Installing a TPMS Sensor on an ACME EZE Tow Dolly

[vettenuts]

I wanted to install TPMS sensors on my dolly but was fearful that the high pressure valve stem that came with the dolly would flex, fatigue and break due to the weight on the end of the valve stem coupled with the higher RPM the smaller tires must rotate. Not something I wanted to happen on the highway and the loss if tire pressure would be sudden. I tried making a brace for the valve stem, which seemed to work OK but it wasn't a long term solution since some local towing showed the braces were loosening up.

I first spoke with Innovative Balancing, who make the dynabeads that come with the newer ACME dolly and are used to balance the tires. They recommended adding 1/2 oz of additional beads to compensate for the sensor just be safe. In the following photo you can see that you simply remove the filtered core of the valve stem and slowly add the beads. These are available in kits for motorcycles so I bought 2 oz to do the two tires on my dolly and my spare.



With the tire deflated, you can simply put the tire on a piece of plywood and step on the tire near the valve stem, that will easily break it free from the rim. Once you break the bead, you can hold the tire down and carefully cut out the rubber valve stem. Then I installed a 416 metal valve stem from Blackjack Tire (Link to Metal Valve Stem) and snugged it in place. (This was the second metal valve stem I bought and these fit very nice.) Once the metal valve stem is in place, remove the valve core that comes with the valve stem and install the original filtered core seen in the above photo that came with the dolly (or if it is an older tire, filtered cores are easily obtained at a tire shop). Once installed, re-inflate the tire and mount on the dolly. With the exception of the spare, where I dropped the metal valve stem into the tire, it took less than five minutes per tire to swap out the valve stem in my basement. Here is the final installation.



Haven't road tested yet with the sensor in place but this should provide a long term worry free solution to adding a TPMS sensor to the dolly. Hope someone finds the information useful.

[Nomad Mike]

I like it, and will remember this if I chose to go with a dolly.

[Scarab0088]

Nice job!

Is the red tire valve cap the TPMS sender? Thought the transmitters were bigger

Thanks for sharing

[vettenuts]

No, that's the original cap that comes with the dolly. I don't have the sensor on right now because we are not taking our next trip for a month so I don't run down the battery in the sensor.

[KenNJ]

Nice mod indeed. Keep us posted .

[txflyer]

I took my tires down to the local tire shop to have metal valve stems installed and he told me that the high pressure valve stems that came with the dolly were brass all the way through and did not need to be replaced. He assured me that there would be no problem. I doubt he would recommend that if he wasn't fairly certain. Do you think metal stems are absolutely necessary?

[vettenuts]

I knew the metal goes through but it still will flex and the dolly tire spins much faster than the coach tires. Not worth the risk in my opinion. I also contacted ACME and they weren't comfortable installing the sensors on the high pressure stems.

[txflyer]

Thanks

[40IH]

Does anyone use an Acme tow dolly ? I would like to use my TPMS sensors on the dolly tires but hear I need to install metal stems.


The tires have balance beads in them. Once I have installed the metal stems will I have an issue with the beads blocking and causing false readings?


Finally, can I buy the steams at any auto supply store? Do I need to buy a certain type and can I install the metal steams myself

[Stajones]

I have the Acme EZ Tow (w/10” tires) and have had TPMS sensors on rubber valve stems for apx 5,000 miles. A good portion of those miles were at +65 mph. I have not experienced any detrimental results (that I’m aware of). But, I will say after reading this I’m wondering if I should reevaluate my situation?
Thanks for the post and discussion. I love this forum!!

[40IH]

Has anyone added the metal stems to the new 12 inch tires?

[vettenuts]

Yes, I later updated my tires to the 12” tires and wheels. I installed metal stems, added a bit more beads for balance and ran them many thousands of miles prior to switching to flat towing when I bought a new tow vehicle.