PressurePro Tire Monitoring, at last

[dtbw]

Some of you may remember my posting some preliminary information regarding a tire monitoring system several months back. Engineering being an inexact science always makes timelines out to be conjecture as was the case on this product. They originally hoped to be in production by early summer, but the development and production tooling stages elongated.

The good news is that all that is behind PressurePro. I received email yesterday that they will be shipping initial production units to a select group for final testing. They skipped end-user beta testing, so these are true production units. The beauty of this new design is that the pressure sensors simply screw on to the valve stem rather than having to remove the tire and mount them inside the rim. The receiver head will monitor 12 tires, so that covers a triple axle trailer, and a dually truck. This company originally developed the technology a few years ago for over the road rigs, but the the pressure sensors were too large and heavy for consumer use. Miniaturization has brought both the size and weight down and has produced a more powerful RF signal at the same time, so this unit does NOT require an external antenna for picking up the trailer tire signals.

I have been told that I will be getting the system around the end of the month, so I will post more info at that time. General ordering availability is stated for about a month later.

The cost is around $500 (for a 6 tire setup such as mine) the unit retails for $475.

david

[Tin Hut]

David,

Do these just replace the valve-stem caps? If so, depending on weight would they add more stress to the stem causing chafe and failure? Also, depending on weight would the tire have to be rebalanced. Love the concept....hope it works.

[dtbw]

Jim,
The pressure sensor caps weight less than 1/2 oz so that should not unbalance the tire. On the matter of flexing the valve stem, I will NEVER allow rubber stems on the A/S again. It certainly appeared to be flexing that caused the stem failure back in Oct. I also think that A/S was partially to blame as they installed long stems with a max PSI rating that was the same pressure as the recommended routine pressure for the Bambi. This gave NO safety factor on the stems. On the replacements, I had steel valve stems rated at 150PSI installed. They are much shorter and of course have NO flex. I have no qualms about putting the 1/2 oz pressure sensors on my current setup.

david

[skip]

It never occurred to me that the tire stems on my streamer could present a problem. It seems so obvious now that you mentioned it, I can't understand why I didn't think of it. This doesn't sound like something I can do myself. What do you suggest? Just using any reputable tire serivce, or does this require some type of specialty tire service? Things like this that we "newbies" just don't think of are what make this forum so valuable. Many thanks.

[dtbw]

This is not a DIY job. The tires have to be removed from the rims to have new metal valve stems installed. Any reputable tire shop can do the work. Metal valve stems are cheap ($2 apiece), but there will likely be a charge for the removal, replacement, rebalancing of the tires. This would also be a great time to check the wheel bearings and brakes on your A/S as the tires will already be off. A few dollars spent on maintenance can save a lot of heartburn on the road.

david

[dtbw]

Well, after several delays, PressurePro has released their remote tire pressure monitoring system. I received my system in late Jan. Overall I give it a B+. It missed the A grade due to the size and color of the pressure sensors. The sensors are a cylinder 1" in diameter and 1" in height that screw directly onto the valve stem. They are black plastic encased and attract too much attention (IMHO). I have recommended that the manufacturer consider switching to grey or silver plastic as that would better blend with aluminum wheels and covers (I am going to paint my with Krylon plastic paint). The weight of each sensor is stated at 2/3 oz. I weighed my six sensors at a total of 4.25oz, so that works out to be just a bit over 2/3 oz each, but close enough. My biggest concern would be mounting these on the end of long rubber valve stems. On short stems or metal stems, they should pose no problems. I did raise the issue with the designer and they indicated that their testing had not indicated a problem, but, you might remember that I had an experience with a valve stem failure on the Bambi due to flexing of the stem alone back in Oct, so that potential is now on my radar. As I replaced all my stems with 150psi metal stems, I have no concerns in my installation. The receiver is well designed and has both audible, visual (which tire) and actual pressure readings. It can be hardwired or plugged into the cigarette lighter. The range of the sensors is stated to be roughly 100' from the receivers so the stated ability to receive remote sensor without an rear mounted antenna should hold up. The sensors can handle upto 150psi. The sensors can also be removed when not towing, but you would need to mark which sensor came off which wheel to avoid having to retrain the receiver after reinstalling them.

The website for PressurePro is www.advantagepressurepro.com

The pricing runs for under $475 for six tires to $675 for 10 tires (the cost increments $50/tire monitored). The receiver comes in several models but the one designed for towed RVs handles upto 16 tires (6 on trailer, 10 on tow vehicle).

While not cheap, knowledge of tire pressure conditions on both the tow vehicle and the trailer could well prevent costly damage due to tire shredding as well as potentially preventing an accident.

At this point, I have minimal experience with the system, but so far it works as advertised. The sensor batteries are rated for several years (they are li-ion), but once they run down, replacement sensors are required. PressurePro has indicated that a reduced replacement cost service will be available for sensors with failed batteries (cost not yet posted).


David

[Porky Pig]

David,

Thanks for the update ... I have been considering this product since your original post.

What are the dimensions of the Monitor ... and where did you mount it?

[dtbw]

Porky Pig,
The monitor is 3"H X 7"L X 1/2" thick. It has two antenna that extend from each upper corner. When fully extended, these two antenna measure 13", which includes the monitor housing. The unit is designed for several mounting possibilities. You can velcro it to just about any convenient location. PressurePro also designed the case to accept sunvisor clips or a windshield suction mount. Neither the visor clips or suction mount are yet available, but PressurePro indicates that they will be selling them shortly. The power cord is small and detaches from the monitor so if you are using a cigarette lighter power cord, you can totally detach yet leave the monitor in the vehicle.

I am leaning toward a sunvisor installation. I think I will hardwire the power cable as I have 12V only inches away from the visor in the overhead console. This will still allow me to unplug the power from the monitor should I desire. PressurePro recommends that you leave it powered up except for extended periods of non use. Since it will be monitoring your tow vehicle wheels this makes sense. BTW, when you disconnect the A/S from the tow vehicle, you simple press a dedicated button on the monitor and it stops monitoring the trailer sensors. This same capability allows you to also stop monitoring the tow vehicle, but that does not make a lot of sense to me.

david

[maznblu]

David, now that you have had the PressurePro system on your rig for a couple of months, how about giving us a report?
Thanks.
Eugenie

[dtbw]

Just a quick update on my continuing use of the PressurePro system. I did run permanent power from the overhead console to the drivers sunvisor. The correct visor clips are not yet available from PressurePro, so I bought a cheapo visor mirror and robbed the clips from it. They are not an exact fit widthwise, but they work and I really like the monitor up on the visor where it is easy to see and operate.

As for the PressurePro itself, I am overall very pleased. I did paint (with PressurePro approval) the sensor units a metalic silver as the wheels on the A/S and truck are both aluminum. The original black finish on the sensors made them far too obvious for my tastes. I just used one of the new spray paints for plastics. I have only had the production unit (I tested two beta versions previously) out for a single trip and one of the sensors is acting up after about an hour at highway speeds (could be either a weak transmitter or a intermittent connection). As it is on the A/S, PressurePro wants me to relocate it to the left front tire on the truck. If it is a weak transmitter, then the problem should vanish. This problem did not show up on the beta units, so I am comfortable that it is an isolated issue.

Having instant, accurate tire pressure readings while rolling down the highway provides a great peace of mind. It is easy to check the tires at anytime and of course should any tire begin to loose pressure, the system will alarm. The system is easy to install and use.

david

[dtbw]

this is per the Goodyear site. Several have questions what is the correct tire pressure. The follow is per tire, so you simply multiply the number by the number of tires and compare it to the GVWR of your A/S. If you run at the minimum pressure that meets your GVWR, you have a softer ride and slightly increased tire wear. Running at max pressure NEVER hurts the tire, but it does make the ride a bit harsher.

I am only posting ST225/75R15 as that is common size that A/S is currently using. You can get the other tire sizes on www.goodyear.com
Tire Inflation Pressure - PSI


ST225/75R15
15 psi=1060
20 psi=1260
25 psi=1430
30 psi=1600
35 psi=1760
40 psi=1880
45 psi=2020
50 psi=2150
55 psi=2270
60 psi=2380
65 psi=2540
david

[nickcrowhurst]

"Running at max pressure NEVER hurts the tire" ?
Am I out of date on this? I've always understood that a correctly inflated tire has the whole of the cross-section of the tread in contact with the road. If inflated below this pressure, the edges of the tread will be in contact more than the centre, and the edges will wear. If inflated beyond the correct pressure, the center of the tire will wear out before the edges. At the correct pressure, the whole of the tread is equally in contact, and is able to do its designed job of adhering to the road surface. Passenger tires are usually kept at one pressure, as the load is reasonably constant, and car drivers don't want to adjust tire pressures just because two passengers have got in the back seat. However, with trucks, the difference between loaded and unloaded weight is highly significant, so the pressures are adjusted according to the load, and the tire pressure charts from the tire manufacturers. An Airstream has a fairly constant load, so my trailer tire pressures are adjusted for the maximum gross weight of the trailer, not the maximum pressure of the tire. Am I out of date on this? Nick.

[dtbw]

Per Goodyear, running tires at max inflation will NOT result in the center bulge you mention. If on the the other hand, you overinflate significantly, say 10psi when cold, then you could cause the problem. Underinflating and improper wheel alignment are the cause of most premature tire wear situations. When I talked to Goodyear on the matter, they flatly stated that running running 5psi below adequate was far worse on the tirelife than running 10psi over max inflation. They did not recommend either as both cause problems, but underinflation was more damaging. Also, over the last 30 years, I have consistently ran all my tires, on all my vehicles at or near max inflation and never had any unusual wear patterns. I have also gotten consistent long tirelife (40K or more), even on my vette tires which are notorious for short tread life.

As for checking pressures, they should always be checked when the tire is cold. It only takes a few miles of rotation to heat the tire and give a false elevated pressure reading. I have active monitoring on both the vette and my tow vehicle & A/S so I can watch the pressures as the tire heats. I have found that the A/S tires at highway speeds reach 72psi with a cold inflation of 65. My LT truck tires, which run at 50psi cold, increase to about 56-57psi. BTW, I could run 55psi on the Bambi as it has a GVWR of 4550, but Goodyear recommended running at max as the tires run cooler and the ride harshness increase in pretty minor on these tires.

Tire pressure is something of a personal decision, but I have asked Goodyear, Dunlop, Michelin, Pirelli and all have stated that running at max pressure will not hurt the tire and will typically increase its treadlife.

david

[nickcrowhurst]

David, thank you. I confess to now being confused as to why the tire manufacturers produce the load/pressure charts for LT tires if max. tire pressure is always good. I'll just have to get used to being confused! Nick.

[dtbw]

The charts are produced to show the minimum pressure for varying loads. You also get a softer, quieter ride at the lower pressures, but the lower pressure can lead to other issues such as the infamous Firestone/Ford fiasco. Lower pressures allow the sidewalls to flex more and that also leads to a bit more heating and wear, but the tires should last the typical mileage as long as never underinflated. Running at max inflation results in longer treadlife, slightly better gas mileage at the expense of some comfort.

david