New Tires

Got reply from Continental regarding load vs. PSI table:


Jennifer,


Please find below, specified PSI inflation pressures recommended for 245/70R19.5 size products:

  PSI          80      85      90      95      100      105      110      115      120                                                     
  Dual      3415  3515  3655  3860(F)  3940  4075  4300(G)  4345  4540(H)
  Single    3640  3740  3890  4080(F)  4190  4335  4540(G)  4620  4805(H)

You need to adjust inflation pressures according to the weight of which is distributed across each axle of his/her vehicle. For example: If the gross vehicle weight of the vehicle is 25,000 pounds and the front axle is carrying 8,500 pounds of weight, the front tires are carrying 4,250 pounds per tire. If this were the case, each front tire would need inflated to 105 PSI as a single application.

The rear axle would then be carrying 16,500 pounds across the number tires on the vehicle (4). This would require each tire to be inflated with the same 110 PSI (16,500/4 = 4,125 pounds) in a dual application.

The pressures listed above are provided as a means of explaining how to configure inflation pressures within each tire and does not necessarily mean that you should use the inflation pressures provided within the example. Gross vehicle weights vary per vehicle and each owner MUST adjust tire inflation pressures according to your specific gross vehicle weight, axle weight distribution and application.

Please take into consideration, these 245/70R19.5 HSR1 products are rated for speeds up to 81 miles per hour. Exceeding the lawful speed limit is not recommended nor endorsed. Doing so would nullify any warranty or claim against these products and would jeopardize the safety of those within the vehicle.

Hope this helps!

Tamiko Diggs Martin
Continental Tire the Americas, LLC
Inside Sales Supervisor-Commercial Vehicle Tires
704-583-3904 direct dial
980-253-0839 mobile
704-583-4806 fax

I knew Continental was an established tire company but they are new to "RV" specific tires.  I guess they have had them but not marketed them to the RV market or is this a new tire for them? 

Hard to compare the two companies but here is what I could compare based on Goodyear info. tables.  Continental has additional info. lNoted difference:  The Tread Depth is lots deeper, the Overall Width slightly larger but the Outside diameter is smaller.  Do you see anything positive or negative - any red flags or yellow caution signs?

                                        Tread                            Meas.                                        Max Load at
Tire Size      Load  Side  Depth      Apprvd.        Rim      Overall    Outside      Infla. (PSI)
                  Range  wall  (32s)        Rim Widths    Width    Width    Diameter        Single

245/70R19.5 F        BL    13.5          6.75, 7.50    7.50      9.7          33.0          4080@95        Goodyear
245/70R19.5 G        BL    13.5          6.75, 7.50    7.50      9.7            33.0          4540@110    Goodyear
245/70R19.5 H        -      16            7.50, 6.75        -          9.8            32.9          4940@115    Contenintal

Now if I just knew what my wheel was rated for and if it could handle the higher load range??

I am so confused but still trying to figure this out.  Who knew buying tires could be so confusing??  All this started because I am trying to get an recent mfg. date and I can get late 09 or 10 mfg. date for the higher LRs.  The Goodyear LR F are all 2008 mfg. dates.

Jennifer

I knew Continental was an established tire company but they are new to "RV" specific tires.

Click to expand...

The HSR1 is not an RV specific tire - Continental designates it as a "Heavy Steering Regional" tire, which makes it suitable for the front wheels on any medium-heavy duty vehicle that uses those sizes and load range.

I think what you are seeing is that dealers are looking around for more cost effective answers to their customer's tire needs and have found that Continental, Bridgestone, Yokohama, Toyo, etc. are primed and ready to fill their needs. You get a major brand tire with full warranty at an attractive price from a company with a proven track record.

I do not doubt that the Continental tire would be good tire.  I am getting the same size tire but a higher load range.  It is the load range that has me concerned.  I need to fine or determine the max. wheel weight rating for QSHOUSE.    Wheel load rating requirements are determined by dividing the vehicle's heaviest gross axle weight rating (G.A.W.R.) by 2 if it not written on the wheel.  From what I am reading it is not recommended to get a higher Load Range tire then the wheel is rated for.  Maybe that warning is so one does not fill the tire to its max. PSI - which we would not do - and thus exceed the wheel load max. rating.  I have not found anywhere where they give a reason for the LR vs wheel load capacity.

More information need.  I am leaning toward the Load Range G by Goodyear G670.  I do not think that would be too far off but without knowing the wheel rating I am leary of the Continental LR H.

Please fell free to explain the error of my thinking as I am not an expert.  Just trying to learn before I get in over my head. 

Jennifer

It is not unusual for the wheel on a big coach to be rated at less than the max possible pressure for it's tires. You just have to observe the lower limit.  The wheel load limit is usually stamped on it, but may not be visible without dismounting the tire.  Do you know the brand and model of wheel?

My wheels are rated at 125 psi, which also happens to be the top pressure for my G670 295/80R22.5 tires.

Gary,

I am sorry to say I do not know the max. load limit or the max. PSI limit of our wheels -  and of course the wheels are hidden by wheel coveres.    Dan is planing to get the manuals out of storage tonight so maybe I can find something.  We do have a spare but I do not know if Dan is going under tonight.

We have the Ford F53 22,000 lbs. GVWR chassis.  Based on 2008 data looks like our front axle = 7500 lbs. and rear axle = 14500 lbs.  If the formula works: 
                  7500/2 = 3750 lbs each front wheel
                14500/4 = 3625 lbs each rear wheel

Hummm, If above true then we've been over inflating the tires and that is per GB recommendation.  Also there is not a good fit of one PSI = single, duel combo - which means that you have different PSI in the front tires vs. the rear tires. 

I also realize the tire PSI/weight tables do not go low enough.  On trip last year, the each rear tire carried 3155 lbs and front carried 3280 lbs. ... and the Goodyear table weights listed are all higher.

I'll get back with hopefully with more understanding and info. but I am beginning to realize that it really higher Load Range is OK. but the load range table will not go low enough for actual weight on tires. 

Hope to find good info. when Dan gets home.  Please wish me luck.

Jennifer

If your weights are less than the lowest shown in the table, then inflate to the minimum pressure shown plus 5psi.

A higher load range should let you run them at a lower pressure and give  a somewhat softer ride.

Click to expand...

That's not right, Ned.  Look at the load tables - for a given tire size the inflation pressure vs. load is the same regardless of the tire's Load Range.  The difference is the higher rated tire can be inflated further to handle heavier loads.

In other words, if the load is within the rating of an "F" range tire, going up to a "G" range won't let you lower the pressure.  The "G" rated tire will require the same pressure as the "F" at that load.

You're right, Lou, if the tires are the same size.  Generally, when going up a load range, you are also going up a size and that lets you run at a lower pressure for the same load.  My original G159 LR G tires required a minimum of 95psi for my axle weights but my G670 LR H tires can be run as low as 80psi for the same weights.

I think some (a lot?)of the confusion is my fault.  Georgie Boy recommended 85 PSI for our Goodyear G670 245/70R19.5 F tires manufactured in 2003 and that is the pressure Dan has been keeping the tires.  The 85 PSI is also the highest load for these tires and covers the load if the motorhome was loaded to the 22,000 lbs. GVWR of our chassis.  I perhaps erred thinking since we have never loaded the motorhome to 22,000 lbs. we could lower the pressure and adjust it to our actual load.  BUT the tables do not go low enough to cover us which is what Ned responded to.  In hind sight this is not a good practice and I have beat myself with a wet noodle. 

However in Feb. 2006 Goodyear changed the method of manufacture of the G670 245/70R19.5 tire and it increased the pressure from 85 PSI to 95 PSI for the same F load range.    Took some doing but finally got Dan to agree.  He is still contacting people but did get Ford and some other tire knowledgeable people to agree with the increase to 95 PSI for same F load rating.  The PSI/load range weights are consistent with small amount of weight difference between Goodyear and Continental tires.

Current thinking is if we get the G or H instead of the F load range tires we would use the 95 PSI for load range F.  The whole reason for getting the G or H load range is to get more current manufacturing dates as the Goodyear F load range tires are all 2008.

We still do not know what our wheels PSI rating is.  Dan did crawl under and look at the spare but no markings.  We ordered the missing Dicor tool required to remove the wheel covers and hopefully we will be able to find a PSI rating.  Wish us luck.

The one thing I have learned out of all this is one must look at the tire manufactures' load range chart.  Things change and your safety is riding on those tires.  I can see where it would have been easy for Dan to continue using 85 PSI for the new tires and thus under inflating them.

Jennifer

Tom, I concur with the last sentence in your comment about Michelin tires. My original statement about Michelin was not intending to "bad mouth Michelin", but only to provide information. However, after reading your comment I thought perhaps Michelin had changed it's policy. So, without intending to be argumentative, let me provide some more info.
Some years ago I took delivery of a Freightliner semi truck that came with 10 new Michelins. Within 5 months I lost 7 of the 10 tires, all from blow-outs on the sidewall. All of the seven Michelin dealers where the blow-outs occured, (in Texas, Colorado and New Mexico) informed me at the times that "there was no Michelin Warranty". ( I did complain after the seventh blow-out to Denver Freightliner, where I had bought the truck. Denver Freightliner, although the truck company does not warranty tires, did make it right with me.)
Since I have been a rancher since 1954 I have had and do own quite a number of tires of all types and makes. So I try to keep up with the latest info on equipment.
Last summer, at the Greeley, Colorado annual Farm Show, I discussed Michelin tires with the Michelin rep at the tire booth there. As of last summer, the Michelin tire rep there informed me that Michelin has never had a tire warranty. However, Just to see if Michelin has recently changed it's warranty policy, yesterday I called my farm tire dealer, TDS in Craig, Colorado. I was informed that TDS knows of no tire warranty by Michelin. Then, just to see if there might me a difference among dealers, I phoned the Wheatridge, Colorado TA Truckstop where I do business when in the Denver area with my semi. The Service Manager there infromed me that TA knows of no Warranty by Michelin for tires. The TA Service Manager gave me the phone number of the Michelin regional manager in Denver. I phoned the Denver regional Michelin Manager and was informed that Michelin has no warranty. However the manager informed me that on occasion, especially for fleet customers, when he is requested, he has in the past, and can at his discretion, make "adjustments" for tire problems involving Michelin tires. He stated that he will consider each case individually.

Will, could it be that Michelin has a different set of rules for large truck tires vs car tires?

Or a different policy for tires in commercial vs, non-commercial service?

Michelin does have a different policy for Commercial vs Consumer use use - says so right in their tire warranty booklet.  Page 2 lists the Commercial Long Haul coverage and page 3 the Consumer coverage. In a nutshell, RV tires are covered for 5 years or original tread life, which ever comes first. The identical tire used in commercial service will be limited to tread ware only - no 5 year limit. A designated Michelin long haul truck tire in Commercial Service will have a 700,000 mile, three-retread warranty.