeded by overloading the vehicle. There is little the government can do to assist a consumer who has purchased a vehicle that has insufficient cargo capacity for its intended use.”
.
Because of the way vehicle manufacturers set GAWR and select tire fitments for them the recommended cold tire pressures should always be valid unless the vehicle is overloaded (total vehicle weight is higher than GVWR) or unbalanced (cargo management) causing a wheel position or axle to be overloaded.

Vehicle owner manuals, even generic ones, must provide a section on tire safety ) it’s mandated by NHTSA). What I’ve said above can also be found in your owner’s manual. So what I’m getting at is; Are you managing your tire pressures because of overloading or unbalanced conditions.

http://idn.tweddle.com/forestriver/manual?itemtype=UG&brand=Forest_River_RV&model=Cla ss_A_Diesel&language=EN_US&year=2015&market=US&idn _session=hdsifknu23oeuqfrrcme282jn4
http://idn.tweddle.com/forestriver/manual?itemtype=UG&brand=Forest_River_RV&model=Cla ss_A_Diesel&language=EN_US&year=2015&market=US&idn _session=hdsifknu23oeuqfrrcme282jn4
　
The following regulation excerpts apply.

“The weight value for load carrying capacity on the RV load carrying capacity labels must be displayed to the nearest kilogram with conversion to the nearest pound and must be such that the vehicle's weight does not exceed its GVWR when loaded with the stated load carrying capacity. The UVW and the GVWR used to determine the RV's load carrying capacity must reflect the weights and design of the motor home as configured for delivery to the dealer/service facility. If applicable, the weight of full propane tanks must be included in the RV's UVW and the weight of on-board potable water must be treated as cargo.”
　
If weight exceeding 45.4 kg (100 pounds) is added to a motor home between final vehicle certification and first retail sale of the vehicle, the load carrying capacity values on the RV load carrying capacity labels must be corrected.

Bottom line: Tire inflation pressures can be managed as long as all safety precautions are observed. First you must have tires that provide some reserves - by inflation - above the recommended inflation pressures. Do not add inflation pressures that will exceed the maximum load capacity of the tires. Look on the individual tire’s sidewall for maximum load capacity values.

Never use less inflation pressures than what has been recommended on the vehicle’s certification label.
When plus sizing up from your OE tires you may need to determine what the recommended inflation pressures are for the replacement tires. If they require adjustments auxiliary tire placards are allowed and can be hand written and placed adjacent to the certification label. You should also make notations in the vehicle owner manual. An experienced and savvy tire installer may automatically do that for you.

Tire manufacturers are notorious for not providing 100% of the information needed to make sound decisions about their product and it’s fitment regulations and standards.

The procedure to support the load carried by inflation needs scrutinization. A loss of a single psi of tire inflation pressure causes a loss of 1.6% of it’s load capacity.


I just knew nobody would write NHTSA.

I'm sitting scratching my head I have no idea what you just said. All I know is my coach was over weight before the upgrade before any thing was in the coach and it is being taken care of. I know what my tires can carry and the weight of my coach. The Berkshire guys have a handle on what is happening . By the way I haven't heard of the Berks blowing tires like the all the trailer posts there are blaming Chinese tires I think they need some help there.

[tvj]

Wow I enjoyed reading this stream of knowledge. I just came back from Camp FL. I say run your tires closer to the max. Why you ask? I CAT scaled my 2015 Berkshire 40BH then had the FL SS scale all 4 wheels. So I hope u get a kick out of this. The Cat scales showed 1000 lbs more than the FL SS, ND even more interesting both front wheels were identical and so were both rear wheels. So we know that's not possible! They agreed to scale the next morning, keep in mind I am parked at the FL SS. The 1st quest was did I take on 500lbs of H20? And no I didn't. So they scaled it 2 more times and came up with 2 new scale sheets which didn't match either but still never close to the Cat scales. If interested I will post all of the sheets.

[tvj]

ND= and and SS = service center

[Phil57]

I have seen several 15's with Michelins. Other then a individual issue or two I always thought they were a good tire. Are you having problems

[tvj]

Nope have 10k on unit so far

[tvj]

Wish I had the new Axel and v-ride

[Phil57]

Originally Posted by tvj

Wish I had the new Axel and v-ride

What exactly is the new V ride?

[accumack]

Originally Posted by jadatis

Bolded the part of my reaction.
In your case you even could have used higher pressure then 110.
This is not the maximum allowed cold pressure of a tire but the pressure at wich the maximum load can be carried up to maximum speed of tire ( yours probably only 75m/h) , without any part of rubber gets that hot that it hardens and damages in next bendings ( this to the calculation of tire-makers).

Then there are 2 things important, one is to keep within the rules and regulations of tire organisations, and second more important is to stay within the rules of nature.

To the rules of nature you can probably use even 130 psi to have enaugh reserve for things like , pressure loss in time, loadshifting on the axle R/L, etc. And the tire can handle that without blowing by to high pressure.
Even the highening up of pressure by rising of temperature in tire the tire can handle.

But not if its already damaged by overheating , by using to low pressure for the weight on tire and speed used.

So you are saying we should ignore what the tire manufacturer says and put 130psi in our tires? Most of us run tire monitors and know tire temp and pressure. We probably know more about our tires than most other people. Your help is sorely needed in the trailer forums are they are losing tires left and right and have much less of an understanding than we do. Most have no clue as to the weight they are carrying and the speed limit of their tires. Please help them!

[asquared]

Originally Posted by accumack

So you are saying we should ignore what the tire manufacturer says and put 130psi in our tires? Most of us run tire monitors and know tire temp and pressure. We probably know more about our tires than most other people. Your help is sorely needed in the trailer forums are they are losing tires left and right and have much less of an understanding than we do. Most have no clue as to the weight they are carrying and the speed limit of their tires. Please help them!

This would be an incorrect statement. Just as berk owners understand their tires and run tpms, so do many trailer owners. Many trailer owners also upgrade their tires and weigh their rigs. Just because someone does not own the exact thing you do does not mean they don't understand a concept. Consider this one last moderator warning to this thread about the shameful attitude displayed by many of you on here. These are public forums and everyone has the right to post here. We take the play nice rule very seriously and this attitude does not lend itself to how these forums are intended to be run. If you do not have something nice to say, please refrain from posting it. The site team has had enough of this and will begin issuing strikes for this kind of behavior.

[Phil57]

Originally Posted by asquared

This would be an incorrect statement. Just as berk owners understand their tires and run tpms, so do many trailer owners. Many trailer owners also upgrade their tires and weigh their rigs. Just because someone does not own the exact thing you do does not mean they don't understand a concept. Consider this one last moderator warning to this thread about the shameful attitude displayed by many of you on here. These are public forums and everyone has the right to post here. We take the play nice rule very seriously and this attitude does not lend itself to how these forums are intended to be run. If you do not have something nice to say, please refrain from posting it. The site team has had enough of this and will begin issuing strikes for this kind of behavior.

Taking part on the FROG forum should be fun and educational. Of coarse it can't always be because not everyone is nice. When that forum users get upset things can go bad quickly because we are not all great communicators in the written word. I have been beside myself mad because of how I have been talked to in this forum several times but usually find a way to get over it and hopefully haven't left to many folks hating my guts out there.
I agree that this is a public forum and we all have a right to post on all sections of the forum. I think that what gets folks upset are two things.
1: incorrect information passed off as and expert. We all know what they are saying is incorrect but we worry about the new folks that will not and might be dangerous. I guess I need to find a nice way to tell someone they are full of crap.
2: the constant complaining and attempt to slander and stain FR's reputation on the forum. As I read the rules this should not be allowed. I have personally taken much heat both publicly and in PM's that have been hurtful and mean. Why when we are having a nice conversation about a MH owner that had FR come through and do all the repairs on their rig do we have to be nice to some loud mouth person that searches every post so he can complain. Why are comments like "FR is crap aloud" or When a forum member says FR is a great company someone posts "FR is not a great company" said only to make people mad.? I'm sick of it. It's all Over the forum and the admins have done nothing to stop it. That is neither helpful or fair to FR.
Now if someone is frustrated and vents a bit while wanting help I understand and I have done that. I will not set back and ignore those comments. I will continue to catch heat from it and then all the sudden I'm an elitist.
Maybe we need to understand the rules better. Can we just go on trashing FR In every post. Is this allowed? What is the recourse if it's not. If it is maybe I need to find another forum.
I do appreciate the job done by most of the admins. It's a tough job I understand that. I however do not think that the no bashing rule is enforced as it should be.
Thanks for listening and thanks for the good job that you do. Sorry if I'm out of line here but I feel strongly that this forum has been allowed to go down hill lately.

[accumack]

We were being told to run 130 psi way beyond manufacturers recommendations of 110psi max printed on the side wall.

[Campin Cajun]

Is there a way to block a thread from showing up on my iPad? Please tell me.......please.

[Paulie Boy]

Fellow Berk owners, let this thread die. It is counterproductive and a dead end street.
We all have better things to do.


Paul

[Phil57]

Originally Posted by accumack

We were being told to run 130 psi way beyond manufacturers recommendations of 110psi max printed on the side wall.

I agree. If someone puts 130psi in their tires it could and most likely would cause a very bad accident. I'm at a loss as to what all the tire expert comments were about. This is not a complicated subject. Get your Moho weighted and follow the manufacture recommended psi for that weight. So as I said we do need a tactful way to tell someone that they are full of crap. I personally do not like the us against them idea. I have many many friends that I have learned a lot from on this forum that do not own a Moho. I do not want them to stop giving advice on the Berkshire page. I do not want them to think that we don't want them on the Berkshire page. I don't want people to think of Berkshire owners as elitist or worse. But I also would love it if people would read the posts before making an Irrelevant post.