tire pressure for t@b 400 tires

kaylevine1

I am getting a  tire pressure monitoring system for my t@b 400 and realize I don't know what the recommended psi is? how can I find out-I need to check my tires and have inflated to the proper psi when I set it up I know what it is for my truck 35-38 psi but no idea what is recommended for the trailer tires-Kay-I feel like such a newbie-I got a electronic tire pressure checker but have not used it yet.

Awca12a

Look at the sticker on the drivers side near the front.  It will have your tire specs. 

lkc001

@kaylevine1--the tire pressure is stamped on the side of the tire.  You should go by that stamp.  Unless your unit is new and you have been the only owner, you do not know if those are the original tires and then the sticker may or may not be correct.

falcon1970

Even if new and you are the original owner the sticker might be erroneous--mine is.  Go with the max tire pressure value molded onto the tire.

Awca12a

Have to disagree with the comments here to use the sidewall.   The tire sticker shown below can be found on the drivers side of your trailer.  The specific tire size, specs and cold tire pressure number all went into determining the cargo weight number shown.  In this example, using a 235/75/15 tire at 50 PSI gives me a maximum of 1010 lbs.  If I load at 45, I can expect a drop in the cargo carrying capacity but will get a softer ride with less bounce especially when the trailer is empty.

The tire sidewall, however, is a maximum tire pressure not the "recommended" one and you would vary that figure depending on your load and specific use.  As I'm not an expert, perhaps this post from TireTrack might be of help from an "expert".   Of note is this paragraph although the entire post is of value:
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=8

• "The pounds per square inch (psi) pressure number branded on the tire's sidewall identifies the maximum cold inflation pressure that specific tire is rated to hold. However, the tire's maximum pressure is not necessarily the correct pressure for every vehicle upon which the tire can be used (almost all vehicle manufacturers' recommended tire inflation pressures are less than the tires' maximum pressure)."

] 

ScottG

Does the 400 use trailer (ST) tires or regular automotive tires. I would assume trailer tires but it seems I've heard reports to the contrary.

My limited understanding is that trailer tires are typically intended to be run at their marked pressure (which on my 320 is 50psi).

For regular automotive tires the maximum rating is just that, the maximum pressure the tire is designed to withstand. On my automobiles I like to run a few psi higher than what's indicated on the door sticker, but nowhere near maximum.

Of course if you are running automobile tires on a trailer I have no idea how the inflation rules would apply. trailer tires and passenger or light truck tires have different constructions that allow them to work properly in their intended use.

See, @kaylevine1, there's no such thing as a simple question around here!  :-)

Awca12a

On both my T@B and my Airstream, we run ST tires but especially on the Airstream, I don't follow the sidewall because it would be crazy high.  On the Boondock Light trailers, we have the Rainier per the attached PDF.  If the tire MAX and the sticker match then great but given the variety of tires that might get used over time that fall under a ST rating of the Size Dimensions specified by the manufacturer, you will likely have better results over a range of wheeled equipment if you used the door sticker inflation figures instead of the tire.  YMMV

kaylevine1

after I got home the other day I looked at the tires-they say 50 psi

kaylevine1

so got my digital tire gage in n checked passenger side 41 driver side 39-got out my hydraulic portable jack\tire\lug remover and plugged into 12 v outlet at sink-passenger up to 46-threaded cord under trailer to driver side-it reached!! driver up to 47-i also sprayed n wiped tires with 303 sun protectant as well as wiped my vinyl cover on my truck bed down with the protectant, washed truck and trailer and opened the windows and aired her out for a few hours-still has that factory glue smell when shut up for days-got oil change n tire rotation on truck-have res for a state park about 3 hours away for Easter weekend-I'm ready for the summer
-Kay

DenisP

I posed the question to etrailer: My Tab 400 camper’s original tires are load range C with a max inflation of 50 psi. The trailer rating sticker gives an inflation of 50 psi. I have replaced the tires with Goodyear Endurance tires load range D with a max inflation of 65 psi. What PSI should I inflate the new tires to? 50 or 65psi - or somewhere in between?

asked by: Denis B

Expert Reply:

When inflating trailer tires the recommendation is to inflate the tire to the max tire pressure listed on the sidewall when the tires are cold. So if your max pressure is 65 then that is what you would need to inflate to when cold. The increased pressure when hot is normal.

If you don't inflate to max pressure the tires will not get their full capacity and heat will build up which will cause premature failure.

N7SHG_Ham

@DenisP and that is the same advice I have been given by tire stores too, always run ST tires at the maximum cold inflation pressure on the sidewall.

kaylevine1

the tires do say trailer tires

kaylevine1

and it says-maintain 50 psi-I'm assuming by cold you mean not after having just been driven-not literally cold as it very rarely is "cold" here is south Louisiana-thanks to all for your input!!

ScottG

@kaylevine1, sorry, but you have to drive north of the Mason-Dixon in January in order to properly check your tires.  ;-)

Just kidding. You are absolutely correct; "cold" in this case means not having just been driven on.

That's not to say the air temperature can't affect your "cold" tire pressure. I check all my tires on a regular basis. In order to maintain the proper inflation, I often have to add a little air in the winter, and let a little out in the summer.

Awca12a

@kaylevine1
These guys nailed it in their explanation of COLD TIRE PRESSURE
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=73


This is from the Unofficial Guide definitions section:

·         Cold Tire Pressure:  This appears on the tire sidewall where it states the Maximum PSI.   Most of us understand this to mean at first light when the car hasn’t been driven anywhere as driving heats up the tires and the air inside.  Engineers would more specifically say that the MAX is the inside tire pressure when the ambient temperature is at the index value of 68-deg F and that this changes by 2% for every 10-degree of temperature change.   For the rest of us this means that since the vehicle rests on the tires, and tires are supported by the air inside, when it’s hot out the air expands and when its cool, the air contracts.  If you drive a perfectly inflated vehicle from Florida at 70-degrees average temperature to Canada with a 45-degree average temperature, the tire will need more air when measured cold the following morning because cooler temperatures are contracting the air volume and the air volume is what keeps the tire inflated.  The reverse is true when you go in the opposite direction and you’d need to let some air out when you got to Florida to stay at your MAX rating.   This is why you check tire pressure seasonally.

kaylevine1

Thanks everyone!!

wooper

After buying my T@B a three weeks ago, I'm still going through everything.  Today I checked my tires and they were at 40 psi, I'm assuming that's what the previous owner had filled them at.  I filled to the recommended 50 psi on my tires and hauled it 100 miles today to the opposite side of town and found the trailer very bouncy...much more so than at 40 psi, which makes sense.  The trailer was empty, so I'm wondering if I should lower the psi when empty or keep at max...I figure the tires will last longer when properly inflated, but it felt like I was driving on two balloons.  What do most of you do?

Bayliss

@wooper, on my 320 S Boondock Lite, I keep the air at 50 psi cold, which is working well for me.

Verna

40 lbs works very well on my T@B 400, through about 15,000 miles or so. 

kaylevine1

pretty hot here in the south-I try to keep between45-47PSI I also keep my fresh water tank at least 1\2 full and I have not found to be as bouncy like it was when I first hauled it home from the dealer when it was empty\lighter

jules2go

I recently bought a Ryobi cordless tire inflator and it is a great tool. Anyone else use one of these?

[Deleted User]

In see on the sides of my original factory tires it says "maintain at 50psi cold" so to me that means exactly that and this is not indicative of the max psi as you typically see on the side if car/truck tires.  I'm used to seeing there "max psi" but the T@b 400 tires specifically say to maintain at 50 psi cold.  

I've been using the "air hawk" inflator.  It's one of those "as seen on tv" items but I love it. I've had it for at least 6 years and it still works great and it gets alot of use.  

patandjeff

look https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf