Filling Tires

[jlazar]

I have a gas motorhome so I am planning on carrying a 150 psi Porter Cable pancake compressor so I can check tire pressure in the morning when cold and fill immediately if necessary.  I would appreciate any thoughts if there is a better approach.  Also, any recommendations on a good brand of dual head tool to fit at the end of the air hose for inflating.  Thanks

 

[Gary RV_Wizard]

It sort of depends on how much air pressure the coach tires need. If less than 100 psi, you can probably get away with a smaller compressor, even a tankless model. Takes up a lot less space.

 

[jlazar]

I am fairly new to this.  At Vogt RV they said to keep pressure at 100 psi.  I have not had a chance to get it weighed yet.  The tires are new Toyo 22.5 and call for 110 max.  I was thinking the 150 psi because I have seen videos online about some compressor having trouble filling tires in the 95-105 range.  They said they don't have the power and you actually deflate rather than inflate. 

Do you recommend using a separate tire gauge or one that allows you to fill and read pressure at the same time?

 

[V2Neal]

Nothing to offer on the compressor, but I am a huge fan of separate fill attachment and tire guage. Yeah, more things to have on hand, but I haven't had the best of luck with the accuracy of the all-in-one filler and guages.

 

[SargeW]

All good advice. I would recommend a good tire pressure monitoring system as well.  There are several good products out there.  With a TPMS system on, it really takes the work out of keeping an eye on your tires.  And it may save serious damage to your RV, or even injury if you have a blowout.  It is really the smartest $300 +/- you will spend on your RV. 

 

[pixurit]

I consider this (http://www.portercable.com/products/ProductDetail.aspx?ProductID=23677) 150 PSI Porter Cable compressor a necessary part of my motorhome tool kit.  I've fitted a standard quick connect air fitting to the coiled hose.  It doesn't have quite the CFM of the pancake model but is much easier to store.  I haven't been able to find a smaller compressor that is capable of topping up even the 80PSI in my 19.5 tires.  Like the OP, I check tire pressures while cold.  I've always believed that if you drive more than a mile, you must wait at least an hour for the tires to cool before checking pressure.  Really can't see myself parking at a gas station for that long in order to check my tires.

I always carry both a dual head tire chuck and one of the simple single head models.  A good quality tire pressure gauge rounds out my tire pressure kit.  I've tried a quality tire chuck/pressure gauge combo and found that both the gauge's accuracy and the tire chuck's versatility were lacking.

 

[billwild]

Although a good idea, I have had not success with the tire gauges that let you fill at the same time as reading their large gauge. I have gone through two of them now. One blew apart, and the other even though it has a small lever that is supposed to hold onto the valve stem while filling, just blows off from the higher pressures needed. The plaque behind the drivers seat says 115 lbs in the front tires, I put in 108 and the steering and ride are much better. Now I just use one of those large truck tire pressure gauges and works well.

 

[jlazar]

Thanks for your help.  I will definitely go with individual pressure gauges/fill attachments.  I looked at the link for the Porter Cable.  I am concerned that the specs show it as a 150 psi tank but only rated at 90 psi.  I don't want to spend around $100 and not be able to fill my tires that call for 100 psi.  Again, I am new to this.  Do most campgrounds have an air pump available for you to use?  I guess what I am asking is do I need to carry the capability or will it be available at most campgrounds before I have driven enough to heat the tires?

I am guessing that RV tires are different than car tires where you can measure hot but they only go up 3-5 lbs.  How much of a difference could you expect in a 22.5 tire between cold (at 100 psi) and say running in 90 degree weather?

 

[Ned]

You won't find many, if any, campgrounds that have air compressors available.  Either carry a compressor or use truck stops for compressed air.  A 22.5" tire can go up 10-15psi when driving, especially in hot weather.  Our normal pressure is about 90psi and it's not unusual to see 105+psi on a hot day on the sunny side of the coach.  It's not a problem for the tires.

 

[jlazar]

Thanks.  My next step is to get our coach weighed.  The label from workhorse calls for 100 psi in front and 95 in the duals.  That label was created before sending to Tiffin for build.  So I am really interested in getting it weighed and checking the weight tables and psi based on those results.  Appreciate all the help on this.

 

[TomHaycraft]

Based on other's recommendations, just last weekend I purchased Porter Cable's 6-gal pancake compressor from Home Depot (http://www.portercable.com/products/ProductDetail.aspx?ProductID=17019).  I didn't time how long it took to fill the tank, but it finished before I could get the quick disconnects on the new hose I bought.  I only need to get to 50 psi for my trailer tires, but also purchased it to blow out the lines between camping trips this winter.  32 lbs, reasonable size, have room for it, could use some more pin weight anyway!

 

[BernieD]

Thanks.  My next step is to get our coach weighed.  The label from workhorse calls for 100 psi in front and 95 in the duals.  That label was created before sending to Tiffin for build.  So I am really interested in getting it weighed and checking the weight tables and psi based on those results.  Appreciate all the help on this.

Congratulations, you are recognizing the meaning of those labels and going about it the right way. The chassis label provides the PSI to support the GAWR. If your actual axle weight is less, you don't need the higher PSI. You'll get a better ride, better tire wear and better handling with the weight adjusted pressures.

 

[jlazar]

Went out for our first short trip today.  Checked the air pressure this morning.  The front tires were 93 and 96.  Upped both to 100.  On the duals, the inside tires were about 101 and the outside tires were 105 and 107.  Set all to 100.

Could not believe the difference in ride.  Much smoother and more stable.  Less impact by passing 18 wheelers.

Used my Porter Cable 6lb pancake with 150 psi.  Worked great when I let the pressure get up to 120.  When I tried inflating when the pressure was only 100, I actually was loosing air from the tire.

I am traveling with the pancake and plan to get the coach weighed upon return from this trip.

 

[FastEagle]

Went out for our first short trip today.  Checked the air pressure this morning.  The front tires were 93 and 96.  Upped both to 100.  On the duals, the inside tires were about 101 and the outside tires were 105 and 107.  Set all to 100.

Could not believe the difference in ride.  Much smoother and more stable.  Less impact by passing 18 wheelers.

Used my Porter Cable 6lb pancake with 150 psi.  Worked great when I let the pressure get up to 120.  When I tried inflating when the pressure was only 100, I actually was loosing air from the tire.

I am traveling with the pancake and plan to get the coach weighed upon return from this trip.

Toyo does not support or condone the use of load inflation tables/charts on their RV tires.

They support the DOT regulations. In the link provided below you will find all the information needed to service your Toyo tires as recommended by the manufacturer.

http://cache.toyotires.com/sites/default/files/RV_tire_safety.pdf

FastEagle

 

[SargeW]

Interesting article.  Good info for me, because now I will never own a Toyo tire.  If I had to run the maximum label pressure on the tires on my rig, the ride would be HORRIBLE.  Bouncy, rough, and excessive steering wander. 

And their asserting that you need to run max pressure because when the tires loses pressure naturally, you will have more time before the tire get dangerous.  What?  Since NO ONE can guess a tires air pressure by looking at it, the only way to check pressure is with a tire gauge, or TPMS. 

It sounds more like a lawyer safety statement. 

 

[Larry N.]

An interesting twist, with Toyo. To sort of echo Sarge, a number of years ago I had my oil changed on my 4WD pickup, but there was new management (unknown to me), and when I left they'd filled the tires to the max on the sidewalls. It was snowing lightly at the time, and I had waaaaay less traction than I expected, so went back (a block or so) to get the pressure down. I had quite an argument with the manager of the place, who claimed that max was actually what you were supposed to always run. Needless to say, they lost my future business.

It was actually unsafe (slip and slide) to drive on that light snow with max, and was almost (not quite) like dry pavement with the tires at my normal 35 psi. All this is disregarding ride, which is also worse at high pressure, and tire wear which would have worn out the center tread well before the tread on the edges.

 

[jlazar]

I understand what Toyo is saying about the DOT label.  But they also provide load and inflation tables on their website:  http://toyotires.com/tires/application-technical-data

 

[FastEagle]

I understand what Toyo is saying about the DOT label.  But they also provide load and inflation tables on their website:  http://toyotires.com/tires/application-technical-data

Tire load inflation charts/tables are a necessary tool in the tire industry. All retailers/installers have them to assist them in selecting tires with the proper fitment for your vehicle. They are necessary for making plus seized tire selections.

The only place tire load inflation charts could be found - maybe 35 years ago - would have been at a tire dealers store. The internet has changed all of that.

FastEagle

 

[FastEagle]

Interesting article.  Good info for me, because now I will never own a Toyo tire.  If I had to run the maximum label pressure on the tires on my rig, the ride would be HORRIBLE.  Bouncy, rough, and excessive steering wander. 

And their asserting that you need to run max pressure because when the tires loses pressure naturally, you will have more time before the tire get dangerous.  What?  Since NO ONE can guess a tires air pressure by looking at it, the only way to check pressure is with a tire gauge, or TPMS. 

It sounds more like a lawyer safety statement.

SargeW, They are saying to use the manufacturers recommended tire pressures found on the certification label, not the maximum pressure found on the tire.

I've never found a statement about any tires that would allow using less tire pressure than the vehicle manufacturer's recommended pressures. There are always special circumstances that might require temporary lowering of tire pressure but what would that be for a MH? The vehicle owner's manual will have tire pressures for temporary conditions.

FastEagle

 

[jlazar]

FastEagle.  I am not the original owner of this RV.  I have not been able to find a label on the vehicle from Tiffin.  I do have the orginal label from Workhorse showing completion of the chassis.  That label provides the front and rear weight capacities and tire pressures.  I was going to get the vehicle weighed to make sure I was not overweight, am evenly loaded AND to compare the weights to the workhorse label.  The workhorse label calls form 100 front and 95 on the duals.  The tire max is 110.  I am not looking to go below 100 for the front or 95 for the duals in any case.  What I was contemplating was using the tables from the TOYO sight to determine (based on actual weight) if I should move up from 100 towards 110 max for the front and from 95 towards 110 in the duals.  Is this a wrong approach and should I just stay with 100 and 95 regardless of weight?  Seems to be different from what I am hearing all other users are doing?  Is the workhorse label something that Tiffin has to work within when building the motorhome?  I apologize for being so long in this question.