WOW-Check your tire pressures!

[JRMEDPHYS]

Don't believe the hype about nitrogen! That is a huge crock of BS! I am a physicist and nitrogen in your tires does not change the laws of physics.

Atomic size? What a farce!

Pressure changes with temperature on any gas including good old fashioned AIR according to the ideal gas law.

There is way too much anal retentiveness about tire pressures on this forum. Use common sense folks and all will be well!!!

[Dr4Film]

CIP or Cold Inflation Pressure is measured on the morning BEFORE you leave on your day's drive.

That should be set to your AIM psi based on your weight and tire inflation tables from the manufacture of your specific brand of tires.

Extreme cold or hot temperatures will change the required CIP dramatically. Always set your CIP early in the morning BEFORE the sun gets to heat up the tire.

Altitude can also make a different BUT only if you plan to remain at that same altitude for a considerable length of time.

Your TMPS should be set for your baseline CIP. That aim should never change. It's the tire CIP that needs to change depending on ambient conditions.

Dr4Film ----- Richard

[spinn]

Originally Posted by JRMEDPHYS

Don't believe the hype about nitrogen! That is a huge crock of BS! I am a physicist and nitrogen in your tires does not change the laws of physics.

Atomic size? What a farce!

Pressure changes with temperature on any gas including good old fashioned AIR according to the ideal gas law.

There is way too much anal retentiveness about tire pressures on this forum. Use common sense folks and all will be well!!!

JR I am with you, although not as emphatically as you, regarding using nitrogen in rv tires, it's generally overkill. There is one point, however, that I would offer for your consideration. Nitrogen systems usually deliver DRY gas while compressed air is often laden with water vapor which can (not will) negatively effect the inside of the tie and wheel. I live in a very humid climate so I use a water separator and a coalescing filter on my compressor. This too is probably overkill but it makes me feel better!
Steve

[Crasher]

I talked myself into deflating and filling the tires on our motorhome with nitrogen. What a joke that was. I was leaving WI in 30* weather and traveling to 80* and 3000' altitude change in 4 days. I was concerned about the pressure change because they had to be close to the max allowed for the steering tires. I saw virtually no change in the pressure changes using nitrogen vs air from a compressor. Now, I am able to take some weight off the steering axle by regulating the tag suspension pressure. The steers require 110 psi so I run 115. I run 100 psi in the drives which is 15# more than required and 90 in the tag, also 15# more than needed. With this setup, the fronts might be down to 110 on a cold day or up to 120 on a hot day at higher altitudes. They are always within the recommended min range and at or below the max. I just get in, check the TPMS for any one being way off and drive. According to a Michelin rep it really doesn't matter what the pressures get up to while on the road as long as the cold psi is where it should be. I haven't had to change anything in 5000 miles of driving in any temp and up to 11,000' altitude.

[Lincolnboy2]

Originally Posted by Dr4Film

CIP or Cold Inflation Pressure is measured on the morning BEFORE you leave on your day's drive.

That should be set to your AIM psi based on your weight and tire inflation tables from the manufacture of your specific brand of tires.

Extreme cold or hot temperatures will change the required CIP dramatically. Always set your CIP early in the morning BEFORE the sun gets to heat up the tire.

Altitude can also make a different BUT only if you plan to remain at that same altitude for a considerable length of time.

Your TMPS should be set for your baseline CIP. That aim should never change. It's the tire CIP that needs to change depending on ambient conditions.

Dr4Film ----- Richard

Thanks Richard, I agree. I am not traveling, was just curious about the pressures and glanced at them last weekend.

Other posts love flying on the runaway freight train across Lake Conclusion I see, as usual when dealing with tires.

No obsessing over it, but the question was acutely and clearly answered by several folks, in that the lower pressures are not damaging structurally to the tires, they are well withing tolerances of the tires, and, as other pointed out, you can't go chasing temps across the country either.

When I get ready to travel, I'll check and adjust then.

[Lincolnboy2]

Originally Posted by djbmsu

Why would you run the engine if your not going to use the coach? all you are doing is creating moisture from the heat then letting it sweat and freeze and a bazillion other things that will cause problems.

Really? Where do you come up with that?

Sorry, but its good for the engine, seals, lubricants, belts, hoses, on and on and on when you start and run the engine (till all fluids get to normal temp-for me about 15 minutes) at least once a month. I treat my fuel with Sta Bil at the beginning of the winter season as well.

The generator as well, at least half load for 15-20 minutes every month.

I have not driven the coach since the first week of December, but also believe it is good to drive the coach at least every 2-3 months to help keep the tires nourished by getting them up to temp/speed for 20-30 miles.


I also believe its good to check and use the plumbing system monthly too, but unfortunately KC is winterized and I blew out all the lines/dumped the tanks and put the pink antifreeze in the p-traps and tanks for good measure, which I'm glad I did since we had temps in the mid teens this past week.

So you are telling me I am creating a bazillion other problems by starting and running my chassis engine once a month? I'm sorry, I don't see how.

[JC2]

Originally Posted by JRMEDPHYS

Don't believe the hype about nitrogen! That is a huge crock of BS! I am a physicist and nitrogen in your tires does not change the laws of physics.

Atomic size? What a farce!

Pressure changes with temperature on any gas including good old fashioned AIR according to the ideal gas law.

There is way too much anal retentiveness about tire pressures on this forum. Use common sense folks and all will be well!!!

[Tomtall]

Don't believe the hype about nitrogen! That is a huge crock of BS! I am a physicist and nitrogen in your tires does not change the laws of physics.

That's why I posted the link so people could see that.

[Cooperhawk]

As I said the Nitrogen thing was not my doing. I wouldn't have spent the money.

I too think that it's a good idea to start the engine every month or so and let the lubricants distribute themselves. Back on the farm I have seen engines that actually seized up from sitting idle for too long. The oil seeps off the cylinder and condensation sets in causing rust. Seals do dry out in time as well.

It has been way below zero here lately and I will not start the engine till it actually warms up a bit. I do think cold starting isn't especially good so I will wait, but if we wanted to head out tomorrow I would have no qualms starting it up right now.

It seems to me that we worry too much about our big toys. Probably over protect them. Oh well, what else is there to do.

[Wayne M]

The key to starting the engine is to let it run until it is up to operating temperature. If you don't you risk condensation forming, so I have been told.

[Rockman1]

I have a question about tires. While traveling down the highway I notice a lot of alligators I think they call them. I also notice a lot of them seem to have a lot of tread left. Why do so many tires go bad, wrong air pressure, objects in the road? Or?????

[Dr4Film]

Those "Gators" are from commercial truck tires that had been recapped. Since that piece of tire was "welded" onto the case quite often they don't last as long as a brand new truck tire does.

Heat is the number one enemy of tires.

Dr4Film ----- Richard

[Tha_Rooster]

I believe in checking tire pressure before every trip it's only your life. That way it doesn't matter if it's cold or hot outside adjust your pressure. It only takes but a few minutes.

[Barbaraok]

Originally Posted by Lincolnboy2

Really? Where do you come up with that?

Sorry, but its good for the engine, seals, lubricants, belts, hoses, on and on and on when you start and run the engine (till all fluids get to normal temp-for me about 15 minutes) at least once a month. I treat my fuel with Sta Bil at the beginning of the winter season as well.

The generator as well, at least half load for 15-20 minutes every month.

I have not driven the coach since the first week of December, but also believe it is good to drive the coach at least every 2-3 months to help keep the tires nourished by getting them up to temp/speed for 20-30 miles.


I also believe its good to check and use the plumbing system monthly too, but unfortunately KC is winterized and I blew out all the lines/dumped the tanks and put the pink antifreeze in the p-traps and tanks for good measure, which I'm glad I did since we had temps in the mid teens this past week.

So you are telling me I am creating a bazillion other problems by starting and running my chassis engine once a month? I'm sorry, I don't see how.

Yes, that what is correct. Do you see farmers running out to turn over their diesels each month? You do far more harm than good. Fill it with fuel, shut down, and don't start until you can run down the highway for 20 minutes or more. You can't get everything lubricated, etc., if she isn't moving. And unless the power at the park goes down, we don't start our diesel generator either during the winter while we are parked.