The Question That Seems to NEVER BE ANSWERED!

[camper94]

I have installed brand new Sailun 17.5 H Tires on my Pride and Joy Redwood 38RL.

Now, I have always run a TPMS to keep track of all my tires, both on the tow vehicle and the RV.

I would love to know what is an acceptable increase in Tire Pressure after the Tires warm up while traveling.

The Sailuns are a 125psi Cold Tire Pressure, which is where I have them set.

Naturally the tire pressure will increase as you go down the road. On a short trip this weekend, I was seeing pressures around 135 to 140 psi and I think that is acceptable.

I've been told by experts (BIG QUESTION MARK) that an increase of up to 15 percent of your cold tire pressure is acceptable.

I wish I could find a good answer on this matter and I have searched hi and low for the information.

So, If someone has some good information I would really appreciate it!

Thanks,

JT

[travelin' texans]

I'm curious as well & have seen 140 a few times.
I just make sure that both on the same side are running about the same pressure as the sunny side runs hotter so also higher temps.

[camper94]

Well, I finally got an answer! One that I can live with and seems very reasonable.

For those who read RVTRAVEL.COM, there is a gentleman by the name of Roger Marble from RV Tire Safety who wrote back concerning this issue. Roger is a true Tire Expert, who worked in the Tire Industry for 40 years.

At any rate his response was re-assuring. Here is what he said:

From: Roger M
Sent: Monday, March 12, 2018 8:37 PM
To: Jeff
Subject: Re: Safe Tire Pressure after running for hours on the highway?

The general consensus is +20 to 25%

So, this was a real comfort to hear and that my tires are not heating up too much or have too much pressure that could cause a blow out!

Now on to Morryde this summer and having the Independent Suspension put on the RV. Looking forward to that!

[rob_fla]

I do not run my 17.5 tires on our Redwood at full sidewall rated pressure as I do not have a wheel weight of sidewall capacity of 4650 lbs. as the tire shows at full pressure, our actual wheel weight is around 3600 to 3800 lbs. per tire so I run 105 to 110 psi in our 17.5 tires.
Makes the trailer ride a smoother running at the lower pressure.
Go to Goodyear's website and they show the recommended pressure for the different actual weights / loads on the tires.

Same on our RAM 3500, I do not run the tires at full sidewall rated pressure of 80 psi, if I did I would not have any teeth left.
I run the fronts at 70 psi and the rear dual tires at 65 psi. (truck rides much better)

[piper guy]

Same here. I run our 17.5 Sailun at 110-115. And we're loaded heavy. I'm at right around 3800-3850/ tire.

[AlanN]

We run 110 cold, and the TPMS has never gone above 125 for us, with temps staying within 25 degrees of ambient temperature. Four years full-timing now. Hope this helps.

[spindrift]

Agree with Vaughn and Alan. Your trailer should be weighed. Then using a load inflation table, air tires to verified carrying weight. Any more than that and you're creating a harsher ride and more than likely, unnecessary tire wear.

[mhs4771]

The reason it never gets answered is because there are way too many answers, depending who you talk to.
I asked Gary Wheeler of Mor/ryde one day and he said "Side wall pressure", at a seminar by a TST rep he also said side wall pressure and replace tires at 4 years old.
I just know that if you get carried away with dropping the pressure you start running the risk of rolling the tire off the rim when jack-knifing into that perfect spot.
I know that we're running heavy, so my G114s are at the side wall pressure of 125 psi. They're now 3 years old and 30K miles on them and still look brand new.

[travelin' texans]

Most of us fulltimers that have upgraded to the 17.5s are running close to the GVW of our RWs, or wouldn't have upgraded & by actual weights within 5-10 lbs psi of the sidewall pressure, so just go with sidewall pressure & keep it simple. If you have the IS suspension you won't notice if it rides rough or not. If you still have the 16" Gs I'd definitely stay with the side wall pressures regardless of actual weights.