Tire Pressure Monitor Recommendations

[No Name]

I've been using the TireMinder I10 system now for over a month and about 5k miles. So far it's been a really good system for me. I bought the 145psi I10 sensors/kit with 10 sensors and then added 2 additional pass-through sensors that I used for the inside drive tires. The drive axle tires require adapters depending on your valve stem set-up. For me I had to install the TireMinder "J" adapters on the outside drive tires and used the normal sensors that came in the kit. On the inside drive tires I had to use a 4" Tire Minder extension then put the pass through sensors on. These both keep the sensors from contacting the rims. On the Jeep I just used the regular sensors that came in the kit. For the first couple thousand miles I was pretty paranoid and kept checking the extensions/J-adapter on the drive tires and found that once you get them, IMO, uncomfortably tight onto the valve stem, they stay put (the sensors are NOT supposed to touch the rim – I guess it physically beats them up and probably throws off the temp reading). (the secret to installing the inside tire 4" adapted installation is to use a pass-through socket set with 8" of extensions on it and a 7/16" socket - a 7/16" stubby wrench does the job on the J-adapters). I had a spot on the dash that had something velcro'd to it at some point that fit the display space perfectly. The hub is mounted in the engine bay above the batteries and I have not had any connection issues so far, still using the alligator clip set up it came with – it hasn’t been shut off since I installed it in a Walmart parking lot over a month ago. I’ll clean the install up soon.

Running around in TX pressure and temp are huge concerns. Using this system I was able to find the correct pressures that yielded the weight capacity I needed, pressure at continued hwy speeds (75-80mph) and cool temps to keep the tire from separating. My wife was rather frustrated as we were stopping every 70 miles or so for me to constantly adjust pressures and I found that - on Michelin 315's all the way around - that I run 110 cold resting in the front and 100 in all rears. The Jeep I run 38 except for the driver front I run 37 (I had it aligned but think there's something a tad off causing some additional friction on that corner). So in reality after using for several weeks the cold tire pressures are actually now 110 steer and 100 drive/tag at 70deg resting from the night. This is actually great as once it hits 105deg ambient, 4pm at 80mph the steers will come up to 128-129, drives will hit 117-120 and tags will be 119-121. Considering I have a 16,500 steer, 20,400 drive and 12,000 tag axles and a fully laden weigh slip (all tanks full, including grey and black & fuel and all people/dogs inside) showing 15,000, 19,500 & 11,700 respectively putting be ~2700 under 48,900 GVW (FYI - Jeep adds 4600 full of fuel to gross putting GCVW at 50,800). The 315's handle the load within their operating range. The tags always run a few degrees hotter and a couple PSI higher - it's probably a combo not being in the cool airstream and that 3000+ pound Cat hanging off the back. Also notice the inside drives run a couple degrees hotter as well, my guess is that’s the steel wheels not dissipating heat like the aluminum outers. Tires when they're hot are around 120 degrees, normally at or just under 110deg - never seen them over 130deg, including the Jeep (when figuring out pressures in the beginning I did see 133psi and 137deg on one of the fronts – highest I’ve seen, but never since). Always heard that 200deg is the point where tire failure from heat can occur, by 250deg you’re going to have a heat related failure. Read numbers anywhere from as low as 180, 185, 190, 195 – 195deg seems to be the consensus for truck tires where they start to break down from heat over time. So I feel a-ok running these pressures to achieve the required load and the temps tell me I’m ok running at those sustained hwy speeds. The BFG’s on the Jeep will get up to 41psi (factory tire pressure) and sometimes 42-44, but max inflation is 50psi so no worries there. Verified the TireMinder temp is accurate to my Klein IR heat gun and pressures are accurate to most pressure gauges.

I looked at the RVI brake system – super fancy and I like the use it as a level feature and the iPad is fancy. I tend to gravitate towards simple dedicated, easy to troubleshoot systems vs the connected/integrated/all in one/on the net/control from anywhere phone/iPad type of devices. The TM !10 is a simple display that cycles between the coach and toad. You have to press the top button momentarily to toggle between pressure and temp – on this coach, the PSI and temp readings are really close so sometimes I have to double take to verify which mode it’s in. The display does auto-off when it’s not plugged into the charging cord, otherwise you have to hold the top center button for 4-5 seconds. The battery lasts for days. Charging cord is a USB-C so it doubles as my phone and iPad charger we use for TruckerPath (awesome app, fuel discounts, etc., best part is it gives you the truck routs where the nav on you phone will route you down residential streets where you bus starts trimming trees and with a toad attached, may be too tight to navigate).

Twice in the last 2 weeks I’ve had it display a red box around one tire and alarm slow leak. I monitor and there is no such thing. A quick power cycle and back to normal. This is probably a battery in the sensor getting weak. They are easy to change as the TM cap simply unscrews and battery slides in. The Kit came with 2 batteries/sensor, but no telling how long those have been on the shelf. I also believe TM will send you free batteries for life – just keep you original receipt. RVI Brake you have to send back to them if I recall (tying you to RVI which was a con for me – the other is getting an additional sensor, Camping World sells both systems but seems to have a great selection of TM sensors (2-packs), valve stem adapters/extensions, etc.. All in from Camping World I was under $600 (I10 10-pk, 2pk pass through sensors, 2pk 4” straight valve stem extensions, 2pk J valve stem adapter, tax). I think RVI is at least 50% more mainly due to the iPad – but it does double duty for the brake controller.

I may be singing a different tune in another 5-10k miles, but so far so good – the TM I10 is doing everything I bought it to do just great and reliably. No matter what anyone selects, having TPMS w/temp is a must have item IMO. Forget the cost and hassle of having a tire failure and waiting on the roadside, etc.. With a system like this you can tune you pressures and speeds to minimize non-road hazard related tire failures.

Here's some photos - mind the brake dust - we are mobile once again.

[No Name]

So we had a slow leak occur, about 2 psi every 15 driving, 1 psi per 15 min sitting. Wound up being the TM 4” extension - o-ring pretty chewed up - lasted over a month and over 6k miles…. (Inside drive tire). Other side is just fine. Had the outside drive tire start leaking a couple days later, same side. Wound up being the “J” extension had loosened slightly, tightened up and fine since. I think it might have something to do with the rotation and thread direction on the right side - that’s the only side the extensions loosen on.

[No Name]

After 20k miles I will confidently say the pass-thru sensors are not good for bus tires. I first had problems with the 4" extensions and then the sensors themselves, to the point I do not run any extensions or sensors on the inside drive tires. The pass/flo through sensors pass such a low volume of air that adding air through the sensor from a 120-125psi source to a 100psi tire is at a speedy rate of about <1psi per minute - without a sensor I go from 100-105psi in about 30-45 seconds for comparison. The normal screw-on cap style sensors have been 100% reliable and bulletproof. I have had to replace 2 batteries (different sensors) but they seem rock solid thus far. I did have a tag tire blowout, then 324 mi later, my brand new 14 year old Double Coin brand 315 tire blew... My drive and tags were all right at 10yr old and only had another 10k miles left on them (about double the tread wear indicators) so we just bought 6 new tires. We had the tire folks put the valve stems facing outwards on the outside drive tires to use the cap style sensors without any "J" adapters or otherwise. You can tell if the inside tire is losing pressure because the pressure will increase on the outside tire as the load increases.

I read some other posts on different positions regarding carrying a spare tire and based on my post covid experiences I can attest that finding someone to change you tire is pretty easy. Finding someone who has a Michelin 315/80R 22.5 X-Line Energy Z Coach tire in stock within a 500 mile radius is same odds as getting 4 out of 6 numbers on a lottery ticket. I found a tire (correct Michelin) almost 100 miles away - luckily the 2nd blowout was less than 4 miles from an RV park right off the highway, with 50A service. So I found a tire shop (Pomps) under 100 miles away that had 2, correct, tires in stock as well as a mobile tire crew. I ordered the 6 tires, 4 day wait for them to arrive. I also had to take my spare to them to have them mount one of the 2 they had in stock, that were already 2 years old by date code. The following day their mobile service brought the tire out to mount on the blown out tag and took the blown spare wheel back to their shop. The following day when the remaining tires arrived, I drove to their shop and replaces the remining tires. Blow out Sunday night, Back on the road Thursday evening.

What did I learn?
1 - Double Coin tires are the cheapest of cheap with the 1st blowout Speedco mechanic stating "they're better than a recap" and the Pomps shop saying they sold recaps but not Double Coin... My double coin was brand new with stickers still on the tire...
2 - Finding a mechanic to change your tire is pretty quick/easy, even on a bus (my AAA Premier RV even pays for it).
3 - Finding a 315 (or larger 365) Michelin coach tire, good luck. Having a quality spare (like a Michelin) is must have in my book as it will allow you to find a tire shop that can/will order your tires and you can continue your trip while they are in transit to the tire shop.
4 - the mud flap frames between the drive/tag axles act as a "tire grabber" as the 1st mechanic called them and actually grab the tire, stop it from spinning around and beating up your coach. I do have a pretty good dent in my muffler though, no leaks. My tire grabber looks like an elephant stepped on the "rungs" but it's still there, mud flap is gone, and it worked twice, very well, allowing me to drive almost 4 miles (at walking speed) to the RV park after my spare blew dragging a 7ft alligator but the tire was not turning (wheel was spinning inside the tire). I have 2 options, Prevost for $370/ea available mid November, or a hammer and blocks of wood (or a metal shop to do the same).

So did the tire monitors give indication before the tires blew (pressure/temperature) - no, only alarm upon/after the sudden loss of tire pressure. Never high temp, rising pressure, etc... What is the benefit of TPMS - prevention & notification of situations that could cause a blowout. Rising tire pressures, rising heat, dropping pressure/leaking tire, etc.. At time of both blowouts the tires were at 118-121 psi and 125 degrees +/-, consistent on both for the previous 100+ miles prior to blowout. The Michelin XZA threw the tread and removed my mud flaps and dented mu muffler - the Double Coin split in half and just dragged.

I have a pretty good XZA-2 spare now. The new X-Line Energy Coach tires are much quieter and seem to track better on the steer axle - IMO. Current price $1025/ea (MSRP $1300/ea). 6 tires, mounted, spin balanced including the trip/callout to swap at the RV park - $8000 on the nose for 6 tires. A little inflation from the $400-700 pre-covid prices posted on this site.