[Kip-on-truckin]

This week I got my first flat in the PM. Looks like a chunk of steel went through the tire. Luckily, by the time it was flat enough to notice I was at a truck stop with plenty of space to change it. The TPMS light came on immediately though.

Because I've never done this on the PM I had to bust out the manual. In short, this is either the greatest spare tire system in the world, or the worst. I really can't tell.

You use the jack handle (2 piece) and a weird adapter to operate the rear winch mechanism. You crank it and the tire lowers on a cable down to the road, then you wind out about 5 feet more of cable and get the tire upright behind the van. Then a wing nut releases the tire from the winch, and you crank the cable back in. I'm not sure how well this is going to work when I replace the spare under the van, or how well it will hold up after 10 years and lots of grime.

The scizzor jack is pretty self explanatory, as are the jacking points. But the wheel has two spikelike studs that come out of the hub, which are offset so they locate and pilot the wheel as you install it. It doesn't work well, so it was a lot of back breaking to lift the wheel up and wiggle it onto the hub. More to the point, ONLY rims with the locating holes will work on the PM, though I assume you can remove the piloting studs. They appear to bolt into brake rotor "hat".

The jack handle itself is also new to me. It's a two piece that slides together to make a T shape. You can get extra torque by sliding it more to make the T into an L, and when the handle hits the ground you can slide it to the other side and start cranking again. Not sure if I like it or not, but it's different.

All of these tools can be found in the black plastic suitcase that's under the passenger seat. But the jacking instructions are in the manual.

Since it's clean and easy, you all might want to open the suitcase and get familiar with how the system works. Better that than find out on the side of the road, in a snowstorm.

 

[Kip-on-truckin]

One last thing: the TPMS system needs 1/2 mile or so to "learn" the new tire. But because the front pressure is 60 and the rear is 72, odds are 50% that you'll have the wrong amount of pressure in the spare. The TPMS seems like it's very sensitive, which makes sense because it's there to tell you if your tires are low, not flat. I'm assuming that when I correct the tire pressure in the spare, the TPMS light will go off.

 

[Kip-on-truckin]

Another note: As far as I can tell, the TPMS does NOT read the tire pressure in the spare as it's mounted under the van. Some Toyotas include the spare, but most vehicles only rear the 4 corners.

 

[Storming]

TPMS light won't go off until you repair/inflat pressure on flat tire. Has nothing to do if its on the vehicles drive system or not (the flat tire is sending signal to the vehicle even sitting in the back of your van)

 

[keeponvaning]

Sounds like fun! I'm going to remove the centering thingys when I mount my sprinter rims as they won't go on with them there. Of course the sprinter rims and tires don't have the tire pressure thingys either so I guess I will just leave the light on for it, or I may just wait till I wear out the promaster tires and then just switch the tires not the rims! Nothing is ever easy is it!

 

[Dwight]

Thanks for the tips. I think I need to print the manual pages and put them in the box under the seat. I don't keep my manual in the van.

 

[jimmbomb]

yes.. thanks for the excellent write up and descriptions on the workings..
keep up the good job on keeping us informed.
thanks again

 

[keeponvaning]

Can anyone enlighten us as to the location of these sensors? Are they part of the valve stem? Do we need new special valve stems every time we change tires or rims? Are they reusable? Are they located inside the tire? Inquiring minds want to know.

 

[proeddie]

... But the wheel has two spikelike studs that come out of the hub, which are offset so they locate and pilot the wheel as you install it. It doesn't work well, so it was a lot of back breaking to lift the wheel up and wiggle it onto the hub. More to the point, ONLY rims with the locating holes will work on the PM, though I assume you can remove the piloting studs. They appear to bolt into brake rotor "hat".

K-O-T,

I discovered the locating pins when I changed my hubcaps. I didn't like the small covers so I ordered the full hubcaps to replace them. They look much better on my graphite PM, at least to me. I learned the following:

The locator pins are OK but I found that (after the first wheel) I only jacked the tire so it was just skimming the ground. By doing that, the weight was on the ground and it was much easier to tilt the tire into place and use the locator pins to line it all up.

The hubcaps are held on place by the wheel studs. One of the hubcap holes is elongated, so you put the tire on loosely with a single stud, then slide the hole with the elongated hole over the stud and push the hubcap into place. Then continue to add the other wheel studs to the other 4 holes. I got pretty good at it after the 4th one!

I used a floor jack, so I guess I should take out the factory jack and try it. Probably should try lowering the spare too!

Ed

 

[proeddie]

Can anyone enlighten us as to the location of these sensors? Are they part of the valve stem? Do we need new special valve stems every time we change tires or rims? Are they reusable? Are they located inside the tire? Inquiring minds want to know.

KOV,

The TPMS sensor/sender is part of the valve stem.

Part # 05154876AA
MSRP $78.60Price may vary by dealer

At that price for ONE, better make sure your mechanic knows it's there when they demount and remount tires. It's like this on many cars. They have to be careful with the demounter when they "break the bead" on the rim. They are reusable when you put on new tires (at least on my other cars that have them!).

Ed

 

[keeponvaning]

Thanks, that's very good to know! And the spare doesn't have one?

Other than the light staying on without them is there any reason not to use them (other than the obvious)?

It looks as if Rock Auto has them for about $43 each
http://www.rockauto.com/catalog/x,carcode,3300381,parttype,12036

 

[makevx73]

The story on TPMS for inquiring minds:

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=44

http://en.m.wikipedia.org/wiki/Tire-pressure_monitoring_system

PM's have the direct system.

I had snow tires mounted on my OEM rims this week. With only 4000 miles on them the TPMS sensors are as good as new so there wasn't any need to "rebuild" them. Sometimes they have to replace the little nut that holds them in, as they corrode. Sometimes they have to replace the battery in them, if they can be replaced. Sometimes they just have to replace it. With some vehicles they have to use a device to force the system to "relearn" after rebuilding the sensor or replacing them. Firestone didn't even have info on or could look up on their system how to reset the TMPS after reinstalling my wheels. The tech guessed that, like many Dodges, that them would reset after a few miles of driving. They did reset on their own. I plan on getting another set of rims this winter for my Vancos. Hopefully swapping wheels will be easy and the TMPS will quickly reset...

 

[Kip-on-truckin]

Even $78 isn't too bad. My only experience with TPMS was on a 2009 Ford. Ford is unique in that they use a band around the inside of the rim, to which the sensor is mounted. A flat tire or blowout can damage the sensor, and they are $250+ per wheel to replace, AND you have to have the factory scan tool to get the computer to talk to the sensors. As you might expect, on the Ford I just learned to ignore the dash light.

My flat tire has been patched and is awaiting pickup. Maybe I'll document the remounting of the spare for the forum.

 

[ericsram]

One last thing: the TPMS system needs 1/2 mile or so to "learn" the new tire. But because the front pressure is 60 and the rear is 72, odds are 50% that you'll have the wrong amount of pressure in the spare. The TPMS seems like it's very sensitive, which makes sense because it's there to tell you if your tires are low, not flat. I'm assuming that when I correct the tire pressure in the spare, the TPMS light will go off.

If the front and rear sensors are at different pressures what happens when you rotate tires front to back? are they reprogrammable? Do you have to remove tire from rim to replace sensor?

 

[keeponvaning]

As far as I'm concerned it's just another PITA thing to go wrong and I'd be just as happy to forget about it.

My wife has a Hyundai that has a tip system and the light comes on all the time and when I check the tires they are all fine. I never drive it so I've never bothered to look into it. Just another needles bother and expense I can do without!

 

[makevx73]

As far as I'm concerned it's just another PITA thing to go wrong and I'd be just as happy to forget about it.

Agreed. But in some states your vehicle won't pass inspection if the TPMS isn't functioning properly.

 

[Kip-on-truckin]

The sensors/computer are pretty smart. The spare I put on was at 60psi, and the spec on the rear is 72. Within 30 seconds the computer had recognized the spare and knew the spec for it's position. The light stayed on till a few hours later when I put 75psi in that tire and then the light went off.

This tells me that the computer knows the actual tire pressure of each tire. And since it knows, hopefully when I use a scan tool or iPhone I should be able to know as well. Knowing actual tire pressures is a HUGE deal for heading off potential disaster, and keep mpg up.

 

[Dwight]

How do you use iPhone?

 

[Kip-on-truckin]

Ive never done it, but i looked into it and it should work. A $10 bluetooth dongle attaches to the obd port, and that communicates with a $5 app on the phone. Very detailed gauges, data logging, code lookup, and so forth. Type "torque" into the app store seach to see whats available.

I currently use an old iphone in the pm just for music and podcasts. But if there are good gauges to be had, if consider buying an ipad and setting up as an suxillary dashboard.

 

[keeponvaning]

I have the very system you're talking about on both my iPhone and iPad and I can tell you it isn't very simple to use much less set up. It's cheap, yes, but basically a waste of money in my opinion. It's extremely difficult to get any real data to put into it so you can get anything worth looking at back out. The documentation is absolutely horrible!

If you want to see bigger gauges and spend hours trying to figure out how to set them up, it's wonderfull, otherwise I keep my ScanGaugeII in my OBD port it's much more user friendly.