TPMS - lock nuts on caps?

I don't want to fool around with extension tubes.

I was able to reach in through the gaps in my hubs to attach the sensor caps without the jam nuts.

you can buy extension tubes for your inner duals that put the cap in a better place for adding air. thoes might be what you are looking for .

Steve

This is the unit:

https://smile.amazon.com/gp/product/B07QNV8T31

You will have to watch their little video to see the nuts (more properly "jam nuts"). It's at the 4:38 mark.

Basically, you thread a small nut onto the valve stem, then screw on the sensor cap, then use a wrench to back off the jam nut until it binds against the bottom of the sensor cap. This locks the nut and sensor to the stem. In order to remove the sensor cap, you must first loosen the jam nut with a wrench.

On my rear dualies, it's impossible to get a wrench (or your hand) through the wheel cutout to work a wrench against the jam nut.

I thought about going to a tire shop and having them unmount the outside wheel and install the sensor on the inside and then put it all back together, but then if I ever need to add air I can't as I can't remove the sensor.

Based on what I'm reading here the jam nut is just anti-theft so today I'm going to install the caps with no jam nuts.

https://en.wikipedia.org/wiki/Jam_nut

maillemaker wrote:
The entire unit with 6 sensors only cost about $120 or so.

Could you tell us the brand and model of the system? I have no clue what you mean by "locknuts." TST systems have a cap that just slips, reducing theft by slipping without the special tool. Maybe you are calling a cap a locknut.

OK the consensus seems to be these are just anti-theft to make them difficult to remove without a tool. I'm going to ditch the lock nuts.

I don't think these things are high-theft. The entire unit with 6 sensors only cost about $120 or so.

The Lock nut is normally an anti-theft device.
The Sensors are usless without the matching receiver..
In theory a low theft item.
Especially on dual tires where they can not even be seen
HOWEVER. that said.. You have different sensors than I had.

I found the locking nuts to be a pain, so I took them off. It makes it so much easier when you are checking/adjusting tire pressure, and I monitor tire pressure frequently, especially before hitting the road after the MH has been stored for awhile.

I use a crowsfoot with an 6" extension to tighten my inner locknuts. Get your inner valve stems changed so they angle thru the hole correctly

They are only anti theft. Leave the locknuts off.

maillemaker wrote:
Is the lock nut really needed? Is this an anti-theft mechanism or is there an actual danger of the cap unscrewing?

I believe it's anti theft, but it was such a pain when airing up I took them all off. I seriously doubt they are a hot item in the pawn shop.