Community Forums

Trentkd5ia · 05-30-2023, 11:05 AM

Just installed a new TST TPMS on our Open Road. Five of the cap sensors went on OK and work great, but can't get the passenger side dually sensor to seat. The sensor goes on, the air comes out, but the sensor will not screw on far enough to stop the air leak. I've tried 5 different sensors on the valve, and all have the same result. Steel extension on the inner tire, and when I removed the valve core I expected the tire air to come out. But, none did. Any ideas on what the problem could be? Thanks!

Ranger Smith · 05-30-2023, 03:37 PM

Yea . . . Get rid of the extensions. I had the same issue . . . Most are junk and cause nothing but problems.

Old Scout · 05-30-2023, 03:45 PM

Agree--many valve extensions don't seem to play well with TPMS systems/caps. Ideal solution is a single piece valve-stem, but they are hard to find with the proper length for a given application.
PS--believe TST offers a different length cap depressor peg for this issue--sold separately of course.

Ray,IN · 05-30-2023, 06:50 PM

I agree with the previous replies. If you must use an extension, screw it onto the sensor just long enough to add air, then remove it and place in your tool box until needed again, which for me is 2X a year since I adhere to the Federal Tire Placard in the vehicle.

SuperGewl · 06-08-2023, 09:18 PM

I agree you may have a bad extension. But you should try it on the other side first. Also, the question is, how centered the extension exits the outer wheel. Does it cause the sensor to hit against the inside of the outer wheel? By swapping the extension with the other side you will verify if it is actually bad or if the threads on the valve steam are bad. I have had to replace a brand-new solid extension that is the reason for buying 2 sets of them.

alank · 06-09-2023, 07:49 PM

Try that extension on another valve stem along with the TPMS to see if it works.
The extension has a small rod that goes down to the valve stem valve. If the rod in the extension is too long, it may not let the TPMS to seat properly. If that's the case, the same thing will happen on another valve stem.

The tire you're having trouble with may have a slightly different valve in the stem that doesn't depress quite as much as the others. That may also keep the TPMS from properly seating.

When you removed the valve (I assume from the extension) no air will come out because the valve will still be closed in the original valve stem below the extension. An extension isn't pressurized until you're either checking pressure or adding air. If you add a TPMS, it will hold all valves open to measure the pressure, so the extension will be pressurized all the time.

Do you know for sure if the air is leaking at the TPMS, or is it at the base of the extension?

Spidergawd · 06-13-2023, 09:16 AM

I agree with others that it's probably related to the extension. Consider replacing your valve stems and extensions with all metal stems, LIKE THIS. They require dismounting the tires, as they install from the inside, but they should solve this problem pretty much permanently.

Trentkd5ia · 06-14-2023, 07:16 AM

Thanks for all the responses and good ideas!
The extensions are rigid and metal, and the sensor works on other tires.
We'll be getting new tires next week anyway, so I'll get some new extensions for the duallies.

Safe travelling!