TPMS/Duals

[garyre]

I have read a few threads on the Cats Eye & Dually Crossfire systems for the rear duals equalizing the tire pressure. I really like the idea of retaining equal tire pressure.

A few questions for the experts:

Looks to me you have to order a specific tire pressure for the Crossfires.. Do you use a lower pressure system than the pressure you are running? ie if proper tire pressure is 90psi, do you need a system <90psi to shut off if one tire loses normal pressure?

Not sure if the Cats Eye is a variable pressure system determined by the user..

Also if using a TPMS will you lose the independence of each tire? ie combining each side into one?

Would like to have the equalization but also the temp of each tire since the pressure should be the same.

Any experience recommendations is much appreciated.

Thanks.

[vsheetz]

With Crossfire's there is one fill point for the two tires, hence one TPMS sensor for the pair. You won't get individual tire temoerature.

[Kiawah]

You currently have some redundancy in a dually, because if you have one tire go flat or blow out you'd get an alarm, and then could slow down the coach while still riding on one tire.

You tie the air together, now a flat or blowout causes both tires to deflate. Not a wise idea in my book.

[bobmac]

Kiawah
No one would buy them if they acted as you believe. In a blowout, the unit isolates the good tire immediately. In a slow leak, it isolates the good tire after a 10 psi difference. I purchased mine to get rid of leaky tpms sensors. I circle check every 2-3 hours and the unit provides a visual indication of pressure which satisfies my requirement. I have had mine for 6+ years without any issues. The manufacturer claims they extend tire life with equal wear but that is a doubtful benefit in an RV compared to a truck.

[dmurdock]

Originally Posted by vsheetz

With Crossfire's there is one fill point for the two tires, hence one TPMS sensor for the pair. You won't get individual tire temoerature.

They make tpms capable crossfires. Also to the OP, the pressure setting is just what the guage will be set for (visible on the crossfire)..you can run any pressure you want. Check out this video of mine..I talk about some of your issues:

https://www.youtube.com/watch?v=bGPTnBIelaE

[garyre]

Some of the reviews on the flow through tpms are not very good. What kind of tpms are you using with the crossfire set-up?
thanks..

[dmurdock]

In the video those are TST brand and are not flow through. The Crossfires setup for tpms have 3 shraeder valve stems..
one in middle for adding air and one on each side for tpms.

[dmurdock]

Here's a pic of the "tpms hose" for the crossfire (you order with these hoses on each side of the crossfire "guage" giving you a tpms port for each tire).

I ordered mine from truckpartsworld.net...I just emailed them and told them what I wanted (psi setting/tpms hoses/22.5 rim so they knew how long the hoses needed to be) and they built the crossfires to my specs and shipped them out.

http://www.truckpartsworld.net/wp-co...1/IMG_0172.jpg

[garyre]

What tire pressure setting on the Crossfires would be recommended? Currently running 90psi but may change as I experiment with load/pressure settings..

[bobmac]

You want the pressure setting on the Crossfires to reflect the load you will be carrying with a provision for one side being slightly heavier than the other if you just had the axles weighed. You can use the tire manufacturer's recommendations for the tire you have and the weight you will be carrying. You will have to change the entire unit if you elect a different pressure in the future. Bottom line is you should hold off a purchase until you sort out your tire pressure.
Unless you have a tag, there is only one correct pressure for your make and model of tire and that is determined by the weight to be carried. It isn't a science experiment.
The Crossfire will display your actual pressure for a +/- 5 lb range from it's rating so there is no point purchasing a unit different from the pressure you intend to use. You cannot readjust the Crossfire yourself. I purchased mine to replace a leaky TPMS system and have found that the visible monitoring provided by the unit continually alerts me to the actual pressure as temperatures change. Good luck, I am certain you will find them to be a great addition.

[Tireman9]

Originally Posted by Kiawah

You currently have some redundancy in a dually, because if you have one tire go flat or blow out you'd get an alarm, and then could slow down the coach while still riding on one tire.

You tie the air together, now a flat or blowout causes both tires to deflate. Not a wise idea in my book.

If one tire is a set of duals goes flat and you continue to drive you will damage the tire with air as that tire is now overloaded by 100%. Unless you slow to less than 10 mph.

[Tireman9]

Originally Posted by garyre

I have read a few threads on the Cats Eye & Dually Crossfire systems for the rear duals equalizing the tire pressure. I really like the idea of retaining equal tire pressure.

A few questions for the experts:

Looks to me you have to order a specific tire pressure for the Crossfires.. Do you use a lower pressure system than the pressure you are running? ie if proper tire pressure is 90psi, do you need a system <90psi to shut off if one tire loses normal pressure?

Not sure if the Cats Eye is a variable pressure system determined by the user..

Also if using a TPMS will you lose the independence of each tire? ie combining each side into one?

Would like to have the equalization but also the temp of each tire since the pressure should be the same.

Any experience recommendations is much appreciated.

Thanks.

I see no meaningful advantage to connecting both tires air chambers together, assuming you set the tires to the same pressure to start with.

If you get a leak in one tire it will bleed off air from the good tire. The load will transfer from the leaking to the good tire which is now running lower pressure than before the transfer. So you will be increasing load while decreasing inflation. Exactly how is this a good thing to do?

Running two TPMS is a good plan. Just be sure your warning levels are set to avoid tire damage.

[Tireman9]

Originally Posted by bobmac

Kiawah
No one would buy them if they acted as you believe. In a blowout, the unit isolates the good tire immediately. In a slow leak, it isolates the good tire after a 10 psi difference. I purchased mine to get rid of leaky tpms sensors. I circle check every 2-3 hours and the unit provides a visual indication of pressure which satisfies my requirement. I have had mine for 6+ years without any issues. The manufacturer claims they extend tire life with equal wear but that is a doubtful benefit in an RV compared to a truck.

IMO correcting the leak with the TPMS would have been a better plan. You can easily destroy a tire in 10 to 30 min of running significantly low. I think all you will do if you discover a flat tire is know you have destroyed two tires. The one with the leak and the one you overloaded.

[Tireman9]

Originally Posted by dmurdock

In the video those are TST brand and are not flow through. The Crossfires setup for tpms have 3 shraeder valve stems..
one in middle for adding air and one on each side for tpms.

Every connection point increases the possibility of having a leak. More connections is not a good plan.