Do TPMS Affect Tire Balance? How About Stem Extensions

[lkncyclist]

When adding TPMS TST 507 Flow Thru's will this affect the balance of the tire and what if you need to add a valve extension to the outside dual?

[wolfe10]

On duals it is a non-issue, as the two sensors are 180 degrees from each other. Suspect weight of extension is minimal, particularly when compared with weight of duals. rear brake drum, etc.

Front-- if you already have your fronts spin balanced on the coach and you are really picky, add a comparable weight 180 degrees from the valve stem/sensor.

[lkncyclist]

Thank you Wolfe.

Will let all know how this works out.

[tireman9]

Depending on the size of your tires i.e. 16" for Class-C like mine or 19.5 or 22.5 as on most Class-A you will probably be within the nominal tolerance when you add the TPM Sensor.

My non flow thru sensors from TireTrakker weigh 0.45 oz so this would be less than a 1/3 oz weigh at the rim flange location where weights are placed.

Flow through sensors are a bit heavier (don't have exact numbers but I think about 0.75 oz).

Here is a blog post on tire balance. The vehicle sensitivity chart is especially informative and shows that simply "balancing" the tire & wheel may not solve a ride problem.

Remember we can "balance" a cinder block but I think you will agree that it would not ride well.

[desertdeals69]

Has anyone balanced tires by putting rv antifreeze inside the tire? How about using bb's or something similar?

[elkhartjim]

I've had great success using this product.

[desertdeals69]

I have Centramatics on and they are not 100%. I think that the tires are more out of balance than the balancers can handle. I tried balancing the wheels on my spin balancer but I am having a problem with the machine.

[rossboyer]

I have used Balance Masters on the front tires/wheels of our current and previous coach. They are rings that mount behind the wheel, and the outer edge of the ring has a tube that contains mercury, I think. As the wheel turns, the fluid moves to the opposite side from the out of balance position. They really have taken the vibration out of the wheels. I have not found the need to have them installed on the rear wheels on either coach.

[tireman9]

Has anyone balanced tires by putting rv antifreeze inside the tire? How about using bb's or something similar?

Not a good idea. I believe RMA has a statement against using it. Moisture in antifreeze can attack the steel in belts and body of tire and of steel wheels.

[tireman9]

If you have a poor ride it may not be an out of balance issue but an Out of Round issue. Don't forget its possible to "balance" a cinder block.

My tires were balanced when new and weights added. No noticeable vibration with the addition on both internal and external TPMS and hose extenders on rear 4 tires with no change in the original weights.

[gbrinck]

LOL, Roger. I like your quip about balancing a cinder block! So true!

[tireman9]

Had a thought. There is a difference between Measurable and Meaningful. In fact I did a blog post just on this topic. But here is a simple test anyone here can do.

Stop at a tire store and ask for a couple of old 3 OZ weights. They should be willing to sell you a couple for a buck or even for free . Next drive to your test road. It needs to be smooth and flat. Then slap both of the weights on one spot of a front rim. You don't need the special hammer just use a piece of Duct-Tape to hold them on a flat portion of the rim. ( be sure the wheel is clean and dry so the tape sticks well.

Be sure to use plenty of tape as we don't want the weights to come off at 50 mph. I just used one piece to help you understnad what I am talking about. I would use more tape if I were doing the test.

Now drive sown your smooth test road.

Do you really feel the difference between no weights and weights? If not you know that being out of balance by 6 OZ is not meaningful.

You could even do the same test with one weight and then with no weights. Ideally the driver would NOT be the person applying weights so the test could be run "blind" and the driver not knowing when one, two or no weights were used.

I have seen some data that would suggest the primary reason for ride disturbance on Large RVs is out of round. This can be tires, wheels, hub, centering of the wheel on the hub and even incomplete seating of the tire on the rim. Sometimes you can "fix" a ride problem by simply removing the wheel and rotating it two bolt holes and re-attaching the tire/wheel assembly to the hub.

Before I got all wound up on being 1/2 oz out of balance I would confirm the tire is round to within 0.060" inch. If not I would get that fixed first.