Filling LT tires

[wrp75_CO]

I have yet another dumb new guy question: what do people use to fill air on tires that need to go above what "P" tires take? I have a small compressor that, while it claims to get up to 120 PSI, is currently letting out more air than gets in. Do you have to go to the gas station/truck stop air machines?

Thanks!

 

[dchrist1733]

I have a small Craftsman air compressor that I use and it works fine, even to fill my G tires on the trailer. Are you sure the chuck you are using to fill the tires is not leaking. I had to replace mine because it would not fill the tires. I bough a heavier one and that works much better.

 

[TucsonJim]

My "pancake" compressor will deliver about 140psi. If you have an adjustment on your compressor, make sure you max it out.

 

[ACDW-Ottawa]

Anyone know of a good small 12V air compressor rated at more than 110PSI with high CF

Be careful using the air compressors at the Flying J Truck Stops. I have had trouble at several stations trying to fill my Goodyear high pressure tires @ 110PSI. I have lost more than an hour several times because their compressors were either not working or set too low (apparently most truck tires are around 50-80 PSI). The result was that the pressure was reduced so low that I could not drive on them before getting the pressure back up. I had to resort to my little compressor I carry that takes forever to fill those tires and left with the same pressure I arrived with, 100PSI - arrgh.

In addition to good quality air chucks, you need a good compressor with high CFM (Cubic feet per minute) and high duty cycle (time it's allowed to run before cooling down).

It's not enough that the compressor is rated to 150PSI because the duty cycle will not let it run long enough to fill even one tire and certainly not two tires. You need high CFM to get the large volume of air to fill those large tires at high pressure.

If it's a large 120VAC compressor, you need one with large tanks to provide the necessary volume of air to fill those large tires especially for low CFM compressors.

Anyone know of a good small 12V air compressor rated at more than 110PSI with high CFM and duty cycle? Preferably, one that I could mount on my truck hard wired to my battery.

Thanks

 

[notsosan]

I never had much luck with 12V compressors until I bought a Viair 400P 12V rated for 150 PSI. I don't know how well it would do at higher pressures but it will take one of my truck tires from 45 PSI to 80 PSI in 3 minutes so the 33% duty cycle is more than enough for me. They also make a 450P model that has a 100% duty cycle. Viairs aren't cheap and draw a lot of power but they are well made and really do the job.