General Sailun Operating 'Pressures' (for TPMS owners)

[Scran]

I've moved from 95 psi Samson tires to the Sailun 637's, which are 110 psi, cold. I've been inflating them to max pressure (110) even though I'm running more than 1,000 lbs 'under' their max load rating. However, I'm trying to get a feel for what 'normal operating pressures' are, or should be - and thought some of you likely have more experience with these tires than I.

We're currently in the Dakota's and on the last few travel days our early morning 'tire time' has been in the low 50's, with mid-day highs in the mid-70's. The tires seem to run around 120 - 125 psi once we've been on the road for a good bit, which seems a little high for a 110 start, at these temperatures - but I'm not sure. Temps are warming up, around the globe it seems, and I'm just wondering what kinds of 'maximum operating pressures' I might encounter when ambient air temps are in the 90's, mid-afternoon - and what is reasonable.

Any of you that keep an eye on your TPMS and might be running the same tires have any input? Any discussion would be helpful, so thanks in advance!

[ChuckS]

Not running same tire but running G rated 14 ply tire..have been for last six years.

Typical inflation cold is 110 psi… I see average tire pressure increase to about 118 to 120 psi with outside temps 60 degrees…

At 90 degrees temps the tire pressure runs around 125ish on all 4 tires

I tow at 62 mph

You picked a great tire … IMO that will perform well and last a long time if properly cared for

[CWtheMan]

According to the specs for your trailer it has 6000# vehicle certified GAWRs and they were equipped with ST235/80R16 LRE tires. Those tires were providing about 18% in load capacity reserves at 80 PSI.

Those 16” LRG tires must be running like solid rubber at 110 PSI. Here’s a load inflation chart. I suggest you air them down to a point where they provide 20%+ in load capacity reserves.

https://fifthwheelst.com/documents/C...T-Modified.pdf

[Scran]

Thanks! I know you've weighed in on many a tire discussion and respect your opinion. Accordingly, a 20% load capacity reserve would put me at about 3,900 lbs - or, according to your chart, a cold tire pressure of about 95lbs.

With all the discussion of 'not' underinflating a tire and causing heat build-up, or undue wear on the outside of the tread - I'm wondering what your take on these possibilities is. I was inflating to 110 (cold) to avoid these possibilities, and also to ensure I didn't have excessive sidewall deflection in turning, etc. If you don't think those issues are worth worrying about, I would certainly entertain the idea of trying to air them down a bit!

Appreciate the reply!

[CWtheMan]

Originally Posted by Scran

Thanks! I know you've weighed in on many a tire discussion and respect your opinion. Accordingly, a 20% load capacity reserve would put me at about 3,900 lbs - or, according to your chart, a cold tire pressure of about 95lbs.

With all the discussion of 'not' underinflating a tire and causing heat build-up, or undue wear on the outside of the tread - I'm wondering what your take on these possibilities is. I was inflating to 110 (cold) to avoid these possibilities, and also to ensure I didn't have excessive sidewall deflection in turning, etc. If you don't think those issues are worth worrying about, I would certainly entertain the idea of trying to air them down a bit!

Appreciate the reply!

Trailer manufacturers are required to install OE tires to the load capacity of the vehicle certified GAWRs shown on the vehicle certification label. It is the consumers responsibility not to exceed maximum GAWR loads. So, 20% of 6000 is 3600# per tire.

In my dissemination of the tire inflation pressure rules, one should NEVER inflate below vehicle manufacturer recommendations. With replacement tires having a higher load range than the OE tires, the minimum is to inflate them to a value that will provide a load capacity the OE tires provided. Most consumers want replacement tires with load capacity reserves. Those reserves are set by exceeding the minimum to a percentage above vehicle manufacturer recommendations. Remember, tire manufacturers DO NOT set vehicle tire inflation pressures, vehicle manufacturers do.

[travelin texans]

My last 5er I replaced the GY 16" G rated tires running @ 110 psi after about 60k miles/5 years with Sailun H rated 17.5" wheels/tires running @ 125 psi & didn't notice any difference in ride or things shaking apart any worse than before. On both tire brands a 20% increase in pressures due to temperature wasn't uncommon.
Running them at max cold inflation would be my recommendation, legal or otherwise, or why upgrade to the next higher load range then deflate back to the originals load rating, seems counter productive.
Also tire manufacturers have allowed for the pressure increase due to temperature. Another reason to inflate to max, the temperature will increase due to under inflation as well as ambient temperature.

[flybouy]

Agree with Travelin Texan. To me it's counter-productive to increase the tire rating then run it at a lower psi. I've never seen a dump truck driver or 18 wheeler deflate tires after the load was removed. What am I missing?

[JRTJH]

There's a difference in "prudent" and "over-kill"...

If you have a trailer with 3000 pound axles, installing tires "1 or 2 load ranges above the OEM tires" likely would be prudent. Installing tires "4 or 5 load ranges above the OEM tires" would be over-kill.

There is such a thing as installing too much tire on too little a trailer.....

Is it possible that installing LRG tires on a "lightweight trailer designed for LRE tires is "more than prudent and enters the realm of over-kill" ?????

As CW mentioned, running LRG tires at 110 PSI on a lightweight trailer is "akin to running on solid rubber tires".... When you have to "air down the tires" 25 or 30 PSI to keep from shaking the trailer apart and still have a 20%+ reserve capacity, IMHO, you're entering the realm of over-kill with way too much tire for the application.....

I have a 3000 pound diesel 4WD tractor with 4 ply industrial tread tires. They are 10 years old and replacements cost $250 each. I "could" (but won't) replace them with 20 ply tires that run at outrageous pressures and are designed to support industrial equipment weighing hundreds of times my tractor's weight. Will they fit the wheels ? Yep. Is it "prudent" to spend $4500 per tire for something I'll NEVER fully use and certainly don't need for daily operation??? NOPE.....

I think (again MHO) that LRG tires are not a "prudent" tire choice for many trailers.... They're excellent for heavy trailers, but over-kill for smaller trailers, many with 5000 or 6000 pound axles.