Replacement Gaskets for TST Flow Through Sensors
Updated 05/22/2025 | Published 05/20/2025 >
Question:
I have 6 TST 507 flow-through tire pressure monitors that came with my Dynamax motorhome I need a replacement kit of the rubber gaskets that seat down in the valve stem. Dont really need the O-rings but will get them if they are part of the gasket kit. Do you have the replacement gaskets? Thanks.
asked by: Stew T
Expert Reply:
Hey Stew, thanks for reaching out!
What you're looking for is the Replacement O-ring Kit for TST SG Flow Through Sensors # TST99FR. I'm not seeing that the gaskets are available on their own, but they do come in the O-Ring kit.
Are the gaskets worn down, or did they fall out or something like that?
Product Page this Question was Asked From
Replacement O-ring Kit for TST SG Flow Through Sensors
- Accessories and Parts
- TPMS Sensor
- Tire Pressure Monitor Parts
- O-Ring
- TST
more information >
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Stew T.
5/22/2025
Thanks for your response, Jon. I have changed the gasket a few times on this sensor but am still experiencing a slow leak. It was on a valve stem extender (an inside-rear tire on the coach) but I removed that, thinking that the leak was from the extender. Still a slow leak. I have been careful about not over-tightening the sensor — only turning it 1/4 turn after cannot hear air hissing anymore. I have sent it back once to TST and it still leaks after I re-installed it. Suggestions please? Thanks very much. Stew T