If you're searching for a generic RV tire pressure chart, let me save you some time: stop looking. A safe, one-size-fits-all chart simply doesn't exist because the correct inflation pressure is tied directly to your RV's specific, loaded weight—not some universal number.
The only safe pressure is the one that matches your actual axle weight to the tire manufacturer's official load and inflation tables. Honestly, using anything else is just a dangerous gamble with your safety and your rig.
Why A Generic RV Tire Pressure Chart Is Dangerous
Let's get straight to the point: any "universal" RV tire pressure chart you find online is not only wrong, but it's also incredibly unsafe to use. It's a common misconception, but that number stamped on your tire's sidewall isn't a recommendation. It's the maximum cold pressure the tire needs to support its maximum possible load—a weight your RV might never actually hit.
Here’s what really matters: your RV's actual weight when it’s loaded up for a trip. I'm talking fuel, water, all your gear, and everyone on board. This "actual loaded weight" is the single most important factor because it dictates the precise inflation needed to maintain the tire's shape, keep a proper footprint on the road, and prevent a catastrophic blowout. A generic chart or the sidewall number completely ignores this critical piece of the puzzle.
The Myth of "Max PSI"
I see it all the time. RVers inflate their tires to the "Max PSI" on the sidewall, thinking more pressure equals more safety. This is a dangerous myth that can lead to some serious problems on the road. When you overinflate a tire, it bulges in the middle, creating a crowned surface that drastically reduces how much of your tire actually touches the road.
An overinflated tire has a smaller footprint. This means less rubber is gripping the asphalt, which tanks your traction, hurts your stopping power, and causes the tire to wear out unevenly right down the center of the tread.
The Correct Approach to Tire Safety
The only reliable way to set your tire pressure is to first weigh your fully loaded RV, axle by axle. Then, you take those real-world numbers and consult your specific tire manufacturer's load and inflation tables. It's a process, but it ensures your pressure perfectly matches the load your tires are carrying, giving you the best possible safety and performance.
Getting this right is a fundamental part of RV ownership, just as important as keeping up with other essential RV parts. In this guide, I'll walk you through the exact steps to ditch the myths and adopt the professional, data-driven method for inflating your tires.
Understanding The Core Tire Inflation Formula
Every RV tire pressure chart, no matter the manufacturer, is built on a simple but powerful principle. Once you grasp this core concept, you'll see beyond just the numbers on a chart and understand why hitting the right inflation is so critical. This isn't just about ride comfort; it's about the basic physics of how your tires support your rig.
The entire system comes down to the direct link between the air pressure inside a tire and the weight it can safely carry. You have to stop thinking of the air in your tire as just filler. It's a structural component, giving the tire the strength to hold up thousands of pounds.
The Math Behind The Load
At its heart, the science is simple: the load a tire can handle is a direct result of its internal air pressure. When you let air out, you're literally removing the support structure, which kills its load-carrying capacity. And this isn't a small thing—even a minor drop in PSI can have a huge impact on safety.
For example, the tire industry demonstrates this relationship clearly. A standard 10-ply trailer tire inflated to 80 PSI might be rated to carry 3,085 pounds. If you let that pressure drop to 60 PSI—a 25% decrease—its capacity plummets to just 2,314 pounds. That's a 25% reduction in its ability to do its job. For more on this, YourNextTire.com has some great insights.
This proves there’s no "safety margin" when you run underinflated. You are simply overloading the tire for its current pressure.
From Formula To Real-World Application
So, what does this all mean for your RV sitting in the driveway? It means that before you even glance at a tire pressure chart, you have to know your actual, real-world weight.
By weighing your RV, you determine the actual load each tire must carry. The manufacturer's chart then tells you the correct tire pressure needed to safely support that specific load.
Following this process ensures you aren't just guessing or defaulting to the max PSI stamped on the sidewall. Instead, you're using real data to match the tire's capability to the actual demand you're placing on it.
- Step 1: Get Weighed. You must weigh your fully loaded RV to get an accurate load number for each axle. No shortcuts here.
- Step 2: Check the Chart. With that weight in hand, you can now look up the manufacturer's specified minimum cold inflation pressure.
This two-step process is the only way to correctly apply that core inflation formula. It takes a complex engineering principle and turns it into a simple, practical safety check you can—and should—do before every single trip. When you understand this, you're no longer just blindly following a chart; you're actively applying the science of tire safety.
How To Read Manufacturer Load And Inflation Tables
If there's one single source of truth for your RV's tire pressure, it's the manufacturer's load and inflation table. At first glance, they can look like a confusing spreadsheet full of numbers. But once you know what you're looking at, these charts are actually simple, powerful tools that give you the exact inflation numbers you need.
Learning to use one is probably the most important skill you can develop for tire safety. These tables, often called an RV tire pressure chart, are created by the engineers who designed and tested every part of your tire. They directly connect the weight a tire is carrying to the minimum cold PSI required to support that load without issue. All you have to do is bring one critical piece of information to the table: your RV's actual, weighed axle weight.
Decoding The Chart Terminology
Before you can pinpoint your exact pressure, you need to speak the chart's language. The terms are pretty standard across major brands like Michelin and Goodyear, so once you learn them, you can read almost any chart.
- Tire Size: The first step is to find the section of the chart that matches your specific tire size (e.g., 275/80R22.5). Everything else flows from there.
- Load Range: This is a letter (like G, H, or J) that tells you about the tire's construction and its maximum load-carrying ability. On the chart, your tire size will be grouped under its specific load range.
- Single vs. Dual: This is absolutely critical. A "Single" setup is an axle with one tire on each side, like your front steer axle. A "Dual" or "Dually" setup has two tires side-by-side on each end of the axle, common for the rear of many larger motorhomes. The load capacity and required PSI are very different for each.
A Step-By-Step Example
Let's walk through a real-world scenario. Say you have a Class A motorhome with a single front axle and a dual rear axle. You’ve done the most important thing—you took your fully loaded rig to a scale and got your actual weights. Here’s what you found:
- Your front axle weighs 9,500 lbs. This load is split between two tires, so each front tire is carrying about 4,750 lbs (9,500 ÷ 2).
- Your rear axle weighs 18,000 lbs. In a dually setup, this weight is supported by four tires.
Now, grab the manufacturer's chart. First, find your tire size, then look at the "Single" column for your front axle. Scan down the weight column until you find the number that is equal to or just above your measured load of 4,750 lbs. The PSI listed in that same row is your minimum cold inflation pressure. You'll set both front tires to that pressure.
Next, shift your focus to the "Dual" column for your rear tires. Scan down until you find the weight that corresponds to your 18,000 lbs rear axle load. The chart will show the required PSI for each of the four rear tires to safely handle that combined weight.
The core principle here is to weigh each axle end and use the heavier side's weight to set the pressure for all tires on that axle. This removes all the guesswork. You can learn more about this professional weighing method and explore Michelin's detailed load tables to see more examples.
To make this even clearer, here's what a small section of a manufacturer's chart might look like for a common tire.
Sample Manufacturer Load & Inflation Table (Single Wheel)
This table demonstrates how to find the required PSI for a common RV tire size based on the measured weight on a single-wheel axle end.
| Inflation Pressure (PSI) | Load Capacity per Tire (Lbs) | Load Capacity per Axle (Lbs) |
|---|---|---|
| 80 | 4,370 | 8,740 |
| 85 | 4,550 | 9,100 |
| 90 | 4,750 | 9,500 |
| 95 | 4,920 | 9,840 |
| 100 | 5,100 | 10,200 |
In our example, with a front axle load of 9,500 lbs (or 4,750 lbs per tire), you would find the 4,750 lbs row and see that the required minimum cold inflation pressure is 90 PSI. It’s that simple.
By matching your real-world weight to the manufacturer's data, you're ensuring your tires have the precise pressure they need. This isn't just about tire life; it's about optimal safety, better handling, and peace of mind on every single trip.
Your Step-By-Step Guide To Weighing Your RV
Before you can even think about using an RV tire pressure chart, you need real-world weight data. I’m not talking about the sticker weight from the manufacturer—that’s for an empty rig. You have to weigh your RV exactly how you travel: with full tanks of fuel and fresh water, propane, all your gear, food, and every person and pet on board. Guessing is a surefire way to get your tire pressures dangerously wrong.
The absolute best way to do this is called four-corner weighing. This method measures the weight on each individual wheel, which is a game-changer. It shows you imbalances from one side to the other, something that’s incredibly common with heavy slide-outs, refrigerators, or even just how you pack your storage bays. Getting these specific weights is the only way to dial in the safest possible tire pressure.
This guide shows how your tire size, the weight on the tire, and the final PSI all work together.
As you can see, those three pieces of information are directly linked. Get one wrong, and the whole calculation falls apart.
How to Weigh Your RV at a CAT Scale
Certified Automated Truck (CAT) scales, found at most truck stops, are your most convenient option for getting accurate axle weights. While they aren't set up for a true four-corner weigh, you can still get the crucial data you need to make smart, safe decisions about your tire pressure.
Here’s the process to follow:
- Find a Scale: Use an app like Weigh My Truck to find a CAT scale on your route, or a quick Google search works just as well.
- First Weigh (Total Weight): Pull your entire rig onto the scale pads. These are usually split into three sections. Ensure your front axle is on the first pad, your drive axle is on the second, and your toad or trailer axles are on the third. Follow the instructions over the speaker, and you’ll get your first weight ticket with individual axle weights.
- Calculate and Confirm: The first ticket breaks down the weight on each pad, which lines up with your steer (front) and drive (rear) axles. This gives you the axle weight you need for the load charts. Some RVers do a second weigh for more data, but the first is essential.
A critical reminder: Don't show up with an empty rig. It must be loaded for a trip—people, pets, water, and all your gear. An empty weight is totally useless for setting tire pressure.
The Four-Corner Method
For the most accurate numbers possible, nothing beats a dedicated four-corner weigh. Organizations like the RV Safety & Education Foundation (RVSEF) are a great resource for this, often offering the service at RV rallies and events. They use portable scales under each wheel, giving you the exact load every single tire is shouldering.
This method almost always uncovers surprising side-to-side weight differences. It’s not uncommon to find that the driver's side of an axle is 500 pounds heavier than the passenger's side. If you find an imbalance like this, you must use the heavier weight to set the PSI for both tires on that axle. Never average the weights or run different pressures on the same axle.
Taking the time to get your rig properly weighed is just as critical for safety as using the best RV leveling blocks for stability when you get to camp. It's the single most important step you can take to make sure your tires are correctly inflated for every single mile of your journey.
Special Inflation Rules For Trailer (ST) Tires
If you're pulling a travel trailer or fifth-wheel, you can't treat its tires like the ones on your motorhome. Towable RVs use a special breed of tire called a Special Trailer (ST) tire, and they play by a completely different set of rules when it comes to inflation.
These aren't just beefed-up car tires. They're engineered from the ground up with much stiffer sidewalls specifically to handle heavy vertical loads and minimize the dangerous trailer sway that can turn a relaxing drive into a white-knuckle affair.
Because of this unique, heavy-duty construction, ST tires are meant to run at significantly higher pressures than the passenger (P) or even Light Truck (LT) tires on your tow vehicle. Their main job is to carry weight safely, not to provide a cushy ride or sharp steering response. This is a critical point—never, ever substitute a passenger tire on a trailer. It's an incredibly dangerous mistake that can lead to a fast and catastrophic failure.
The Power of High Pressure in ST Tires
The link between air pressure and how much weight a tire can carry is even more pronounced with ST tires. Their rigid design absolutely depends on high PSI to maintain shape and support the massive weight of a fully loaded rig.
Running them even a little bit low on air causes the sidewalls to flex excessively, which generates a ton of heat and can quickly lead to a blowout. A proper rv tire pressure chart for ST tires will always show a dramatic jump in load capacity as the pressure goes up.
To give you a real-world example, let's look at a common ST tire, the ST235/80R16. The industry's own load and inflation tables show just how much of a difference a few PSI can make.
ST Tire PSI vs Load Capacity Example (ST235/80R16)
This table shows how much more weight a common ST tire can safely carry as you increase the inflation pressure. Notice the massive jump in capacity from 65 to 80 PSI.
| PSI | Load Capacity per Tire (Lbs) |
|---|---|
| 65 | 1,720 |
| 70 | 1,930 |
| 75 | 2,270 |
| 80 | 2,600 |
At 65 PSI, this tire can support 1,720 pounds. Pump it up to 80 PSI, and its capacity skyrockets to 2,600 pounds—that's a 51% increase! It's a perfect illustration of why max pressure is so important. You can check out the full ST tire load inflation tables yourself to see this across different sizes.
Here's the key takeaway: Always inflate your ST tires to the maximum cold PSI listed on the tire's sidewall. Unlike motorhome tires where you adjust pressure for the load, ST tires are designed to perform best—and safest—only at their max rated pressure. This ensures they can handle their full weight capacity and keep sway under control.
Understanding Load Ranges for ST Tires
When you look at ST tire charts or the sidewall of the tire itself, you'll see letter designations like C, D, or E. These are called Load Ranges, and they're a quick way to know the tire's strength and maximum pressure rating.
- Load Range C: Typically rated for a maximum of 50 PSI.
- Load Range D: Generally rated for a maximum of 65 PSI.
- Load Range E: Often rated for a maximum of 80 PSI.
This system makes it easy to quickly identify a tire's capabilities. Your trailer's federal certification sticker (usually on the driver's side) or the owner's manual will tell you the exact tire size and load range your rig requires. The rule here is simple: always match that spec and inflate to the max PSI stamped on the tire. It’s the single best thing you can do for a safe and stable towing experience.
A Practical Guide To Checking And Adjusting Tire Pressure
You’ve done the hard part—you’ve weighed your rig and have the manufacturer's load and inflation tables right in front of you. Now for the most important step: getting out there and actually checking and adjusting your tires. This isn't just a suggestion; it's a non-negotiable part of your pre-trip safety inspection.
Getting this process right is what turns the numbers on your RV tire pressure chart into real-world safety on the highway. It’s all about consistency, having the right tools for the job, and knowing what your pressure readings are actually telling you.
Essential Tools For The Job
Before you even think about touching a valve stem, you need to have the right gear. Using cheap or improper tools will just lead to bad readings and a lot of frustration, completely defeating the purpose of this critical check.
- A High-Quality Digital Pressure Gauge: Forget those old pencil-style gauges. You need a reliable, dual-head digital gauge that can easily reach the valve stems on both your inner and outer dually tires and give you a precise, easy-to-read number.
- A Capable Air Compressor: RV tires, especially on bigger motorhomes, need a lot of pressure—often 100 PSI or more. Your standard car tire inflator isn't going to cut it. Invest in a portable air compressor designed for RVs that can comfortably hit your target pressures without struggling.
Having these tools ready to go makes the whole process quick and accurate. It means you can perform this check anywhere, whether you're in your driveway or at a remote campsite.
The Cold Inflation Rule Is Non-Negotiable
If you take away only one thing from this guide, let it be this: always, always check and adjust your tire pressure when the tires are cold. This has nothing to do with the weather; it means the tires are at the same temperature as the surrounding air.
A "cold" tire is one that hasn't been driven on for at least three to four hours and hasn't been sitting in direct, hot sunlight.
As you drive, your tires generate friction and heat. That heat causes the air inside to expand, which in turn increases the pressure. If you check your tires when they're hot, you'll get a falsely high reading. If you then let air out to match your chart's recommendation, your tire will become dangerously underinflated once it finally cools down. It's a classic and risky mistake.
Step-By-Step Pressure Check And Adjustment
Follow this workflow every single time you check your tires. Consistency is what keeps you safe.
- Secure Your RV: First, make sure your rig is parked on a level surface with the parking brake fully engaged. For extra safety, I always recommend chocking the wheels on the opposite side from where you're working. We have a great guide on the best RV wheel chocks if you need some recommendations.
- Remove Valve Caps: Go around and unscrew the valve stem caps from every tire. Stick them in your pocket so they don't roll away and get lost.
- Check Each Tire: Press your gauge firmly onto the valve stem until it gives you a solid, stable reading. Start with the front tires, then move to the rears, making sure to get both the inner and outer tires on a dual-wheel setup. Write down the pressure of each tire as you go.
- Compare To Your Chart: Take your cold readings and compare them to the pressure specified on the manufacturer’s load and inflation chart for your measured axle weight.
- Adjust As Needed: If a tire is low, grab your air compressor and add air in short bursts. Re-check the pressure frequently until you hit the target PSI. If a tire happens to be overinflated (perhaps from a significant drop in ambient temperature), use the little nub on your gauge to press the pin in the valve stem and release air slowly until it matches the pressure you need.
- Replace Valve Caps: Once all your tires are set perfectly, securely screw all the valve stem caps back on. They’re your first line of defense against dirt and moisture getting into the valve core and causing a leak.
The Role Of A Tire Pressure Monitoring System
If you ask me, a Tire Pressure Monitoring System (TPMS) is one of the single most important safety upgrades you can add to your RV. Think of it as your vigilant co-pilot, constantly keeping an eye on your tires so you can keep your eyes on the road. Now, this system isn’t a replacement for manual checks with a quality gauge, but it's an absolutely critical early-warning tool that gives you real-time data on the two biggest threats to your tires: pressure and temperature.
The real benefit of a TPMS is its ability to spot trouble long before you could ever feel it from the driver's seat. A slow leak or a tire that’s starting to overheat from a bad bearing won't give you any obvious clues until it’s dangerously close to a catastrophic blowout. A TPMS, on the other hand, will alert you the moment a tire’s pressure drops below your baseline or its temperature spikes.
Key Features To Look For In An RV TPMS
When you’re shopping for a system, you’ll quickly find they aren't all created equal. You need a setup specifically designed for the unique demands of an RV, which are a world apart from a standard passenger car. Here’s what I always recommend looking for:
- Real-Time Data: The system must provide live, continuous readouts for both pressure (PSI) and temperature for every single tire—that includes your tow vehicle and your trailer or toad.
- Customizable Alerts: You must be able to set your own custom high and low-pressure alarms. This is non-negotiable, as you'll be setting that low-pressure warning based on the minimum cold inflation pressure from your RV tire pressure chart.
- Strong Signal Range: Ensure the system either includes a signal booster or is powerful enough on its own to reliably send a signal from the tires on a 40-foot trailer all the way to the monitor in your truck cab. Dropped signals are useless signals.
- User-Replaceable Batteries: Get sensors with batteries you can easily swap out yourself. It'll save you the massive headache and expense of shipping them back to the manufacturer every couple of years.
Setting Up Your TPMS For Maximum Safety
Picking the right TPMS is only half the battle; setting it up correctly is just as important. The whole point is to create a digital safety net based on the correct cold inflation pressures you've already figured out. Never rely on some generic factory preset.
The most critical setting is your low-pressure alarm. A solid rule of thumb is to set this alert to trigger at 10% below your target cold inflation pressure. This gives you a heads-up on a slow leak without driving you crazy with false alarms from normal day-to-day temperature swings.
For instance, if your front steer tires call for 90 PSI when cold, you'd set that low-pressure alarm to sound off at 81 PSI. Following that same logic, the high-pressure warning is usually set 20-25% above your cold PSI. This is designed to catch an abnormal heat-related pressure spike that could point to a much bigger issue, like a dragging brake or failing bearing.
A TPMS is like an insurance policy. You hope you never have to use it, but if a tire does start to fail, that instant warning gives you the crucial minutes you need to pull over safely. It can be the difference between a simple tire change and a dangerous blowout that causes thousands in damage to your rig.
Common Questions About RV Tire Pressure
Working with RV tires brings up a lot of questions, especially for folks new to the lifestyle. In this final section, I’ll tackle some of the most common ones I hear from fellow RVers out on the road. The goal here is to give you clear, direct answers to build on what we've already covered.
Think of this as your go-to FAQ for everything related to your RV tire pressure chart. These are the practical, real-world details that can make all the difference.
Should I Inflate My RV Tires To The Max PSI On The Sidewall?
Almost never. You should only inflate your tires to the max PSI stamped on the sidewall if your weighed axle load requires it, according to the manufacturer's chart. That number is a safety limit, not a daily driving recommendation. It represents the pressure needed to support the tire's maximum possible load.
The only safe way to determine your pressure is by weighing your rig and matching that axle weight to the manufacturer’s load and inflation chart. Over-inflating to the max PSI can cause a handful of serious problems:
- A Bone-Jarring Ride: The tires become rock-hard, transferring every bump and pothole straight into your RV's frame and everything inside it.
- Reduced Grip: The tire bulges out in the middle, which shrinks the contact patch—the amount of rubber touching the pavement. Less grip is never a good thing.
- Uneven Tread Wear: With a smaller contact patch, the center of the tread wears out way faster than the edges, shortening the life of your expensive tires.
The right pressure is always determined by your actual, measured load. That "Max PSI" number is a ceiling, not a target. Stick to the manufacturer’s load chart for your specific weight.
How Much Does Tire Pressure Increase While Driving?
It's completely normal for tire pressure to go up as you drive. As your tires flex and roll down the highway, they create friction and heat, which causes the air inside to expand. You can expect to see a pressure increase of about 10-15% from their cold setting.
For instance, if you set a tire to 100 PSI cold in the morning, it could easily climb to 110-115 PSI on a hot afternoon of driving. Don't panic! Tire engineers fully expect this and design the tires to handle it. The single most important rule here is to never bleed air from a hot tire. If you let air out to get it back to the "cold" pressure, it will be dangerously underinflated once it cools down.
What Is The Difference Between Single And Dual Tire Configurations?
Getting this straight is crucial for reading any RV tire pressure chart correctly. The terms simply refer to how many tires are on each end of a single axle.
A single setup means you have one tire on each side of an axle, for a total of two tires. This is what you'll find on the front steer axle of every motorhome and on all axles of most travel trailers.
A dual (or "dually") setup means there are two tires mounted side-by-side on each end of the axle, for a total of four tires. You'll see this on the rear drive axles of bigger Class A and Class C motorhomes. Because the weight on that axle end is shared between two tires, the required inflation pressure is different—and usually lower—than what a single tire would need to carry that same load by itself.
At RVupgrades.com, we know that having the right parts is essential for a safe and enjoyable journey. From high-quality tire pressure monitoring systems to reliable air compressors and gauges, we stock over 20,000 products to help you maintain your rig with confidence. Find everything you need for your next adventure at https://www.rvupgradestore.com.
