Tires and Air Pressure

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Tiercel

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I took the MH out to top off the propane tank, add fuel stabilize and top the tank off, and put air in the tires.

I was a little surprised. I popped the rear hubcaps expecting to find a valve stem extension on the inside rear tires that extended through the rims of the outside rear tires. I didn't. The air hose chuck had a long tube/shank on it, and there was no way to get it at the correct angle to pressurize the inside rear tires. So next, I went to crank the air pressure up to 75 - 80 PSI, and the compressor only went as high as 70 PSI.

I have a three gal air compressor at home, but I wonder where most of you top your air off when on the road. My guess is truckstops.

I will be shopping for some valve stem extensions. Not sure if I can find them locally or if I will have to order online.
 
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RVRAC

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I used to have pancake compressor for some years. This year I bought on VIAIR compressor. The best thing I bought in years.
 

Tom55555

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If you put on extensions make sure you have metal tire stems and they are secured to the outer rim.

The first time I didn't and had to call AAA twice.
 

DonTom

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I have a three gal air compressor at home, but I wonder where most of you top your air off when on the road. My guess is truckstops.
If you did not pay more than $100.00 for your RV air compressor, you paid way too much!

Decent ones cost money. I carry a 120 VAC tankless in this RV that does the job well. But unfortunately, it's not made any more.

Don't waste your time with the 12 V compressors with RV tires that require more than 80 LBs. Always look at the CFM rating at ~90 psi to compare. Cheap ones will have no CFM rating.

-Don- Ashland, OR
 

Kirk

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I carry an 110 volt air compressor capable of 150 pounds.
If you have a generator to supply 120V power that is my recommendation as well, but before you buy one make sure that the pressure when the compressor starts is above the needed air pressure for your tires. Most of them start running at a pressure that is about 20# below the pressure where the compressor stops.
 

Tiercel

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Thanks! There is a lot of good advice here.

I notice no one suggested truck stops. Maybe truckers use onboard air compressors.
I certainly don't mind buying a good compact air compressor. The (1-more thing to haul) is more concern than cost but no big deal.

I guess I could use the valve stem extensions just to fill the inside tires then remove them if they stress the valve stems.
 

DonTom

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Most of them start running at a pressure that is about 20# below the pressure where the compressor stops.
Ones with a good CFM at 90 psi rating are often the opposite. Mine is an old Campbell Hausfeld tankless
that is rated 100 psi, but will easily do just above 110 psi.

-Don- Ashland, OR
 

Tiercel

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Btw, My valve stems are metal and look like they have a short extension on them that is fine for the outside tires.
 

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DonTom

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Those are 12 v wonders.
Yeah, there are a few decent ones that have to connect direct to the battery with the engine running, as they draw a lot of current at 13V. But I find it easier to just use a 120 VAC as most RV's have AC outlets on the outside, as well as a genny for use on the road.

-Don- Ashland, OR
 

Gary RV_Wizard

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Truck stops are a good choice if you don't want to carry a compressor, but many RVers like the convenience of being able to air up at their campsite before getting on the road. Of course, that's the RVers who actually pay attention to tire pressures. Too many do not, and they just drive on, blissfully oblivious until a tire fails or gets badly worn.

I'll disagree somewhat with Don concerning 12v compressors - there are some very capable ones available. Probably not the ones you see at Walmart or an auto parts store, though. And good ones are not cheap. You will also need a high-amperage extension cord and direct-to-battery connection - none of those puny auto-store cords that plug into a lighter socket.
Here a Viair that can deliver as much as 130 psi:
 
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DonTom

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You will also need a high-amperage extension cord and direct-to-battery connection -
Yeah, I guess I should have said the decent 12V ones are just too much hassle. We usually have AC outlets to use right on the outside of our RVs. Even this old Y2K RV. I just used it to charge up my electric motorcycle. 120 VAC compressors are much easier to setup and use.

-Don- Ashland, OR
 

Skookum

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At home I use an old air compressor (pancake style) with this attached to a long slinky air hose:

Milton Heavy Duty Tire Inflator

The dual head gets those valve stems on the duals that point the wrong way, and it fits through the holes on the alcoa's up front to get those valve stems.

The air compressor has to huff and puff to get me up to 95-100, but it does the job.

On the road I just use truck stops or gas stations with a nice open area for checking/filling tires. Most compressors don't have a problem going up to 100, at least, I haven't found one that doesn't...yet.
 

Tiercel

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That dual head was on the the compressor at “Sheetz” where I stopped yesterday. It was great for the outside rear tires with the valve pointing in but with the length of the dual head shaft there was no way to get the correct angle on the inside tires.

Since most of my trips will likely be short (I think) I will likely inflate good at home and use truck stops. If I get an air compressor it will likely be a Viair 12 volt. It gives me the option to use it whether I’m down to 1/3 tank of gas and the generator won’t start because of that or any other reason.
 

DonTom

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Since most of my trips will likely be short (I think) I will likely inflate good at home and use truck stops. If I get an air compressor it will likely be a Viair 12 volt. It gives me the option to use it whether I’m down to 1/3 tank of gas and the generator won’t start because of that or any other reason.
Sounds like another possible use for my 300 AH lith converter and 4KW inverter. But I usually fill up my RV at a half tank to avoid the generator issue.

-Don- Ashland, OR
 

Tom55555

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Thanks! There is a lot of good advice here.

I notice no one suggested truck stops. Maybe truckers use onboard air compressors.
I certainly don't mind buying a good compact air compressor. The (1-more thing to haul) is more concern than cost but no big deal.

I guess I could use the valve stem extensions just to fill the inside tires then remove them if they stress the valve stems.

Keep in mind that an air compressor won't help you if your stem breaks.
 

NCSU Dad

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When I was looking at my rear dual wheels I could only see the valve extensions for the inner dual wheels. When I pulled the outer wheels off to see what sort of extension I would need I found extensions were already installed. I'm guessing the centrifugal force of the tires rotating cause the extensions to move to a position where (a) I couldn't see them at first (b) Once I found them I couldn't get an air chuck on them no matter what in that position.

Online I see these black rubber looking things you install in the rim cutout with a hole in the center for installing the stem to stabilize it. Anyone use these?
 

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