high/low pressure valve stems

[Donald]

I had tires I got from Tirerack mounted at Walmart. Two of the 4 always seem to have a slow leak. I took them back and they said they replaced valve stems. Still slow leak. In the end I only got 30K miles on the two with a leak and they others may have another 10K left. I went to Sams Club for new tires and was expecting rust on the rim. The guy said no rust but someone had used high pressure valve stems and should have used low. Said they must have run out of low pressure ones. Does this sound reasonable? He said you can use high pressure ones for a 30lb tire, but must use a special seal.

 

[punisher]

New one on me, not saying there aren't different kinds of Schraeder valves. I have used valves out of the same pack in my car tires, tractor tires, and the low side of my central air AC in the house. Come to think of it I have seen Schraeder valves with silicone sealing surfaces (vs nitrile or rubber) for use in R134 AC systems.

 

[Quest]

news to me also. Your quick way to test for valve stem (shrader valve) leak is to get some soapy water and dab some on the valve opening side and see if it bubbles.

If your Camry is alloy rim just like my wifey's, then the likeliness of leak around a corroded rim is high. Walmart here actually applied some black goo along the sealing surface of the alloy rim to promote sealing, and I must say that it works beautifully (no leaks on all 4).

 

[dwendt44]

Semi truck tires are usually inflated to about 100 psi.
Car tires are usually 35 psi. If that makes a difference, it's news to me(but I'm no expert).
I do know from experience that some shrader valves are not at tight as they should be.(small leak)
New tires = new valve stems, IMHO.
AND check the valve stems by snugging them up.

 

[RH+G]

I dont think they will use a more expensive high pressure valve in your low pressure tire. High pressure valves are used on the 2500 and 3500 vehicles etc. They have a metal stem instead of the all rubber ones. They will not leak any faster than a low pressure on a low pressure tire.

 

[alreadygone]

Sams Club guy is "Blowing smoke up your Arse!!"

Guys, stem is complete assembly, CORE is insert that you thread into it to keep air from leaking.

High pressure stems are designed for pressures above 45psi. As found on 3/4 and 1 ton pickups. New versions do have rubber base and brass body is exposed over longer section than low pressure units. Rubber base is much larger, thicker, than on standard stems. Also cost much more.

Low pressure stems are suitable for everything from atv/lawnmower service up to ANY standard load car or light truck application.

while I've never seen or heard of anyone using hi pres stems in standard pressure applications, it'd be a totally harmless, leakfree situation.

bob

 

[alreadygone]

Why wasn't this post started, or moved to tire/rim section?

Bob

 

[mechtech2]

The guy [Sam's Club] reported an anolmaly he saw.
His conclusions were wrong, however.

 

[Donald]

So now I can expect continued slow leaks with these new tires if its not a valve stem issue? The Sam's Club guy said the rims (plain steel ones) had no rust.

 

[Matt_S]

If they did a water bath test to diagnose the leak, which is nearly the universal way to diagnose tire leaks, I can't see how they could've gotten the source of the leak wrong. If the Sams Club guy said it was a stem, you've got a very high chance that was it despite the fact that he's talking out his backside WRT the low-vs-high pressure stems.

Unless the guy's blind, that is.

 

[alreadygone]

Could very well have been a stem issue, just not caused as guy stated. If they do continue to leak and you don't have a local professional who comes well recomended, get a spray bottle with a high soap to water concentration, jack wheels up so they'll turn and find leak yourself.

Bob

 

[Lonnie]

Speaking of tire stores and tire pressure, have you ever experienced getting the tire pressures set correctly or even consistently? For me, never. When I get my car back I always check it when I get home knowing that they are hot, and then checking them again when cold. I have never had them even close. I consider close withing 3-5 psi. I have an accurate gauge with a leak down valve and split the marks when I set the pressure. If it's just a rotation and balance I say don't touch the pressure. On new tires I give them values and they never hit it. On my wife's car I asked for 36psi front and back, a Volvo Wagon and got a low of 22 and a high of 40psi. Makes you wonder about those drivers that never check.

 

[dwendt44]

They may have dropped their gauge a few times so it's off for sure.
I too have an accurate gauge and won't let it out of my sight.(I just can't remember where I left it last

).
Suggest that the tire changer guy get a new gauge, or at least have his checked.

 

[TBJ]

As a person who works in a tire/oil shop, I will never trust another technician to put in the right amount of air in a tire. As for wal-mart, most techs there would not know what supplies cost, they don't have to care about that, it's all about the service to the customer, that's why the tire shop is physically connected to the store, that's where they will make their money.

As for that tech's diagnosis, I think he was partially correct, the outside of the high pressure stem sometimes I think is too stiff compared to the normal ones and with the "right" wheel, your gonna get an air leak where contact is made, not the valve itself.

 

[oldmaninsc]

Quote:

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Speaking of tire stores and tire pressure, have you ever experienced getting the tire pressures set correctly or even consistently? For me, never. When I get my car back I always check it when I get home knowing that they are hot, and then checking them again when cold. I have never had them even close. I consider close withing 3-5 psi. I have an accurate gauge with a leak down valve and split the marks when I set the pressure. If it's just a rotation and balance I say don't touch the pressure. On new tires I give them values and they never hit it. On my wife's car I asked for 36psi front and back, a Volvo Wagon and got a low of 22 and a high of 40psi. Makes you wonder about those drivers that never check.

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I agree 100 percent. I've had the same experience. I recently purchased a set of 4 tires for the wife's Camry (at Sams Club). The door jam sticker calls for 29. Two tires were at 35, 2 were at 22.
The other thing I've noticed is on rental vehicles. I've rental several vehicles this year, and most all of them had way too much air in the tires - not to mention being low on oil and/or coolant. For example I just returned an 07 GMC Envoy. Gm recommends 30 in the front, 35 in the rear. All 4 tires had 42 psi in them. I thought the tire pressure monitor on the DIC was wrong so I got out my trusty digital guage and sure enough it was right on! No wonder the thing rode like a tank!

 

[Gary Allan]

Quote:

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Speaking of tire stores and tire pressure, have you ever experienced getting the tire pressures set correctly or even consistently?

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Well, yes and no. I had 4 new 33x9.50 BFG Mallterrains put on the wife's TJ. The tire service uses a computer generated spec pressure. The tech(s) just punch in the data from the work order and it tells them what to put in. The thing is ...the factory spec pressure is for 30x9.5r15 tires ..and is about 4-6 lbs too low for the 33"'rs.