Tire pressures and my air compressor

What is the CFM of the compressor?

Kind of shocked that you have to carry that much pressure.

What tires and what wheel/axle weights???

Been called a brick by my wife before and not in a nice way either.....

The CFM of your compressor will determine how long it takes to fill a tire. A low CFM means you might have to shave and shower between tire fills.

Whatever the CFM is, get a pressure regulator and set it for the desired pressure and install that between the compressor and the air chuck. That will get you close without having to 'babysit' the process.

You sure about those pressures? Even commercial truck radials only fill to 105 psi.

wolfe10 wrote:
Kind of shocked that you have to carry that much pressure.

What tires and what wheel/axle weights???

Yes 130 sounds high.

If it is a small compressor with a small tank it will take awhile as compared to a tire shop compressor with a huge tank with lots of volume. Most of the large compressors of that size won't go higher than 150 lbs.

HighwayJunky wrote:
Ok, so granted I am not the heaviest brick in the load so thought I'd ask this question. It might be simple logic but I want to be sure. My RV tires are to be at 130PSI front and 120PSI rear.

My air compressor states that it has a maximum pressure or 150PSI tank pressure. So,if this is running properly it should fill the tires to their respective pressures. Right? Should I assume that since the tire pressure is to be 130 and the max pressure from the compressor is 150 then the amount added is only 20PSI and it a very slow rate??

Or should I get a higher PSI capacity air compressor to do the job?

I carry a small compressor rated at 150 psi and I doubt I could fill a tire to 130 psi. I carry 120 psi in my steer tires and it seems like it wouldn't go much beyond that. But I agree with others 130 seems too high. Have you weighed the coach yet?

slickest1 wrote:

wolfe10 wrote:
Kind of shocked that you have to carry that much pressure.

What tires and what wheel/axle weights???

Yes 130 sounds high.

If it is a small compressor with a small tank it will take awhile as compared to a tire shop compressor with a huge tank with lots of volume. Most of the large compressors of that size won't go higher than 150 lbs.

My shop compressor 7.5 horse vertical was factory set at 175 psi. It's 30 CFM at 175. I backed it down to 135 because that is plenty for any air tool. Air tools work on volume (CFM) not pressure.

Think I'd have a look at the recommended maximum COLD inflation pressure listed on the tire sidewall.

HighwayJunky wrote:
Ok, so granted I am not the heaviest brick in the load so thought I'd ask this question. It might be simple logic but I want to be sure. My RV tires are to be at 130PSI front and 120PSI rear.

My air compressor states that it has a maximum pressure or 150PSI tank pressure. So,if this is running properly it should fill the tires to their respective pressures. Right? Should I assume that since the tire pressure is to be 130 and the max pressure from the compressor is 150 then the amount added is only 20PSI and it a very slow rate??

Or should I get a higher PSI capacity air compressor to do the job?

Are you certain the required pressure is a 130 psi/

ours is only 120 PSI and my compressor will not do it.

130 is about the tire pressure limit for that compressor but my 150 PSI job hits 115 just fine.. May take a while to hit 130.. but yes, it should do it.

NOTE: Make sure there NO air leaks, many Quick Disconnects leak a bit and even the smallest leak at those pressures can be enough to cancell success.

I would get that Newmar weighed and then check the tire manufactures site for the proper air pressure for the weight. Never fill to max pressure on tire sidewall, it will ride like a brick and will wear the center of the tires down in no time.

1995brave wrote:
I would get that Newmar weighed and then check the tire manufactures site for the proper air pressure for the weight. Never fill to max pressure on tire sidewall, it will ride like a brick and will wear the center of the tires down in no time.

The maximum pressure listed on the sidewall is for loading at the rated load for the tire, First thing is to weigh the coach, full of fuel, water, propane and all your 'stuff' on board and then determine gross weight and adjust tire pressures accordingly.

I disagree with your premise that the center of the tire will wear down in no time or the unit will ride like a brick. Tires are designed to run at maximum listed sidewall pressure and tires provide very little compliance (flex) when rolling. The suspension provides ride compliance (comfort) not the tires. Tires are designed to carry a load with minimal flex (which causes internal heat), not provide a comfortable ride.