Tire Date Codes: Read the Manufacture Week and Year Without Guessing an Expiry Date
A modern DOT tire date code gives a manufacture week and year, not an expiry date. Read the last four digits, keep the full identifier in your record, and separate manufacture from purchase and installation. This U.S.-focused guide explains how to make a useful note without guessing whether a tire is safe from its age alone.
1. Read the last four digits, not a guessed calendar date
For a modern U.S. DOT Tire Identification Number, NHTSA explains that the final four digits identify the manufacture week and year. Its example 0308 means the third week of 2008. The full marking may appear on only one side, so a partial view is not enough.
For a practice example, split 2424 into 24 / 24: week 24, year 2024. It does not mean 24 April, a purchase date, or a month numbered 24. Do not estimate an exact day from this code. Copy all four digits as a group before separating their meanings.
2. Make a record without guessing at hidden digits
Park before inspecting. Photograph the legible marking and note which tire you are recording: left front, right front, left rear, right rear, or spare. If a sidewall is hard to see, ask a tire service professional to identify the full marking. Do not crawl beneath an unsupported vehicle or remove a wheel just to finish a note.
| Record | What to write | Why it helps |
|---|---|---|
| Tire position | For example: right rear | Prevents mixing the four tires together |
| Brand and tire line | Copy the actual sidewall wording | Gives a service shop useful context |
| Full TIN | Copy the complete visible marking | The date portion alone is not the full identifier |
| Date portion | Four digits, then week / year | Keeps the raw evidence beside your reading |
| Unclear characters | Mark them as unclear | A blank is better than an invented digit |
3. Manufacture, purchase and installation are separate dates
A receipt can tell you when you bought a tire; your service record may tell you when it was fitted. Neither should replace the manufacture code in your notes. Keep separate fields so that a tire purchased recently is not automatically treated as recently manufactured.
In a fictional example, a driver buys a tire in 2026 and records a date portion of 2424. The note should retain both facts: purchase in 2026 and manufacture in week 24 of 2024. That example does not establish whether the particular tire is suitable for service. It shows why the dates should not be merged into one number.
4. A date code does not certify a tire as safe
NHTSA says aging cannot be assessed simply by appearance. It also notes that some tire and vehicle manufacturers recommend replacement at six to ten years regardless of tread. That is a range of manufacturer recommendations, not one universal expiry rule. Check the guidance for your actual tire and vehicle.
Damage, irregular wear, pressure loss, noise or vibration also deserve professional attention. A recent date does not cancel a fault; an older date needs context rather than a guessed automatic pass. Do not use an age note to justify continuing to drive on a tire with a visible bulge or other concerning damage.
5. Use the note to ask a better service question
Bring the sidewall photo, manufacture code, purchase or installation record if available, and a description of any problem. Ask which manufacturer age guidance applies, whether the tire needs further inspection, and what the shop can or cannot conclude from the available information.
| Less useful question | More useful question |
|---|---|
| It looks fine; is it good for years? | What condition checks and maker age guidance apply to this tire? |
| I bought it recently, so it must be new? | How does the manufacture code compare with my purchase record? |
| The date is hard to read; can I guess? | Can you identify the complete TIN and date portion? |
Check each fitted tire and the spare separately. They do not have to share a manufacture date, and one clear photograph should not stand in for the entire set.
6. Frequently asked questions
Does 2424 mean a month and year?
In this four-digit example it means manufacture week 24 of 2024, not a month.
Is the four-digit date the whole DOT TIN?
No. Keep the full legible marking as well as the date portion in your record.
Does a tire expire automatically after six years?
Do not turn the range noted by NHTSA into a universal deadline. Follow the actual tire and vehicle manufacturer guidance and condition assessment.
Can a newly purchased tire have an earlier manufacture year?
Purchase and manufacture are different events. Record both rather than assuming they match.
7. Source and related tire care
NHTSA TireWise: Tire Aging supports the date-code explanation and the distinction between age and condition. The recording table and fictional 2424 example are learning aids created for this article.
Read the door-placard cold-pressure guideBridgestone: Check Tire Condition and Age also explains the week/year date code and advises professional inspection when condition is uncertain. Follow the guidance applicable to the tire and vehicle you actually use.
Information checked: 3 October 2026.
The cover illustration was created with AI; the explanatory diagram was composed for this article.
댓글
댓글 쓰기