I work for a Chrysler Dealership, just came back from service, and was talking to a crossfire owner who also had his nitro in for service. He had Nitrogen put in his tires, and we replaced his caps with a Metal Chrome cap with a green top to denote that the tire was filled with nitrogen. He went to check his pressure and the Chrome Cap would not come off. So he proceeded to get a wrench and started to turn Cap to get off and snapped the whole stem off. Well Tire went flat and had to be towed. We found two other caps on his car that had corroded (SP). After talking to service they have had others come in with the same problem. Thought I would put this out to everybody, if you have the Chrome Metal Caps Get rid of them and go to a Aluminium cap with a rubber coating on the inside, or plastic, or the orginal caps that came with the car. We did replace his Valve stem, due to the fact we installed the Chrome Caps. Needless to say the least we do not have a Chrome cap anywhere to be found. Hope this helps someone before you snap off a Valve Stem.

 

Thanks for the Info!!! Was thiinking about putting Nitrogen in my tires.
thanks

 

Yes, thanks for the information. I received a coupon in the mail for a special discount on the nitrogen. I'm still considering it right now.

 

Interesting. I've read here where 'Never-Seez Anti-Seize & Lubricating Compound' will prevent the chrome valve cap issue. I haven't used it yet. Maybe I should.

 

i dont' think the nitrogen caused his issues. you would think the lack of oxygen would prevent oxidizing effects.

 

I had nitrogen put in my tires the last time I had my oil changed at the dealer. Here's the company http://www.whynitrofill.com

I had a choice between the green caps or chrome with a white insert that said "nitro" - I chose the chrome.

Been about two months and I haven't had a problem yet.

I'll keep a close eye on them now.

Thanks

 

I would agree, the Nitrogen, itself, would not cause corrosion. Maybe it was due to road-salt or very cheap caps??

 

Tires - Nitrogen air loss study

Filling tires with nitrogen rather than air is becoming a common practice in the replacement tire market. This service offers tire dealers another avenue for making money while also promoting safety. The claimed safety benefits often include the potential for reducing air loss compared to an air-filled tire. Maintaining proper inflation can help prevent tire overheating; promote optimum tread life; and reduce rubber aging and wheel corrosion. The use of nitrogen in large truck fleets and the commercial tire industry are well documented and support these claims.
The National Highway Traffic Safety Administration (NHTSA) has seen reduced aging of tires filled with nitrogen. Though the data does support that passenger car tires could benefit by all the claims made for nitrogen, tire manufacturers say that they already design tires to perform well with air inflation. And while nitrogen will do no harm, manufacturers say that they don't see the need to use nitrogen, which generally adds $5 or more per tire charge.
Consumer Reports wanted to find out if nitrogen is worth the price, so we purchased a Nitrogen Inflation System and checked out how well the inflation held up over a one year period. We evaluated pairs of 31 tire models of H- and V-speed rated, all-season tires used in our tread wear test from 2006. We filled one tire per model with air and the other with nitrogen. The test was quite simple: fill and set the inflation pressure at room temperature to 30 psi (pounds per square inch); set the tire outdoors for one year; and then recheck the inflation pressure at room temperature after a one year period.
The tires were filled and deflated three times with nitrogen to purge the air out of the tire cavity. We also used an oxygen analyzer to be sure we had 95-percent nitrogen purity in the tire--the claimed purity limit of our nitrogen system, which generates nitrogen gas from ambient air.
The test started on September 20, 2006 and the final measurements were taken on September 20, 2007. The results show nitrogen does reduce pressure loss over time, but the reduction is only a 1.3 psi difference from air-filled tires. The average loss of air-filled tires was just 3.5 psi from the initial 30 pressure setting. Nitrogen-filled tires lost an average of 2.2 psi from the initial 30 psi setting. More important, all tires lost air pressure regardless of the inflation medium, so consumers should check their tires' air pressure routinely. No evaluation was done to assess the aging claim.
Bottom line: Overall, consumers can use nitrogen and might enjoy the slight improvement in air retention provided, but it's not a substitute for regular inflation checks.
--Gene Petersen

 

Retalked to the Crossfire Mechanic at work. He is under the impression that the Chrome Caps and the Stem some how get corroded and then the stem being Aluminum breaks when the pressure is applied with a Wrench. He advised just to remove the Chrome Caps and either go with OEM Caps or the new aluminum caps with the rupper inserts. Naturally our dealership charges for the good Valve stem Caps. Nitrogen in your tires is your choice, some people like it some do not. I just wanted everybody to know about the Chrome Caps.

 

Sounds like galvanic action at work. Two different metals in contact with each other. Add some salt water to the mix and you have a battery!!

 

"He went to check his pressure and the Chrome Cap would not come off. So he proceeded to get a wrench and started to turn Cap to get off and snapped the whole stem off."

This happened to me. Tire shop put a new sensor/stem in for $130 and told me the other 3 stems and sensors were in a bad way and they would not touch them. They advised me to hit on Chrysler Corp and try get free replacements due to a design flaw. Anybody tried this? Success?

Anyone know of a cheaper source for valve/sensors?

Thx,
Howie.
04 Coupe

 

I don't use nitro but have chrome stems on both xfires. I keep them finger tight. Check them this weekend and no problems after 8 months on one and 6 months on the other. We don't have salty roads though either.

 

Forgot to mention, the tire shop suggested nitrogen to slow the internal corrosion to the sensors, and also to keep the pressure more stable during temperature swings. (Here in salty Chicago, we had 30F one day and 70F the next a couple of weeks ago!). They wanted $5 per tire, which was cheap, I thought, but as I said, when they looked at the other valve stems they wouldn't even try to put any pressure on them.

Also forgot to mention that the previous post was my first to the forum, and I'm really glad you experienced guys are around.

It's a stock 04 Coupe, Alabaster, with 21k miles - wish it had more power, so if I can persuade the wife, an SRT-6 is on the horizon.

I put All Season Eagles on it just before winter as the other tires (FS?) weren't going to get me anywhere in snow.

Hope to be a regular now,
Howie.

 

Welcome! Let your wife drive an SRT6 and you'll have no problems persuading her.

 

I totally agree ! If you're gonna use "Chrome valve stem caps" be sure to apply just a dab of "Never Seez" on the threads of the stem, it won't take much. Then finger tight the caps to the stems, remember to check that the rubber seal inside the cap are in place.

Just my Dos Centavos !

 

I agree with Utah12 - two disimilar metals working together to corrode each other.
Were/are the chrome caps chrome on the inside too - threads etc?
If not, that's where the two metals are reacting against each other.
If the caps were chrome all over you wouldn't have the problem.
Also, two different metals = two different expansion rates = problems.
It's all in Corrosion 101.

 

I really don't believe that two dissimilar metals will be much of the issue for those that don't drive on salty roads. I suspect this was more of an issue where they put the caps on too tight and road salt
excelorated the galvanic corrosion.

First of all, chrome is a plating and not a metal. And, aluminum and steel (chromed or not chromed) are very close to each other in galvanic series. Metals near each other in the galvanic series have little effect on each other. Generally, as the separation between metals in the series increases, the corroding effect on the metal higher in the series increases as well.

 

Chrome is indeed normally applied to parts as a plating. It IS a metal (see: http://www.lenntech.com/Periodic-cha...ents/Cr-en.htm). I would be hesitant to put a film coating on my valve stems in order to use a different metal cap on the aluminum valve stems. I wouldn't want to contaminate the valve stem with too much coating, so the coating might not provide adequate protection over a long period of time.

The difference in the electrical potential of two metals in contact with each other indeed causes the transfer of charges between the two different metals, hence, corrosion from the "galvanic" process. The process is accelerated by having moisture between the two metals. Sacrificial cathodes are used to protect buried and coated pipelines because this charge transfer is well understood in the pipeline industry. As long as I am vulnerable to pilfering thieves, I'll use cheap, black, plastic caps to keep dirt out of the stems. I discovered three missing caps today and will order OEM replacements to keep in storage until I frequent more secure locations.

 

This happened to my friend's crossfire. We broke the valve stem on the first tire.

We then removed the other wheels and very carefully used a dremel tool to completely grind the caps off.

Saved $300+

 

Thanks for the notice. I just got nitrogen installed, and I'm pleased with the result. However, I will be using plumber's teflon tape to prevent corrosion from freezing the cap to the stem. It really works in the plumbing trade.