Determining Tire Age

I have read quite a few posts lately dealing with tires falling apart etc... while drving down the road. This can sometimes create a dangerous situation for the driver or for anyone following behind the truck. Here's an exerpt from a Military Tire Manual on how to determine the age of your tires. Enjoy!

How to Determine the Date of Manufacture of Off – Road and Highway Tires
The following is a guide to reading the date of manufacture of off-road and highway tires
sold by our major suppliers: Denman, Bridgestone/Firestone, Goodyear, Cooper, General
and Michelin. Each manufacturer, with the exception of Michelin, has molded a serial
number into the sidewall of each tire. However, there are some differences among them,
which are noted below:

DENMAN: Denman uses a serial number, the last 3 digits of which constitute the date of
manufacture. These last 3 digits are to be read just as a DOT Code, i.e., 1st 2 digits =
week of manufacture and the last digit = the year of manufacture. For example, serial
number 1234527 = a date of manufacture of the 52nd week of 1997.

BRIDGESTONE/FIRESTONE: Bridgestone/Firestone serial numbers are normally 9
characters in length and usually begin with a letter (usually the letter Y). The second
position of the serial number indicates the year of manufacture. For example, a tire with
serial number Y61234567 was manufactured in 1996.

GOODYEAR: Each Goodyear off – road tire has a serial number beginning with the
letters MJ or MC. The last 3 numbers of the serial number indicate the week and year of
manufacture. For example, a tire with serial number MJ1234567236 was manufactured
during the 23rd week of 1996.

COOPER: Cooper brand off – road tires, have a ten-digit serial number. The last 3 digits
of the serial number indicate the week and year of manufacture. For example, a Cooper
tire with serial number 1234567205, was manufactured during the 20th week of 1995.

GENERAL: General uses a 9 position alphanumeric code, with the last three characters
representing the month and year of manufacture. General is different from the other
manufacturers in that the seventh character, representing the month of manufacture, is a letter, rather than a number. Using this code, the first letter of the Alphabet represents the first month of the year and the second letter of the Alphabet represents the second month, etc.. The last two characters are numbers representing the year of manufacture. For example, a General tire with the code 01479BK96, was manufactured in the 11th month, since the letter K is the 11th letter of the Alphabet and the year of manufacture is 1996, since the last 2 numbers are 96.

MICHELIN: Michelin has no serial numbers on it’s off – road tires that would indicate
the date of manufacture. SUGGESTION: Look for a DOT Code. 14

TITAN: Titan uses the DOT Code system for all of its tires. Therefore, prior to 1 January
2000, the last three digits of their code for both off and on road tires indicate the week
and year of manufacture. For example, a tire with the DOT Code DOT CH EV HU4 501
was manufactured during the 50th week of 1991. All Titan tires produced since 1
January 2000 reflect the new DOT coding system. Therefore, the last 4 digits for those
tires reflect the week, year and decade of manufacture. For example, a tire with DOT
Code DOT V5 2J EFT 4600 was manufactured during the 46th week of the year 2000.

DOT CODES: All highway type tires sold in the United States must have a DOT (Dept.
of Transportation) Code molded into their sidewalls. The DOT code is alphanumeric, is
composed of 13 characters and always begins with the letters DOT. The last 3 positions
of this code indicate the week and year of manufacture. For example, a tire with the DOT
Code DOT CH EV HU4 501 was manufactured during the 50th week of 1991.

DOT CODE UPDATE:
Starting with year 2000 production tires, an additional number was added to DOT Codes.
As a result DOT Codes are now 14 characters in length instead of 13.This change has
enabled tire manufacturers to show the decade of manufacture. For example, a tire with
DOT Code DOT V5 2J EFT 4600 was manufactured during the 46th week of the year
2000.

Thanks, Chris - very informative. I think this may be a "must have" to print out and bring when tire shopping at MV shows and MV graveyards, hopefully will prevent a few of those nasty tire blowouts like you see here every so often.

With trucks the age of our fleets how do we know that they were made in the 90's versus 80's 70's or 60's ? I just think the one digit date is hard to tell I think dry rot is the best way to tell and should be a sign to start saving for new tires and not to overload the ones with the cracks. I have cracks on a lot of my trailer tires and they still work fine even under load. I know I am taking a risk but I have seen tires over 30 years old still working on a dump truck.

Here's the source: https://www.themotorpool.org/TireCatalog 2005 Updated.pdf if anyone is interested.

You can check for presence of tread wear indicators...makes em relatively recent.... and the plethora of warnings molded in... more warnings ...less age... aka newer... RAM

Chris:
Thanks I called them and they are sending me the tire TM I will try to post it to the site they say replace tires at first sign of cracking something I have not done

One thing that I have on my site are several pages concerning tires, mostly info for folks running 900x16 or 1100x16 (or radials of that size) for M37/M715/Power Wagons, but some of it crosses over to other M series stuff as well... I have a link to a site that lists all the DOT codes and which plant they are assigned to, Tire and Rim Association pages showing dimension data for Rims, OSHA and DOD manual information on inspecting and changing tires, etc.
It could be better organized, but the main link to it all is located at:
http://www.garbee.net/~cabell/tires.htm

The shortcut link to the DOT codes is:
http://www.harriger.com/tires.htm

TM 9-2610-200-14, Pneumatic Tires and Inner Tubes (September 2000) and TM 9-2610-200-20, Pneumatic Tires, Inner Tubes, and Radial Tires (February 1977) may be found on the Olive-Drab website in PDF form. Page with the links to these two manuals is:
http://www.olive-drab.com/od_mvg_technical_reference.php3

Good deal David. I appreciate you taking care of that. Good links Cabell. Thanks.

Sticky!! Edited original post for easier reading.

All the tires on my WWII Ford jeep are dated 1965, they are 600:16s.
The tires were made for the Marine Mighty Mite. I found them at a Vol. Fire Dept. They were an update kit for the Mighty Mite jeep. The kit was a spare tire holder. It also had a spare tire. I purchased all 5 kits, just for the tires. The kits were sealed in wooden crates so, the tires had never seen sunlight.
They are still on my jeep.
One of the few, Frank

That's really cool Frank. How are they holding up so far?

Just great!!
The only problem I had was, I also used the tubes that were in the crates, they did not last long(as in did not even hold air!). When Carbee comes down in a couple of weeks, I will get him to snap a few photos showing the dates.
Tonight I will post a funny story about the combat rims on my 43 jeep that I think every one will enjoy.
One of the few, Frank

if its any help my tyres are all dated Or shud i say the nes iv taken off my reo now has a new set of boots and they are titan... new n shiney

TM 9-2610-200-14 has been uploaded to the site.

A little command on tires: The military tires are made to last very many years (weather US-made or Germany made), even so called cracks in the sidewall not necessarily mean, they are unusealble. Main killer for tires is sunlight. I melts the wax in the rubber out. Than the tires more easily overheat than usualy, especially on too low tire pressure. The military given tire pressure is a compromize of tire load, road performance (they normally drive at 35 to 40 mph (not in Germany, the US Army speed here is as fast as possible, the tires blow often enough)) and minimum Off Road performance. To European understanding the standard non directional tread of the military tires looks cool, but is no good on wet roads or on tramway rails for example. Braking behaving is poor. Austrian or Swiss tires are the same, so not only a US problem.
Normally we look for tires beeing not over 15 or 20 years old (military pattern) and increase the tire pressure at least 15 to 20 PSI. On trailers it is not that severe, but we use higher pressure.
Simply, we try to use tires as new as possible. So sometimes you have to buy a new set, even when the old set looks still very well from the rubber left.
European tires are marked with a three digit number from the 1980 until 1990. Then they found: to many old tires, so from 1990 they added a triangle behind that three digit number. Since 2000 the number is four digits. The first two is the week of manufacture, the third or the last two are the year.
Modern tires also carry a load and speed index. With the according lists you easyly find the permissable tire load and the maximum speed permitted for the tire. The lists give you also the minimum tire pressure. Ask your dealer, if they sell European tires, they should have the lists/technical tire descriptions.
For example, the CUCV Blazer requires a LRC / 6PR / 100N minimum tire reading. The door label says 29 KPa. I used 35 KPA and the truck run very well on it with a very long tire live (over 70,000 miles). 29 KPa was for my understanding too soapy, even 29 KPA was correct for a maximum speed not exceeding 65 mph (official speed limit for the US Army in Germany is 55 mph for any kind of vehicle). But I normally drove 75 mph on the Autobahn.
My M715 says 8 PR, TP front 25, TP rear 45 PSI. I newer used that low pressure. With the actual tires, which are 10 PR, I once used 3.5 KPA front and rear for comfort, now I use 5 KPa front and 5.5 KPA rear. That makes lower fuel consumtion, easyer steering, better feeling overall, same comfort. A M715 chassis is not comfortable at any tire pressure, I test since 26 years!

I'm not sure if I should be posting a new thread or not, but I was confused so here goes. I read that the DOT date codes go to 14 characters after 2000. I have a Titan tire which has a 14 digit code, but if what I read is right (week/week/year/year) my tire is from 1987... That doesn't make sense, it says "9487" but 1987 would be "947", wouldn't it? How old is this thing really? Thanks for the help

Look what is placed in the oval, only! After 2K it's 4 digits: first two = week; second two = year.
Or post a pic of what you see and we may be able to help.


G.

Thanks everyone for the info.

Here are three codes from tires I just bought, the one that says MILITARY is the one I am confused with. The other two seem to be from 2000 and 1999 (judging by the triangle). Is it safe to run these? Not many cracks at all, and they would look better than the silly road tires on it now...