Author Topic: For PagodaFest - Check your tires!  (Read 2360 times)

Rick

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For PagodaFest - Check your tires!
« on: August 29, 2019, 20:54:08 »
With PagodaFest fast approaching, it is important to be sure our cars are in proper and safe condition.  I expect there will be SL’s which have spent much time parked in a garage and probably not seen many recent miles over a number of years. For this event, these cars may be required to drive high-speed freeway miles in a short few days.
 
Specifically, please check the age of your tires!  Any tire which has reached approximately seven years old, should be replaced (some sources say ten years, but that is pushing it).  I have seen way too many gorgeous classic cars suffer severe fender and structural damage from tread separations and exploding older tires.  In the old days, having a low-mile, always garaged tire with no sign of sidewall or tread deterioration or cracking meant you were good to go.  This is no longer true with newer steel-belted tires!  Age becomes a primary consideration beyond visible rubber condition, storage or miles.

In the old days, tires were constructed with fabric belts.  These belts were molded firmly into the tire and would only be a problem with rubber cracking which allowed oxygen to deteriorate the fabric.  In the “old days” a tire would most commonly blow out a sidewall, and sometimes a location on the tread itself and then it would quickly lose air.  Again, this was generally trackable to the age of rubber and cracking visible on the surface.

Things are different today with our steel-belted tires.  The steel belting does not bond as well to the inside tread rubber as did the fabric cords of days past.  The constant pressure of tire inflation is continually and slowly pulling the steel belt apart from the inside rubber it was originally molded to.  Industry estimates that after seven years of “in-use” time (in-use time is defined the time a tire is inflated with air pressure and has nothing to do with miles driven or how it is stored), a tire has lost 40% of its strength, or more.

When these older tires are exposed to higher speeds, the chances of a dramatic tread separation goes up exponentially as compared to a newer tire. This separation is not just a loss of air (like would have been more often experienced with an older fabric style tire).  The tread separation can be sudden and can cause major fender and structural damage as well as a potential loss of control.

And yes, that beautiful, crack free, fresh appearing, original spare which has always stored in the trunk under pressure (since 1970?) is a tread seperation ready to happen. I have seen these types of spare tires shred within 10 miles of being installed.

You can read the date of manufacture of your tire per its DOT code on the sidewall.  Tires made after 2000 have a four-digit date code (see picture).  This code was imprinted only on the inside of the tire sidewall until approximately 5 years ago when it was placed on both sides. A three-digit date code means the tire was produced somewhere before year 2000, but you have no way to know which decade it was made?  If you find a three-digit date code, the tire automatically too old and must be replaced!

Take the time to verify you have safe tires, please. It is not worth a tire explosion to ruin a trip.  Tires are not all that expensive compared to what you can lose.
« Last Edit: August 30, 2019, 04:39:18 by Rick »

Mike Hughes

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Re: For PagodaFest - Check your tires!
« Reply #1 on: September 02, 2019, 23:52:25 »
Thank you, Rick, for the timely reminder of the adverse safety aspects of riding on perfectly good looking older rubber. 

Several years ago, after winning his class and also the "People's Choice" award, an acquaintance died on the way home from a car show in his perfectly restored Sunbeam Tiger, a car he had bought new when he came home from Viet Nam in 1966.  As far as he was concerned his tires were "almost brand new."  He had driven the car less than 2500 miles since he restored it 14 years earlier, basically to and from regional car shows.  Maryland State Police ruled the cause of the single car accident on a straight two-lane road with ample shoulders on a clear sunny day was tread separation.  If you are riding on older tires, you are riding on four time bombs.  Your car doesn't deserve such a fate and neither does your family, 'nuff said.
- Mike Hughes  -ô¿ô-
  1966 230SL Auto P/S
  Havana Brown (408)
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beachbear

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Re: For PagodaFest - Check your tires!
« Reply #2 on: October 01, 2019, 07:22:39 »
Oh my gosh, this reminds me that God protects fools and babies! I was no baby when I pulled our 280sl out of storage in New Jersey after sitting for almost four years. My wife and I took it on a small road trip before putting it on a trailer. I shudder to think of the distance and the speeds between when I started driving it and when I learned there was a timed life span for tires! We rolled on four fully treaded time bombs!
David White
'69 280sl automatic, 3rd owner since '82

Cees Klumper

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Re: For PagodaFest - Check your tires!
« Reply #3 on: October 01, 2019, 11:48:54 »
When I first bought my Pagoda in 1999 it had on it Michelins that looked in great shape. Soon after getting it, driving on the highway one day I heard a bang and upon checking found a large piece of tread had just flown off one of the tires. No damage to car or occupants, but it could have ended differently. Got 4 new Pirellis the same day.
In Europe we often see caravans and trailers by the side of the road with blown tires. Same issue: tires look fine but, due to being used very little, too old to be safe.
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

doitwright

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Re: For PagodaFest - Check your tires!
« Reply #4 on: October 01, 2019, 21:16:49 »
When I acquired a 220SE Coupe last March it had what appeared to be new tires. Still had the fine rubber spikes all around. The receipts that came with the car showed that it received new tires in 2007. I took the car in to Discount Tire and they confirmed they were installed in 2007. I replaced them. Just not worth the risk.
Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Originally Light Ivory - Now Anthracite Gray Metallic

rwmastel

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Re: For PagodaFest - Check your tires!
« Reply #5 on: September 06, 2023, 19:40:31 »
Wise advice from 4 years ago.

Does anyone have a detailed "road trip departure checklist" that they would want to share with fellow travelers?
Rodd

Did you search the forum before asking?
2017 C43 AMG
2006 Wrangler Rubicon
1980 450SL
1966 230SL