Wolf Pup Tire Pressure - Confused

erich02 · 10-01-2020, 10:02 AM

Hello All! Sorry for a question that has been discussed in many threads. But I do not have an owners manual, I do not have the factory sticker and I can not find psi chart from the tire manufacturer.

I have a 2019 Wolf Pup 16FQ. Tires are Castle Rock ST. On the side it states Single axle 2040lbs - Max 65psi. I have read many suggesting to run at max, is this correct?

I will be hauling with empty tanks and about 100lbs of misc loaded in the travel travel trailer.

IsleDog · 10-01-2020, 10:25 AM

you will want to run those tires at max PSI. this is a cheap chinese tire. some consider them to be "china bombs"

MtBiker · 10-01-2020, 10:45 AM

Yes run them at 65 lbs. They are likely a "C" rated tire. When you upgrade you should look for a"D" rated tire and run them at 65 lbs.
Carlisle Trail HD is a good option.

jadatis · 10-01-2020, 05:41 PM

If you give your GVWR and GAWR , I will putvut in my made extra safe TT tirepressure calculator, and give a full report. Weighing , best per axle-end is always better, but the recomandation of TT maker is also based on these data.

erich02 · 10-01-2020, 05:49 PM

Thank you so much! My GAWR is 3500lbs I believe, it is a 3500lb Lippert axel. My wolf pup is GVWR: 3944 lb.

eye95 · 10-01-2020, 07:02 PM

Go to the virtual rally and watch the video on tire pressures.

On max psi: His advice is only run at max psi if you don’t know your weights. If you know the weights on your tires, use the industry tables to determine your pressure. This guy weighed our RV by tire position, and we have set all our pressures accordingly.

Seriously, watch the video, then get your RV weighed, at least by axle, but preferably by tire position.

Airdale · 10-01-2020, 10:45 PM

Everyone with any RV trailer tire knowledge is going to tell you to run those LRD tires at full 65 PSI. At 65PSI they are providing a little over 15% in load capacity reserves. The minimum for new trailers like yours is 10%.

There is no provision from USTMA or FMVSS to inflate your tires below the vehicle manufacturer minimum cold inflation pressures found in the vehicle owner's manual and on the trailer labeling.

IvoryHemi · 10-01-2020, 11:21 PM

Quote:

Originally Posted by MtBiker

They are likely a "C" rated tire. When you upgrade you should look for a"D" rated tire and run them at 65 lbs.
Carlisle Trail HD is a good option.

Castle Rock ST’s do come in load range D

babock · 10-02-2020, 12:56 AM

You run what it says on the side of your trailer.

jadatis · 10-02-2020, 02:30 AM

Quote:

Originally Posted by erich02

Thank you so much! My GAWR is 3500lbs I believe, it is a 3500lb Lippert axel. My wolf pup is GVWR: 3944 lb.

Then I putted in my made calculator GVWR of 3944 and maxload 2040 is LI 105 and 65 psi.
Gave 63 psi advice.
BUT because ST is calculated in maxload for 65mph, I also substacted 6 LI steps to give tire a dedlection needed for 99mph. Advice 76 psi.
And this is not allowed for your tires.
In earlyer days they recomanded 10 psi higher so 75 psi for 75mph, so draw your own conclusions.

In Europe , where I live , the Continentall-group gives the 65 psi on sidewall, but often also the maximum allowed cold pressure of 10 psi higher converted to kPa.

Then last ,if minimum 10% on towbar and full gvwr used, 3550 lbs on axle so a litte overloaded on gawr.

jadatis · 10-02-2020, 05:49 AM

My last answer was to quick, so more info here.

The 76 psi is the maximum pressure at wich still no terrible bumping, and gives maximum reserve for things like inacurate reading of pressure, pressure loss in time, to low yudged weight on tires, etc. Can be that you calc with all the reserves, but end up with only yust enaugh to give no overheating of any tire, when driving 65mph.

if you dont dare to go above a cold pressure of 65 psi, dont drive faster then 65mph, not even for a minute, and try to keep towbarweight at fi 15% = 590 lbs.

eye95 · 10-02-2020, 06:32 AM

I watched the second video on tires at the virtual rally last night. That industry engineer offers the same advice: Check the industry load/inflation tables.

He has one slide that shows footprint based on inflation. Overinflation (which is preferable to underinflation) reduces your tire’s footprint, which reduces traction and braking. Overinflation will improve gas mileage.

The industry tables exist for a reason. I (and the two experts at the virtual rally) recommend using them.

Airdale · 10-02-2020, 07:18 AM

Quote:

Originally Posted by eye95

I watched the second video on tires at the virtual rally last night. That industry engineer offers the same advice: Check the industry load/inflation tables.

He has one slide that shows footprint based on inflation. Overinflation (which is preferable to underinflation) reduces your tire’s footprint, which reduces traction and braking. Overinflation will improve gas mileage.

The industry tables exist for a reason. I (and the two experts at the virtual rally) recommend using them.

They are quoting FMCSA regulations which are not applicable to vehicles built under the guidance of FMVSS.

FMVSS requires the vehicle manufacturer to set a recommended cold inflation pressure that is appropriate for that vehicle. Then inform the consumer in the vehicle owner's manual, federal certification label and tire & load placard what that minimum cold inflation pressure is. The only acceptable options for the consumer starts at the recommended cold pressures and ends at the tire sidewall max. If that won't do it the recommendation is to adjust the load or get tires with more load capacity.

RV trailer tires are not built to the same standards built into tires with drive and steering capabilities. They are age-out tires.

eye95 · 10-02-2020, 07:38 AM

No offense, but I am going with the industry engineer. The video starts off with a recitation of his qualifications. Impressive.

Airdale · 10-02-2020, 07:52 AM

Quote:

Originally Posted by eye95

No offense, but I am going with the industry engineer. The video starts off with a recitation of his qualifications. Impressive.

Tire manufacturers have no authority in setting tire pressures for Original Equipment tires. Only the vehicle manufacturer has that authority. That's why I assume you're quoting from some FMCSA source.