# Tyre valves advice required any experts?



## trek (May 1, 2005)

Just been to change tyres as the old ones are all week 50 / 2007

The tyre dealer started changing and balancing the new tyres and it wasnt until they had done 3 and stripped 2 more that i noticed that the new valve was much shorter that the original

This will be a big problem as i have double wheels on the back so with these short valves i wouldnt be able to check pressures ( already have a single valve extender each side where the double wheels fit together ) 


Now they told me that the shorter valves that they had fitted were more suitable for heavy commercial applications , the longer valves they had were TR418 which they thought wouldnt be correct

But the remaining tyre that they had yet to start on which is original factory fitted is also a TR418 valve 


So any tyre valve experts out there who know anything about these valves 

They were reluctant to fit them as the TR418 is rated at a maximum 4.5 bar cold pressure 

My tyre presures front are 4.2 and rears 4.0 bar fully loaded


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## greygit (Apr 15, 2007)

I would go with the higher pressure valves.


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## trek (May 1, 2005)

Its a dilemma as i agree with you but they are too short and i wouldn't be able to do anything with the tyre pressures on the rear 4 wheels without some sort of valve extender on both pairs of double wheels

And the originals were also TR418


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## Pat-H (Oct 30, 2009)

What about 602HP they are 80PSI max so 5.5 Bar and they are 2inches long.


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## trek (May 1, 2005)

Pat-H you are spot on , i have been looking and can see that the tyre dealer has fitted 600HP's Which are too short so now i have identified the 602HP and this has just been confirmed by you

So now i just need to find a stockist 

Only ones on ebay are in USA 

The tyre dealer reckons it would take their supplier a couple of weeks to get the longer valve though they hadn't told me what it was

May try some other local tyre dealers tomorrow to try and blag 6 of them 



Still think the TR418 would be ok as these were on the original tyres from mercedes and my winter tyres appear to have same rubber stemmed (not metal) valves These tr418 valves are rated at max 65psi 4.5 bar Cold When my max would be 4.2 bar


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## greygit (Apr 15, 2007)

I would have thought most tyre fitting outlet would have valve extenders they were quite commonly used when I was in the trade.


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## Pat-H (Oct 30, 2009)

Longer stems are better if you can use them. Extenders added post balancing will affect the balance and its an additional thing to fail.


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## greygit (Apr 15, 2007)

Pat-H said:


> Longer stems are better if you can use them. Extenders added post balancing will affect the balance and its an additional thing to fail.


I was thinking of the plastic ones as they are very light.


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## Pat-H (Oct 30, 2009)

If using extenders I would always go with the ones that have a wire to hold them. If not a lot of stress is applied to the valve at higher speeds as the extender tries to bend outwards.


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## trek (May 1, 2005)

Many thanks for all your replies 


Valve extenders just don't seem to be available locally And whenever i have needed them in the past i have always had to buy on line ( on my sprinter they have one 60 mm plastic extender on either side ) 

Even truck tyre "specialists " like ATS euromaster commercial depo's dont have them

The final out come was to return to the tyre place and have the shorter high pressure valves removed on the 3 already fitted and them all 6 wheels fitted with the standard pressure TR418 2" long valve 

These were fitted as standard from Mercedes on my original wheels and the same 418's are also fitted to my winter tyre wheels so more than happy to stick with them

The user manual clearly states my max pressure on the front fully laden at cold pressure of 4.2 (For my 518 with my 205/75R16 tyre)

The book then mentions that for any tyre using a pressure of greater than 4.2 bar needs the high pressure valve but these are tyres that are not my size and are for the 4 wheel sprinter not a 6 wheel like mine ( and the next pressure above 4.2 in the manual is 4.5 for a different tyre which is the limit for the TR418 )


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