I busted a TPMS valve stem off my '08 Grand Caravan trying to get the friggin metal cap off to add air. The stem was incredibly brittle. Looking back, I should have used a dremel bit to cut the cap off instead of twisting it with gas pliers. The cap was factory Chrysler original design made of nickel plated brass. Most TPMS sensor caps these days are plastic, so I'm switching. A tire shop replaced my tires two months ago and this is the first time I needed to add air. I can't attribute this trouble to the shop over tightening the caps; front brake dust may have contributed to stem thread corrosion. The tire store also told me months ago that one of my cores was corroded in the stem and could not be removed. They drilled a hole in the sidewall of the old tire to remove it. This is the customary workaround these days.


Anyway, I decided to tackle this repair myself after contacting a dealer and tire stores for pricing (repair is $75 to $150 per tire). My tire dealer removed my tire for $8 so I could examine my sensor to find a fix.


Here's what I learned so far:


Most 2008 thru 2009 GC's use a TPMS sourced from Siemens for Chrysler. Mine is labeled as Daimler-Chrysler, part#56053031AD, 433MHZ, FCC Model designation 5WY7900. If you care to see what they look like, just earch ebay with the long Chrysler part#. Dozens of used one's will come up costing around $25 each or $70 for four.


I thought about buying a used sensor but the batteries have limited life and mine are already 6 yrs old. Plus I'm not clear if a reset with expensive TPMS programming tool would be needed when installing a used factory sensor, so I decided against this option.


If the electronics still work OK, you can actually replace a defective stem assembly. A tiny screw holds a metal conductor to the stem base. This allows the stem to work like a mini antenna. Unfortunately, this particular sensor design is not well-supported by the aftermarket as far as selling stem replacement kits. The only supplier seems to be a Chinese source and there are only a few sellers for the stem rebuild kits. The going price for one of these stem kits is around $18. I'm not confident that these rare stem kits are worth their while.


The aftermarket exact-fit sensors are becoming very cheap. For this application, the Dorman model 974-061 is total plug-and-play, no programming tool needed. The cost of this sensor is running around $25 plus shipping. This is a user-friendly install. You just swap out the sensor and drive the car. The grand caravan will re-learn and adapt to the sensor, so to be clear, NO programming tool is needed period. The Dorman design is unique and the Dorman-only stems are replaceable and cost around $8 with washers, seals and core. Dozens of folks have commented that this $25 Dorman TPMS part works perfect for an '08-'09 Grand Caravan.


I decided to buy the Dorman direct-fit sensor and avoid the universal fit units. The universal sensors (that most independent shops prefer) require a $200+ programming tool. I have no interest in going that route. I see that as a never-ending cycle of stupidity for the consumer because they hold you hostage and you must fork out $70 and up for each TPMS.


Frequent preventive maintenance of your TPMS sensors would help minimize troubles in the first place. I would suggest the following:


1) buy a valve stem service tool from a bicycle shop. These $5 tools allow you to chase the inner and outer threads of the stem to clean off any corrosion. They also have an integral core removal tool built-in. Jack the tire off the ground and remove the core to chase the inner threads with the tool. Install a new core and stem kit every year or so. These rebuild kits cost about $3 each and they are sold at places like rockauto, Autozone and AdvanceAuto.


2) run plastic valve caps with integral o-ring. A stem service kit for $3 (less stem) will include new air seal for the stem, new stem nut and washer, new cap and new nickel plated valve core. Do not use a conventional brass core or it will corrode and stick within weeks.

 

I have a tire service light on the dash, How much do you think the dealer will charge to scan for the faulty sensors, Or should I just buy the sensor set? can the sensor swap be done at home if I have a way to inflate the tire or a tire shop is required?

 

When I replace the sensors in my '09 I will be using Schrader part number 28434. They have rubber covered stems and are direct fit, and they do not require programming. The stems also replaceable.



George

 

You have almost no choice. A malfunctioning system will require professional troubleshooting with a scanner tool and the dealership is the most reliable place to get that diagnosis work performed. I think it would be incredibly risky pot luck proposition to change all 4 sensors for close to $200 in sensor parts and labor (tire dismount, remount and balance) while praying that the light goes out when you're done. If it doesn't go out you may wind up paying the dealership hundreds for troubleshooting and rework.


If an alarm light comes up immediately after a tire replacement job, you MUST return to the shop and insist that they fix what they broke. It is incredibly easy to damage a sensor with the tire machine. Otherwise you eat the job.

 

The stem corrosion issue is surely addressed! However two things bother me about that design:


1) the sensor is pushed a good 1/2" toward the wheel centerline and that scares me some. The tire installer could put a hurtin' on that sensor because it's hanging out there like a lollipop on a thin stick instead of being wedged tightly into the rim corner.
2) centrifugal force will put lateral load on the stem where it passes thru the rim hole. It is not firmly clamped into place with a pinch bolt and nut as other designs. This might not be a problem with a minivan that sees max speeds of 70mph, but I sure as heck wouldn't want one of these on my Vette lol.

 

FWIW:
For the 2011 and up models, Chrysler changed to the same style sensor as the Schrader (Mopar #56029398AB).

Schrader also has sensor number 20398 for the 2011 and up models.

George

 

I was just asking if I can replace sensors myself I'm a certified mechanic I just don't work on tires, I can get a set of 4 non programmable sensors for as low as $70, If that didn't fix the problem that means I will have to live with the problem since I know tires are safe, there is no way for me to pay dealer for fixing it, but if they charge less than $50 to tell me what's the problem I don't mind, I bought the van with the light ON, Bought it for $6k it was a deal that I couldn't pass up.

 

I replaced all of my 09 caravan sensors with the Schrader 28434 after one of the retaining nuts on the original sensors fell off and left my wife with a flat tire far from home, ~ two years ago. The other three aluminum retainers(hex collar) were corroded / cracked - thanks to NY salt. The schrader valves (rubber and brass) required no programming and I have not had a bit of trouble with them. I never plan on having aluminum tpms sensors again!

 

OK George and Dan, I'm on board too with Schrader's rubber pop-in TPMS stem design with no retainer nut since Dodge has adopted them to 2011 and up vehicles, including their higher speed V8 cars.

However according to Schrader's cross reference guide, their #28434 will not work on my 2008 Grand Caravan and I don't see an alternate rubber stem unit in their parts listing that will. Schrader is still selling a metal valve stem unit for my van. My OE part#56053031AD is quite common on both 2008 and 2009 Dodge GC.


http://www.schraderinternational.com..._09-16-13.ashx

This is the most popular direct-fit TPMS for my 2008 Grand Caravan. The stem is replaceable and sold everywhere (Dorman#974-000).

http://www.dormanproducts.com/itemde...SEName=974-061
http://www.dormanproducts.com/p-14203-974-000.aspx

 

That is the Schrader's Ez-Sensor catalog you're looking in. Schrader's full catalog lists the #28434 sensor for the 2008 Grand Caravan (see page 26):
http://www.schraderinternational.com/~/media/Schrader/Files/Document Library PDFs/North America /Schrader TPMS 2013_Catalog_11-13-12.ashx

George