Community Forums

tompen · 01-13-2013, 02:15 PM

This has probably been beat to death, but, what do you use as your rule for tire pressures. The tires say max cold 95 PSI. I know what this means. Do you run them at max cold, or a little under. 225x19.5 radial tires. Dual rear. I don't have a book for the coach and the workhorse manual says to refer to the chart. I can't find one.
Thanks
Tom

palehorse89 · 01-13-2013, 02:22 PM

Hello, do a search on here about "tire pressure" and you will be able to read to your heart's content. You have to know the weight on the tires and then go by the mfg. tire pressure charts. What kind of tires do you have?

sdennislee · 01-13-2013, 02:25 PM

Tire pressure should be based on loaded weight of the coach. Once the weight is known you can then compare that weight to the tire manufacturer's chart. Charts are usually available on line from the manufacturer.

Corner weights are best but axel weights will do.

Only rule of thumb I am aware of is that its better to run higher (without exceeding max pressure) rather than lower as you will damage the sidewall if under inflated for the loaded weight

wildtoad · 01-13-2013, 02:49 PM

Quote:

Originally Posted by tompen

This has probably been beat to death, but, what do you use as your rule for tire pressures. The tires say max cold 95 PSI. I know what this means. Do you run them at max cold, or a little under. 225x19.5 radial tires. Dual rear. I don't have a book for the coach and the workhorse manual says to refer to the chart. I can't find one.
Thanks
Tom

Somewhere in the coach you should find a piece of paper perhaps glued inside a closet. (Mine is just under the driver side window) It should show the GVWR, GAWR and the tire pressures based on these numbers. These numbers are the ones to be used. Having said that, the best plan is to get your unit weighed, then use those numbers along with a chart from your tire manufacturer and come up with the proper pressure.

Alan_Hepburn · 01-13-2013, 03:53 PM

Quote:

Originally Posted by tompen

The tires say max cold 95 PSI. I know what this means.

Not quite enough information here, but I can say with good confidence that your tires do NOT say "max cold 95psi". If they happen to be Goodyears, for instance, in 225/70R19.5 Load Range F then they say "Max Load (Dual) 3415 lbs at 95 psi Max" (or close to that). What that means is that if the tire is inflated to 95 psi then it can safely support 3415 lbs in a dual wheel configuration. If you exceed that weight, or inflation, then the tire is not guaranteed to hold up. If you lower the pressure to 90 psi then it can only safely carry 3245 lbs in a dual configuration; at 85 psi it can safely carry 3115 lbs in a dual configuration.

What does this all mean? Basically, in order to know how much air your tires need you need to know how much weight they are carrying.

micd · 01-13-2013, 04:17 PM

You are looking for the tire pressure chart for your tires.

Here is a nice tutorial from Goodyear. You can download their charts here also.
The Inflation Loading - Goodyear RV

Here is Michelin's.
Michelin North America RV Load & Inflation Tables

Here is the one for my Hankook AH11s.
1994 Brave 29RQ RV: Tire pressure chart for our Hankook AH11s

tompen · 01-13-2013, 04:38 PM

Thanks folks. I get the weight/pressure thing. Just no way I can get it weighed before heading out. There is a chart in a cupboard giving the gross weight etc, but nothing about tire pressures. I have to get some flexible extensions for the inside duals and then I will wing it. I'll see how it rides and handles at 85psi. Thanks again.
Tom

Gadget63 · 01-13-2013, 04:43 PM

In my Bounder there is a chart in my bedroom stating recommended pressure. I am well below the weight limits and I drive at the recommended settings of 95 cold for the fronts and 85 cold for the duelies.

tompen · 01-13-2013, 07:24 PM

Thanks Gadget
I'll keep looking for that chart. Near as I can tell I will be about 16,000 lbs. Maybe 95 in front is a good starting point. Lot easier to drop them down on the road than add air.
Tom

Gadget63 · 01-13-2013, 08:32 PM

Tom I bought a tire pressure monitoring system and I feel safer knowing tire pressure and temperature at a glance. And, in my opinion I'd rather run higher then lower, lower gets you in trouble with overheating and blowouts.
p.s.
I have an 08 softtail classic... love that bike!

tompen · 01-14-2013, 07:14 AM

I worked in the office at an independant big truck shop for a few years after I retired. He was an old friend and needed a little help straightening out his office. I'm going to run over there this morning and talk about a monitering system. I didn't remember how much those tires cost.
My entertainment for a few years was a new Harley every 2 years and my Toy Hauler. I bought the Spyder to ride 2 up and love it. The touring bikes are too high for me to be comfortable on now. The Softail is perfect.

RickO · 01-14-2013, 07:29 AM

Without knowing the weight of the rig, I would go with what's stamped on the sidewall. It'll probably ride rough until you can get it weighed and back off the PSI a bit.

Rick

tompen · 01-14-2013, 07:51 AM

Thanks Rick
Thats kind of the info I was looking for. I always tend to keep under the PSI on the tire. I learned that trailer tires should be run at that pressure. Made a big difference on my Toy Hauler. I moved the pressure from 70 to 85 PSI and it towed much better. Not too old to learn from experienced folks.
Tom