Old tires

[Guest Wayne77590]

How old are your tires.

Look at the writing on the sidewall of the tire. you should see the word DOT followed by a series of numbers.

The last four numbers in that series is the week and year of manufacture. Example 1099 would be the 10th week of 1999.

A lot of tire dealers just don't think about rotating their stock. So the tire the pull for you (the technician putting the tire on) could be pulling from an area that has tires 5 years or older.

Ask to check the tires. look at the number, and if it is not within a date range acceptable for you, refuse the tires and ask for some that are acceptable. Tires that are more than 5 years old should not be used.

Here is some information from the NHTSA.

And here are some information facts from Michelin

EDITED: The Maintenance and Training videos are very informative.

Edited Two: There are some documentation that indicates that tires manufactured before 2000 had a 3 digit code instead of a 4 digit code. I don't know who the exact authority is but the NHTSA site above only mentions the 4 digit code and give the example of 3197, meaning 31st week of 1997. So that shoots the 3 digit code before 2000 dow the tube.

[stevesandidge@yahoo.com]

good info top, and spot on too!

steve

[tireman9]

As I recall the final week that allowed a 3 digit date code ( wwy ) was about April or May 2000. I seem to recall that 1600 was the change over date.

You will probably not see a 4 digit code ( wwyy ) with a 99 but it is possible that there were some tires made in the latter half of 1999.

Hope this helps.

[donhoward49@hotmail.com]

RE: DOT code dating. This is great info for a newbe like me. i just bought a 99 Winnebago with 49,000 miles on it. My DOT is 368. As i understand it that is the 36th week of 1998. So they are the original Goodyear tires on the coach. I am in discussion with the dealer to get some help on replacing the tires as someone should have seen this and not sold the coach with old tires. I like the idea of replacing two tires per year but i wonder if in this case i should replace all of them?

great info guys. thanks

[wolfe10]

RE: DOT code dating. This is great info for a newbie like me. i just bought a 99 Winnebago with 49,000 miles on it. My DOT is 368. As i understand it that is the 36th week of 1998. So they are the original Goodyear tires on the coach. I am in discussion with the dealer to get some help on replacing the tires as someone should have seen this and not sold the coach with old tires. I like the idea of replacing two tires per year but i wonder if in this case i should replace all of them?

great info guys. thanks

Don,

Welcome to the FMCA Forum.

In a word, YES. 11 year old tires are well past replacement!

Then, after loading the coach the way you will be driving down the road, get all wheel positions weighted (best) or axles weighed (easier, but ASSUMES perfect side to side weight distribution) and go to your tire manufacturer's PSI/load chart for your tire to determine correct MINIMUM PSI. If using wheel position weights, use heavier side on each axle to go to the chart. Add 5 PSI to the minimum for safety cushion. If you only have axle weights, add 10 PSI (as long as it doesn't exceed tire or wheel maximum) for safety reserve AND side to side imbalance.

Unlike car tires, large vehicle tires correct pressure is VERY load dependent and can cover a RANGE of 40 or so PSI.

And when purchasing the new ones, be sure to get ones that are no more than 3 months old, as you will likely be replacing them based on time, not tread wear.

Brett Wolfe

[donhoward49@hotmail.com]

Don,

Welcome to the FMCA Forum.

In a word, YES. 11 year old tires are well past replacement!

Then, after loading the coach the way you will be driving down the road, get all wheel positions weighted (best) or axles weighed (easier, but ASSUMES perfect side to side weight distribution) and go to your tire manufacturer's PSI/load chart for your tire to determine correct MINIMUM PSI. If using wheel position weights, use heavier side on each axle to go to the chart. Add 5 PSI to the minimum for safety cushion. If you only have axle weights, add 10 PSI (as long as it doesn't exceed tire or wheel maximum) for safety reserve AND side to side imbalance.

Unlike car tires, large vehicle tires correct pressure is VERY load dependent and can cover a RANGE of 40 or so PSI.

And when purchasing the new ones, be sure to get ones that are no more than 3 months old, as you will likely be replacing them based on time, not tread wear.

Brett Wolfe