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The DOT date on your RV tires consists of the last four digits of the DOT code stamped on the sidewall. These digits indicate the week and year of manufacture. For example, “3522” means the tire was made in the 35th week of 2022. Finding and understanding this code is critical for safe towing, especially with heavier rigs like those in the 30 foot rv weight category.
What Is the DOT Code on RV Tires?
The DOT code stands for Department of Transportation, it’s the federal safety standard that regulates tire manufacturing in the United States. Every tire sold in the country has this code molded into the sidewall, whether it’s on a compact 16 ft camper weight trailer or a massive 30-foot camper weight beast.
Here’s the catch: The full DOT code can be on either the inside or outside sidewall of the tire. Sometimes you’ll need to crawl under your trailer or jack it up to see the complete string. The code looks something like this:
DOT U2LL LMLR 3522
Most of it is factory and manufacturer info you don’t need to worry about. What matters is those last four digits.
How to Read the DOT Date on RV Tires (Step-by-Step)
Step 1 – Locate the DOT Code
Walk around your travel trailer and inspect each tire’s sidewall. Look for the letters “DOT” followed by a series of letters and numbers. If you only see a partial code on the outside, check the inner sidewall, it’s often hiding there.
Step 2 – Identify the Last Four Digits
Ignore everything except the final four numbers. These are your manufacturing date.
- First two digits = Week of the year (01 to 52)
- Last two digits = Year of manufacture
Example: DOT ABCD 1221 means the tire was made in the 12th week of 2021 (late March).
Step 3 – Calculate the Tire’s Age
Subtract the manufacturing year from the current year (2026). If the code reads 1221, that tire is now five years old. Even if the tread looks pristine, the rubber has been aging since 2021.
Pro tip: If you see only three digits at the end instead of four, that tire was made before the year 2000. Replace it immediately, no exceptions.
DOT Date Examples (Real-World Scenarios)
Let’s break down a few real codes:
- 2319 → 23rd week of 2019 (early June 2019, now 7 years old)
- 4820 → 48th week of 2020 (late November 2020, now 6 years old)
- 0125 → 1st week of 2025 (early January 2025, basically brand new)
Here’s a frustrating reality: You can walk into a tire shop today and buy a “new” tire that was actually manufactured two years ago. It’s been sitting in a warehouse, aging quietly. Always check the DOT date before you buy, even if the salesperson swears it’s fresh stock.
How Old Is Too Old for RV Tires?
Most tire manufacturers and RV safety experts follow the 5-year inspection rule and the 7-year replacement rule. Here’s why:
The 5-Year Mark
At five years, start inspecting your tires closely for:
- Sidewall cracking
- UV damage
- Dry rot
- Loss of flexibility
The 7-Year Limit
By seven years, the rubber compound has degraded significantly, even if you’ve barely used the trailer. This is especially true for trailers that sit parked in the sun for months at a time. Whether you’re towing an 18 ft camper weight or a 24 ft camper weight, the age rule applies equally.
Why RV tires age faster than car tires:
- Higher weight loads – The average travel trailer weights put constant stress on sidewalls, even when parked.
- Static positioning – Long-term parking creates flat spots and UV exposure on one side.
- Higher PSI – Trailer tires run at 50–80 PSI, accelerating internal stress and heat cycles.
Why DOT Date Matters More Than Tread on RV Tires
This is the part most RV owners get wrong. You look at your tires, see plenty of tread left, and think, “These are fine for another season.”
Wrong.
Rubber degrades from the inside out. UV rays, ozone, temperature swings, and chemical breakdown all attack the molecular structure of the tire, long before the tread wears down. You can have 10/32″ of tread and still experience a catastrophic blowout on the highway because the sidewall is brittle.
The Real Danger: Sidewall Blowouts
When a travel trailer tire fails, it’s almost never from worn tread. It’s a sidewall blowout caused by:
- Cracked, aged rubber
- Internal heat buildup
- Overloading (especially common with the 30 ft camper weight and 30 ft rv weight categories)
A blowout at 65 mph can total your trailer, damage your tow vehicle, and put other drivers at risk. That’s why DOT date checks should be part of your pre-trip ritual, right alongside checking tire pressure and hitch security.
DOT Date Safety Checklist
Before your next trip, run through this quick checklist:
✅ Are any tires older than 5 years? If yes, inspect them carefully.
✅ Are any tires 7+ years old? Replace them, regardless of tread depth.
✅ Do you camp in high-heat states (Arizona, Nevada, Texas)? Age tires faster, knock a year off the safe lifespan.
✅ Are you towing heavy? If your trailer is near its GVWR, don’t take risks with old rubber.
✅ Planning a long-distance trip? Fresh tires = peace of mind.
Common Mistakes RV Owners Make
Mistake #1: Only Checking the Outside Sidewall
The complete DOT code is often on the inner sidewall. If you only check the outside, you might miss it entirely or get an incomplete code.
Mistake #2: Buying “New” Tires That Are Already Old
Some tire shops sell inventory that’s been sitting for 2–3 years. Always verify the DOT date before purchase. If they can’t show you a tire made within the last 12 months, walk away.
Mistake #3: Mixing Tire Ages on the Same Axle
Never run a 2-year-old tire next to a 6-year-old tire on the same axle. The difference in rubber integrity creates uneven handling and increases blowout risk.
Mistake #4: Ignoring Spare Tire Age
That spare mounted under your trailer? It’s aging too, possibly faster, since it’s constantly exposed to road grime and UV. Check its DOT date and replace it on the same schedule as your main tires.
DOT Date Rules for Travel Trailers vs Motorhomes
Travel trailers and motorhomes face different tire challenges:
Travel Trailers (ST tires)
Special Trailer (ST) tires are designed for towing, not driving. They have stiffer sidewalls to resist sway but also tend to age faster when parked. The average weight of camper loads on these tires can cause flat-spotting during long-term storage.
Motorhomes (LT or Commercial tires)
Motorhomes generate more heat because the tires are actively driven. However, they also get more regular movement, which helps prevent flat spots and keeps the rubber more flexible.
Bottom line: For travel trailers, static aging is the bigger enemy. For motorhomes, heat cycling and mileage are the main concerns.
DOT Date Considerations for Off-Road & BlackSeries Use
If you’re running an off-road travel trailer like the BlackSeries HQ series, DOT date becomes even more critical. Here’s why:
- Higher sidewall stress – Off-road trails put lateral forces on tires that pavement never does. Aged rubber can’t handle the flex.
- Low-speed ≠ low-risk – Crawling over rocks at 5 mph still generates heat and sidewall fatigue.
- Remote failure consequences – A blowout 40 miles into the backcountry isn’t just inconvenient, it can end your trip.
BlackSeries owners tend to push their rigs harder and farther than the average camper. That means tire maintenance isn’t optional, it’s survival. Even if your tires have low miles, if they’re approaching that 5-year mark and you’re planning a desert or mountain expedition, replace them.
FAQ – DOT Date on RV Tires
How do I read the DOT date on my RV tires?
Find the DOT code on the tire sidewall and look at the last four digits. The first two indicate the week, and the last two indicate the year of manufacture.
Are RV tires bad after 5 years even if unused?
Not necessarily “bad,” but they enter the inspection zone. By 7 years, replace them regardless of appearance or mileage.
Is the DOT code on both sides of the tire?
No, the full code is usually only on one side. You may need to check the inner sidewall to see the complete date.
Can I tow with 7-year-old RV tires?
It’s risky. Even with good tread, rubber deteriorates over time. Most experts recommend replacement at 7 years, especially for heavier loads like average travel trailer weights in the 24–30 ft range.
Should all trailer tires be the same DOT year?
Ideally, yes: especially on the same axle. Mismatched tire ages can lead to uneven handling and increased blowout risk.
Final word: Tread depth gets all the attention, but the DOT date is the real safety check. Whether you’re towing a lightweight 16 ft camper or a heavy-duty 30-foot rig, knowing when your tires were born: and when they need to retire: could save your trip, your trailer, and maybe even your life.
