Tire Sizing & Fitment
DOT Tractor Tires: How to Read the Date Code and Tire Age
On DOT tractor tires, the date sits in the last four digits of the code after the letters DOT. The first two digits are the week and the last two are the year, so 0517 means week 5 of 2017. Check both sidewalls, because makers may stamp the full code on only one.
DOT tractor tires sounds like a government form for rubber. It is closer to a birth certificate. Every tire carries a short code on the sidewall, and the last four digits say which week and year it was made. (Yes, your tire has a birthday. No, it will not ask for cake.)
Here is the short version. Find the letters DOT on the sidewall. Read the last four digits. The first two are the week and the last two are the year, so 0517 means week 5 of 2017. We checked this against Pirelli, Nokian’s page on heavy tires, a truck tire guide and NHTSA.
What does DOT mean on a tractor tire?
DOT stands for Department of Transportation. The full code runs 7 to 13 letters and numbers, according to Pirelli. It starts with DOT and then splits into blocks. Nokian’s page on heavy tires adds that the code traces a tire back to its plant, which helps if a defect or recall turns up.
| Block in the code | What it tells you |
|---|---|
| DOT | The marker. Everything after it is the tire’s ID. |
| First two characters | The manufacturer and plant |
| Size block | A short code for tire size |
| Product block (optional) | The maker’s own internal code |
| Last four digits | The week and year of manufacture |
Only the last four digits matter for age. The rest is the maker’s filing system, and nobody invites us to it.
How do you read the DOT date code on a tractor tire?
Take the last four digits. Two for the week, two for the year. Weeks run 01 to 52, with a 53 in some years, says a truck tire guide we read. A made-up layout looks like this: DOT XXXX XXXX 0517. It is not a real tire, just the shape of the thing.
| Date code | Made | Full years old in October 2026 |
|---|---|---|
| 0308 | Week 3 of 2008 | 18 |
| 0517 | Week 5 of 2017 | 9 |
| 0218 | Week 2 of 2018 | 8 |
| 3618 | Week 36 of 2018 | 8 |
| 2524 | Week 25 of 2024 | 2 |
A date with only three digits means the tire was made before 2000, when a different system was used (Pirelli). That tire is at least 26 years old today. Age is just a number. On a tire, it is four of them.
Where is the DOT code on a tractor tire?
On the sidewall. Makers only have to stamp the full code on one side. If you see DOT followed by nothing, turn to the other side, as NHTSA says to check both. Wipe the mud off first. Mud hides everything, including your tire’s age.
The date is always the last four digits of the full code. Do not mistake a mold number or a partial marking for it. If you are on a mounted tire, a flashlight helps with the inner sidewall.
Older farm tires can be stubborn. On a Yesterday’s Tractors forum thread, one owner could not decode the number on his 14.9-38 tires, and a former tire buyer for a tractor plant said each maker used its own code and placement. If yours will not decode, send us a photo. Our tractor tire size guide covers the other sidewall markings.
How old is too old for a tractor tire?
The honest answer: nobody publishes one number. Here is what each source we read says.
| Source | What it says |
|---|---|
| NHTSA | Some vehicle and tire makers recommend replacing tires 6 to 10 years old, whatever the tread. You cannot tell a tire’s age by looking at it. |
| Pirelli | No hard replacement date. Use, alignment and storage all matter, and aging cannot be avoided. |
| Truck tire guide | No federal age limit. Maker and fleet policies commonly run 6 to 10 years from production. |
| Nokian | Rubber deteriorates over time, even when the tire is not in use. |
| Forum owner | Tractor tire age matters less than road tire age. Run them until bald or the sidewalls split. |
The forum owner is one voice, so weigh it as one. Our rule of thumb, built on the 6 to 10 year range: read the date at 6 years, look hard at the sidewalls, and ask the maker or us as it nears 10. Cracks tell you more than the hour meter does.
Why check the DOT date before you buy used tractor tires?
Our opinion: read the date before the tread. NHTSA’s own example, 0308, is a tire made in the third week of 2008. That tire is 18 years old this year, and NHTSA says you cannot judge age by eye. Deep lugs do not make rubber younger. Tread carefully with used tires.
Ask the seller for a close-up of the DOT stamp with the whole code in frame. We get photos from suppliers on request, so add the stamp to your list. Our used tire inspection guide has the full checklist, and the used tractor tires page shows what we source.
New tires age on the shelf too. Nokian’s page says to confirm a tire has not been stored for long after production. A date check takes ten seconds and costs nothing.
When don’t you need to worry about the date?
Less often than the panic suggests. We would rather tell you now than after the quote. (Time flies. Tires, mostly, just crack.)
- The tires are a few years old, the sidewalls are smooth and the pressure holds. Read the date, write it down, move on.
- The only problem is a puncture. Get it repaired locally.
- The tire looks soft. Check pressure before you blame age. Our tractor tire pressure guide shows how.
- You are not buying anything. Reading a date costs nothing and needs no quote.
If a date is old, or you cannot find one, start a quote with a photo of the stamp. Browse our tractor tires and agricultural tires in the meantime. We will tell you if you do not need to buy, even if it costs us the sale.
More tractor tire guides from us:
- Snow Tires for Tractors: Do You Need Them or Chains?
- 23×8.50-12 Tires: Size, Rim Width, Ply and What They Fit
- Firestone Tractor Tires: Who Makes Them and Which Line Fits
- R2 Tractor Tires: What R-2 Rice and Cane Tread Is For
- R3 Tires: What They Are, Where They Work and When They Don't
- Trelleborg Tires: Who Owns Them, What They Make and Sizes We List
- 10-16.5 Tractor Tire: Size, Ply Ratings and What It Fits
- Tires for Compact Tractors: R1, R3 or R4 Tread?
- How to Measure Tractor Tire Size: Width, Diameter and Circumference
- R14 Tractor Tires: Hybrid Tread, Sizes and R4 vs R14
- R1 Tractor Tires: What They Are and Where They Work
- Garden Tractor Tires: Sizes, Tread and How to Choose
- Lawn Tractor Tires: Sizes, Tread and How to Choose
- R4 Tractor Tires: What They Are and When to Use Them
- Firestone Tractor Tire Size Chart: Every Size by Model
- Farm Equipment Tires: Which Type Fits Which Machine
- Rear Tractor Tires: Sizes, Tread and How to Pick a Pair
- Goodyear Tractor Tires: Who Makes Them and What Changed
- Titan Tires: Who Owns Titan, Where It Makes Them and Are They Good
- Front Tractor Tires: Which Tread, Size and Pair to Buy
- Who Makes BKT Tires? Owner, Factories and Where They're Made
- Big Tractor Tires: How Big They Get, What They Fit and Cost
- How Much Does a Tractor Tire Cost? Real Prices by Size
- IF vs VF Tires: What They Mean and When to Choose Them
- Tractor Tire Pressure: How to Set It for Load and Speed
- How to Inspect Used Tractor Tires Before You Buy
- R1 vs R1W Tractor Tires: What Is the Difference?
- Radial vs. Bias-Ply Tractor Tires: Which Should You Choose?
- Tractor Tire Size Guide: How to Read Every Number on the Sidewall
- Tractor Tire Types Explained: R1 vs R2 vs R3 vs R4
Send us a photo of the DOT stamp on WhatsApp. We’ll read it with you. We’ll probably make an age joke. The joke is free, and unlike your tires, it does not expire.
Questions
What does DOT mean on a tractor tire?
DOT stands for Department of Transportation. The code that follows identifies the plant, the tire size and, at the end, the date the tire was made. Only the last four digits tell you its age.
How do I read the date on a tractor tire?
Find the full DOT code and read the last four digits. The first two are the week and the last two are the year. So 0517 means week 5 of 2017.
Where is the DOT code on a tractor tire?
It is on the sidewall. Makers may stamp the full code on one side only, so check both sidewalls. Wipe off mud first, and use a flashlight on the inner side of a mounted tire.
How old is too old for a tractor tire?
No source we read gives one number. NHTSA says some makers recommend replacing tires at 6 to 10 years regardless of tread. Read the date at 6 years, inspect the sidewalls for cracks, and ask the maker or us as it nears 10.
Do tractor tires expire if they are never used?
Rubber deteriorates over time even when a tire is not in use, according to Nokian. Pirelli adds that aging cannot be avoided entirely. Storage, sun and use all change how fast it happens.
What if the date code has only three digits?
A three-digit date means the tire was made before 2000, under a different system. That tire is at least 26 years old today. Inspect it closely and ask the maker before you trust it.
Can I tell a tire's age by looking at it?
No. NHTSA says you cannot tell a tire's age just by looking. A tire with deep lugs can still be old, so read the DOT code.
Does the DOT date matter on used tractor tires?
Yes. Age is the one thing tread depth cannot show. Ask the seller for a close-up of the whole DOT code. We get photos from suppliers on request, so add the stamp to your list.