Stop Guessing Your Tire Cover Size
Confused about RV tire cover sizing? You’re not alone — and yes, getting it wrong can leave your tires exposed to harsh weather conditions and your wallet lighter.
We know you've seen it...
That guy who lives across from your place and keeps his RV parked in his side yard, with exposed, faded, flat tires sitting on damp grass, dry rotting their life away.
Not a pretty sight, right?
Well, this guide walks you through how to measure for RV tire covers the right way, step by step — even if the tire code is faded or missing.
This way you can install them properly, and keep your tires protected the way they should be.
Clear instructions. Common mistakes to avoid. For a great fit, every time.
Why Proper Measurement Is Crucial for RV Tire Covers
So first off, RV tire covers only work if they actually fit. Too loose, and they flap in the wind or fall off. Too tight, and they tear, crack, or won’t even fit around the tire.
Either way, improper cover sizes keep your tires exposed — and that’s a problem. And a big one!
Using the wrong size tire covers is a bit like wearing your little brother's T-shirt on a first date... Your gut's hanging out, everyone in the room can see your belly button, and it just isn't a good look if you're hoping for a second date, not for anybody.
But back to the tires... Sun, rain, wind, and road grime can break down unprotected tires faster than you’d think.
On the other hand, properly sized tire covers for RVs help prevent dry rot, UV damage, and premature wear — but that's only if the cover actually wraps around the full tire surface the way it’s designed to.
Here’s what accurate measuring your RV tires helps you avoid:
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Covers that sag or shift in bad weather
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Buying the wrong size (and wasting money returning it)
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Exposing parts of the sidewall to harsh conditions like sun and heat
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Struggling with installation because the fit is off
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Uneven wear from half-covered tires
No matter if you’re covering tires on a camper, motorhome, or travel trailer — the fit comes down to how well you’ve measured.
And it’s not just about protection... A snug, properly-fitted wheel cover for your RV also looks better. It makes your setup feel tight, dialed in, and cared for — which is exactly the vibe most RV owners are going for.
If you’ve ever seen a rig with lifeless camper wheel covers held on with bungee cords and ropes, just like that guy who lives across the street from your place, you know exactly what we mean.
How to Read the Sidewall of Your RV Tire
Dad always used to say: "If your truck don't start, check the battery before you rebuild the engine."
In other words, before you grab a tape measure, and start measuring your wheels by hand, check the sidewall of your tires.
In most cases, the size you need is already printed right there — if you know what to look for. Look for a string of numbers and letters, that'll look something like this:
225/75R15
Here’s what each part means:
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225 = Tire width in millimeters (from sidewall to sidewall)
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75 = Aspect ratio (the sidewall height is 75% of the width)
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R = Radial construction (standard on most modern RVs)
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15 = Wheel diameter in inches
The first number is really all you need to figure out the total height (diameter) of your tire — which is what matters most for choosing an RV tire cover that will fit properly.
If your tire code is clear, you can skip the manual measuring step below and jump straight to finding the perfect fitting RV tire cover size for your tires, using the calculator we’ve made available for you.
If the code is missing or too faded, no worries — we’ll walk you through how to measure it manually next.
Let's take a look!
How to Measure When You Can’t Find the Tire Code
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Measuring your tires isn't rocket science. But people still often get it wrong. Which is why any good man always measures twice, and cuts once.
Now, we're not cutting anything here. But the idea is the same.
And if the sidewall code on your RV tire is faded, dirty, or just plain missing — no worries. You can still get an accurate measurement using a simple, hands-on method.
You just got to keep a few simple things in mind. For example, before you start, make sure your tires are properly inflated. Flat or underinflated tires will throw off the numbers, and that could lead to the wrong cover size.
Tools You’ll Need:
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A tape measure (soft or flexible works best)
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A flashlight (if you’re working in a dim area)
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A notepad or your phone to record the numbers
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A second set of hands (optional but helpful for big tires)
Step-by-Step: How to Measure Tire Diameter and Width Manually
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Measure the height of the tire from the ground to the top of the tread - This is your overall diameter, and it’s the most important number when choosing a cover.
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Measure the width of the tire across the tread (side to side) - This gives you the tire’s full width, which helps ensure the cover wraps securely.
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Double-check for bulges or uneven surfaces - If the RV has been parked a while, the tires may have flattened slightly on the bottom. Roll the tire half a turn and remeasure.
- Write everything down - Even if you’re measuring all four tires, they may not all be exactly the same size — especially if there’s uneven wear. But this shouldn’t affect anything, unless you’re right between two tire cover sizes. Don't worry, though. Our calculator can help guide you.
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Measurements done? Nice work!
Now let’s make sure you get the exact RV tire cover size you need.
What Size RV Tire Covers Do I Need?
Whether you grabbed your numbers from the sidewall or measured directly, it’s now time to find the right product and get your perfect fit.
Use our RV Tire Diameter Calculator and plug in your numbers. The calculator instantly tells you the full diameter of your tire — no fancy equations or complicated manual math needed.
Launch the RV Tire Diameter Calculator Here
Once you have your full tire diameter, match it to the sizing chart below:
RV Tire Cover Sizing Chart
| Tire Diameter | Cover Size to Order |
| 23" – 25.75" | Small |
| 26" – 28.75" | Medium |
| 29" – 31.75" | Large |
| 32" – 34.75" | X-Large |
| 35" – 38.75" | XX-Large |
| 39" – 42" | XXX-Large |
Always choose the size that matches or slightly exceeds your tire’s full diameter. A snug but not overstretched is what will protect your tires best.
Ready to Protect Your Tires the Right Way?
Now that you know the tire cover size you need, it’s time to choose the right RV tire covers that actually do the job — week after week, and season after season.
At Tool Troopers, we designed the TIRESHIELD Pro Edition to handle everything the road and weather throw at you:
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Full UV protection, rain, snow, and dirt protection
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Reinforced fabric for long-lasting durability
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Rim-safe interior to prevent scuffs and scratches
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StormLock™ buckle system for a secure, storm-proof fit
Check out how it protects your tires — and your investment — below.
Find your perfect RV covers here
Do as any good road warrior or RVer would do, extend the life of your tires and don't leave them exposed — use tire covers that go the distance.
What About RVs with Dual or Tandem Axles?
The good news is that, if your RV, camper, or trailer has dual tires or tandem axles — the measuring process stays exactly the same.
So just as dad always famously quipped: "Don't fix what ain't broke!"
You still measure each tire individually from the ground to the top of the tread. But there are no complicated adjustments to the process.
What does change, however, is how you protect those tires once you know the right size.
Dual Tires: Two Covers Are Better Than One
If you have dual tires — meaning two tires mounted side-by-side on the same axle — you’ll want to cover each tire individually.
Stretching one big cover over dual tires might work for that guy across the street, but it often leads to a loose fit, sagging material, and faster wear — especially during windy conditions.
Covering each tire individually gives:
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A tighter, more secure fit
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Less chance of sagging or pooling
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Stronger protection for both sidewalls
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Easier installation and removal
So you simply measure one tire and order two covers — one for each.
Tandem Axles: Full Protection or Smart Short-Term Choices
If your RV has tandem axles — one set of wheels in front of another — you only need to measure one tire. Both tires are typically identical in size.
Just double-check for:
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Sizes that match
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Brands and models match
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Proper inflation and even wear
Similar to dual tires, for full protection, most road warrior agree that it's best to cover both tires individually.
Either way, one measurement is all you need to pick the right cover size for both.
What to Do If You Have Custom Rims or Tire Mods?
If your RV has aftermarket rims, oversized tires, or other modifications, don't trust the sidewall code alone.
Even small changes can affect the true diameter you need for a proper-fitting cover.
Here’s how to handle it:
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Measure directly across the tread and from ground to top.
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Ignore rim size alone — focus on full tire size.
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Account for wider tread or decorative wheel covers.
Pro Tip: Always measure twice when custom setups are involved. Better safe than sorry. You don't want to end up buying covers that don’t fit.
Common Mistakes to Avoid When Measuring for RV Tire Covers
Measuring isn’t complicated — but small mistakes can cause big headaches.
Here’s what to watch out for:
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Not finding the tire code - Always check the sidewall before grabbing a tape measure. As dad always said, keep it simple, stupid!
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Ignoring tire pressure - Flat tires throw off the size. Always inflate before you measure.
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Overlooking wheel diameter - Don’t just measure width — the full height matters most when shopping for a product that fits right.
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Measuring just one dual tire - Duals should be measured individually. They should be the same. But don’t assume they match.
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Rounding too much - Stick to whole numbers. If you’re between sizes, it’s safer to size up — not guess.
Just remember that taking an extra two minutes now, to measure and choose properly fitted covers, protects your tires for many years ahead.
You can thank us later!
Final Thoughts: Getting the Right Fit for Your RV Tires
Taking a few minutes to measure your RV tires the right way saves you from frustration, wasted money, exposed tires down the road.
It can also help you prevent RV tire blowouts and unnecessary damage to your RV.
Whether you read the sidewall code, measured manually, or accounted for custom mods... Great! You’re now ready to pick the perfect fitting tire covers.
Better protection. Longer tire life. And a rig that’s ready for whatever the road (or the weather) throws at it.
Not sure which size you need?
Use our RV Tire Diameter Calculator to double-check your numbers — and grab covers that fit like they were designed for your wheels.
Your RV deserves real protection!
Now you’ve done the hard part. Now let’s get those tires covered right.