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Topic: The wheels on the bus... (Read 1087 times) previous topic - next topic

The wheels on the bus...


...go round and round, but how do you determine how much air pressure to run in the tires?  The side walls of my Michelein tires say 110 pounds, but my owners manual says to weigh the vehicle and adjust the pressure accordingly.  Do you routinely weigh your coach to determine pressure or can you estimate?

As a follow up, can anyone tell me the torque necessary for the wheel lugs?  How often do you check the torque, after 100 miles on a tire change or more often?

Thanks,

Biscuit

Re: The wheels on the bus...

Reply #1 –
Quote from: BiscuitBoy –

...go round and round, but how do you determine how much air pressure to run in the tires?  The side walls of my Michelein tires say 110 pounds, but my owners manual says to weigh the vehicle and adjust the pressure accordingly.  Do you routinely weigh your coach to determine pressure or can you estimate?

As a follow up, can anyone tell me the torque necessary for the wheel lugs?  How often do you check the torque, after 100 miles on a tire change or more often?

Thanks,

Biscuit
Biscuit...(Oh Boy!...now I'm hungry... :)) )
Have you tried searching the site on this topic?  It's been discussed from A to Z here already.  But, after many discussions, a good percentage of folks would just inflate the tires to the sidewall maximum stated value and then if the coach ride harshness is bearable, they live with it.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: The wheels on the bus...

Reply #2 –
Quote from: Peter & Beth –
Quote from: BiscuitBoy –

...go round and round, but how do you determine how much air pressure to run in the tires?  The side walls of my Michelein tires say 110 pounds, but my owners manual says to weigh the vehicle and adjust the pressure accordingly.  Do you routinely weigh your coach to determine pressure or can you estimate?

As a follow up, can anyone tell me the torque necessary for the wheel lugs?  How often do you check the torque, after 100 miles on a tire change or more often?

Thanks,

Biscuit
Biscuit...(Oh Boy!...now I'm hungry... :)) )
Have you tried searching the site on this topic?  It's been discussed from A to Z here already.  But, after many discussions, a good percentage of folks would just inflate the tires to the sidewall maximum stated value and then if the coach ride harshness is bearable, they live with it.
Biscuit. I seriously doubt that most of us "inflate the tires to the sidewall maximum stated pressure". I have weighed my coach on a commercial scale and adjust my cold tire pressure to the assigned value for that weight. Granted the weighing was done a while back but the coach was loaded then as it is now. I did weigh the axles not the individual wheels, I have never been at a place where this was available.  I check my tire pressure before every trip and monthly, thereafter. I check the temperature of every tire at each stop while on the road (by feel).
No RV! Have hung up the keys.
In the past: 2016 Winnebago Era, 1994 Foretravel U240, 1995 Foretravel U240 (wide body), 1999 Foretravel 320, 36 Foot, 2003 Foretravel U320 38 foot,

Re: The wheels on the bus...

Reply #3 –
Oh yes. The techs check the wheel lug torque at each "service", 6000 miles.
No RV! Have hung up the keys.
In the past: 2016 Winnebago Era, 1994 Foretravel U240, 1995 Foretravel U240 (wide body), 1999 Foretravel 320, 36 Foot, 2003 Foretravel U320 38 foot,

Re: The wheels on the bus...

Reply #4 –
Biscuit,

Wheel lug torque depends on which wheels you have and whether or not the studs are lubricated.  If you have Alcoa wheels, Alcoa's web site gives the correct torque for each wheel type.  Mine are 450 to 500 foot pounds dry.  There are also discussions about torque on this forum.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: The wheels on the bus...

Reply #5 –
Biscuit,
I'll give you the following link only because it gives lots of good info.  Am not endorsing their products:  http://www.trucktires.com/bridgestone/us_eng/press/zip/RV_Brochure.pdf.
Other tire manufacturers also have the info on their web pages.  The reason for weighting at each individual corner is that many coaches can be heavier by over a thousand pounds on one corner.  Some manufacturers are not good at distributing weight or determining how you will utilitize the storage areas. 

You will find the load and inflation tables for your tires on their manufacturers web site.  Just follow the directions in the link above.
1994 U225
build #4514

Re: The wheels on the bus...

Reply #6 –
Like the above post, we inflate to the max recommended cold pressure of 110 psi at the start of each trip and every few days while under way. Thump them with a stick when I remember at stops. Most commercial operators do the same. Tires run cooler, last longer and we use less fuel.

Pierce & Gaylie
93' U300/36
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: The wheels on the bus...

Reply #7 –
Tire manufacturers spend a lot of time and money developing tire pressure charts.  Overinflating decreases contact patch (decreasing braking capability) while increasing chassis wear.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: The wheels on the bus...

Reply #8 –
We are currently at FOT. Wayne performed a wheel alignment, which significantly improved steering performance. He strongly recommended running pressures in my Michelin tires based on measured axle weight and a chart from Michelin. His chart, faxed from the factory's Michelin representative, closely matched the Michelin chart I found on the web. The pressures are significantly lower that 110 psi, the maximum cold pressure as indicated on the side walls of the tire.

Quote from: amos.harrison –
Tire manufacturers spend a lot of time and money developing tire pressure charts.  Overinflating decreases contact patch (decreasing braking capability) while increasing chassis wear.

Wayne's comments included statements like the quote from Brett's post.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: The wheels on the bus...

Reply #9 –
Yea, I just posted on this topic a couple of weeks ago. Anyhow, I was of the opinion that the manufacturer's (Michelin, in my case) recommendation was the way to go but after reading extensively here and elsewhere, I've decided to go much higher. e.g. Michelin calls for the rears at my weight (U-225) to be at 70 psi. I'm going with 100 psi instead. I think you just have to read what you can and settle on a number.
jor
93 225
95 300
97 270
99 320

Re: The wheels on the bus...

Reply #10 –
Peter and Beth,

Just realized how the search function works.  Many thanks.  Lots of good responses.

Biscuit

Re: The wheels on the bus...

Reply #11 –
Quote from: BiscuitBoy –
Peter and Beth,

Just realized how the search function works.  Many thanks.  Lots of good responses.

Biscuit
Biscuit,
Good to hear you're learning how to navigate the ForeForums.  Also, Barry Brideau's web site beamalarm.com contains a world of information just for Foretravels.  The web site can be found in the "Links" section here.
 
BTW, I do not use the side wall max pressure on my Load Range G Michelins as the 34 ft. coach is rather light.  I tried it once and almost bounced off the road...well, almost...well...I may be exagerating a bit.  You really do need to weigh the coach in order to know your options, but you need to know the minimum air pressure for each axle.
 
Even if one side of the axle weighs more than the other, you need to use the higher weight "air pressure" on both sides on that axle...FYI...
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH
 

Re: The wheels on the bus...

Reply #12 –
Quote from: Peter & Beth –
You really do need to weigh the coach in order to know your options, but you need to know the minimum air pressure for each axle.

Just FYI, the latest Escapees magazine has an article on the club's new SmartWeigh program.  In a nutshell, they are installing weighing equipment at some of the Escapees parks, and for a fee you can get your coach individual wheel weights by appointment.  Rainbow's End is in Livingston, fairly close to Nac, as one option.

http://www.escapees.com/SmartWeigh/

The individual weights are great to help you know how to distribute your "stuff" as well as proper tire inflation.

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320