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lylefikse

Tire inflation

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Just purchased a new motorhome and getting ready to start out on our first long trip.  Trying to get tire inflation right after loading it up.  Michelin tire chart shows duel or single tire.  We have duels with a tag.  That isn't on the chart.  How do we figure tire pressure with a tag?

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If the tag axle has just one tire on each side, use the weight shown for single tires.  Only when there are two tires on each side would you use the duel chart.  Those pressures shown are minimum for the weight on each set (corner) but you'd always use the same pressure on both sides of an axle.  Start by having the MH weighed at a location that can give you the weight on each corner or set of tires.  The duals should be weighed separately from the tag. 

I'm not a fan of Michelin tires but they publish a guide for RVers that good to read over.  Here's link to that document:
https://michelinb2b.com/wps/b2bcontent/PDF/RV_Tires_Brochure.pdf

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I'll be weighing tonight.  I thought I only needed to weigh each corner.  My tag is a single tire on each side behind the duels.  Don't think the scale I will be using will allow me to weigh the duels separate from the tag. Don't think I can get the front tires off the scale to weigh the duels alone. I could weigh the tag separately.

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18 hours ago, WILDEBILL308 said:

What is the weight on your tags? Is it a duel or single wheel tag?

Bill

Do they have class A's with dual tags?  I've only seen one tire on most RV tag axles.

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Not sure where you are weighing.  The best way is to get the four corner weight then consult the tire charts.

I've weighed twice in the past several months, once without my toad (24' enclosed trailer) and once with.  This was my weights without the toad:

Steer:  13,660

Drive:  22,020

Tag:  2,860

I looked at the charts, considered my weights from weighing with my trailer attached, and I am running 105 cold psi in my steer axle tires, 100 cold psi in my drive duals, and 95 cold psi in my single tag tires.

Our coaches are similar but yours may be heavier, not sure.  If you have a Spartan chassis it could be heavier but then again we are loaded for full time travel so who knows.  Hope this helps, safe travels.

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Michelin 365 70R 22.5 fronts.   Front driver 8820.  Front Pass 8960. Front total 18,000  I believe Michelin chart shows 105 PSI for front.

Michelin 315 80R 22.5 rear,  Rear driver 13,000 (including tag) just tag rear driver 4720.   Rear Pass 11680 (including tag) just pass tag 4640.  Rear total including tags 26200.

Total weight 44,360.

I believe that would be 100 PSI in all rear tires. 

Your input is appreciated.

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54 minutes ago, lylefikse said:

Michelin 365 70R 22.5 fronts.   Front driver 8820.  Front Pass 8960. Front total 18,000  I believe Michelin chart shows 105 PSI for front.

Michelin 315 80R 22.5 rear,  Rear driver 13,000 (including tag) just tag rear driver 4720.   Rear Pass 11680 (including tag) just pass tag 4640.  Rear total including tags 26200.

Total weight 44,360.

I believe that would be 100 PSI in all rear tires. 

Your input is appreciated.

Just keep in mind that those are MINIMUM preshure. I would add at least 10%  for a safety cushion.

Bill

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Agree with WBill.

Joe S.

Koni by Renegade, has dual on tag & drive!  Next year, you'll have your choice of current set up, or single drive & tag!  Prevost by Volvo is considering the same! 

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3 hours ago, manholt said:

Agree with WBill.

Joe S.

Koni by Renegade, has dual on tag & drive!  Next year, you'll have your choice of current set up, or single drive & tag!  Prevost by Volvo is considering the same! 

I doubt my Newmar model will every have a dual tag Carl, it is a turning tag so that wouldn't work too well.  I'm guessing these turning tags are so popular that they would never change that configuration, or at least I hope not.

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13 hours ago, lylefikse said:

Michelin 365 70R 22.5 fronts.   Front driver 8820.  Front Pass 8960. Front total 18,000  I believe Michelin chart shows 105 PSI for front.

Michelin 315 80R 22.5 rear,  Rear driver 13,000 (including tag) just tag rear driver 4720.   Rear Pass 11680 (including tag) just pass tag 4640.  Rear total including tags 26200.

Total weight 44,360.

I believe that would be 100 PSI in all rear tires. 

Your input is appreciated.

I was running a little more in my steer axle tires than the chart called for.  Not sure if you have the Spartan or Freightliner chassis.  My FL chassis rode a little rough in the front so I reduced the psi on the steer axle closer to chart.  If you are on a Spartan chassis it probably rides pretty good with closer to 110psi in those front tires would be my guess.

Do you have, or are you considering a TPMS (tire pressure monitoring system)?

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You should at least be able to get the tag load separate from the drive duals with a second weigh after pulling forward so only the tag is on the scale.

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315/80R on Front, with my 7% +/- I run with 110 psi!  295/80R Drive & Tag = 105 psi!  Works for me! :D Spartan K2 chassis.

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No.  The pressure of the entire axle should be divided by 2 and then compared with the charts.  The best way to weigh the axle is to weigh each tire individually and then adjust the pressure in both tires to the highest pressure shown in the charts for the heaviest side.  The recommendations I've seen and heard say that side to side, the pressures should be the same.

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Each set of dual tires on drive axle, each on tag & steering...if you go to a portable scale, such as Escapees or DPS.  CAT scale will give you steer, drive & tag if it's long enough. Not individual.

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16 hours ago, manholt said:

Each set of dual tires on drive axle, each on tag & steering...if you go to a portable scale, such as Escapees or DPS.  CAT scale will give you steer, drive & tag if it's long enough. Not individual.

Escapees Smart Weigh will give the weight on each individual tire or tire pair with duallies.

Ken

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On 9/29/2018 at 10:01 PM, lylefikse said:

Tireman9   I did give separate tag weights.  Shouldn't the tag have the same pressure as the duels?

Sorry been busy traveling for work ( 2 trips to CA + MIA + KY  in 16 days) 

The number of tires at the end of an axle establishes single (1) or Dual (2) when reading tire charts.

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