RV Tire Pressure Guide: Why 80 PSI Matters for Safety

Sixty percent of RV blowouts are caused by tire underinflation. Not road hazards. Not defective rubber. Underinflated tires. That number comes from the National Highway Traffic Safety Administration, and after eight years living in a rig full-time, I believe every digit of it because I’ve watched it play out in campground after campground: someone rolls in on tires that look fine, and three days later they’re waiting on a roadside assist truck fifty miles from the nearest tire shop.

Most tire pressure guides for RVs start with “check your owner’s manual” and then give you a generic PSI chart that’s useless without context. So let’s skip that and talk about what actually matters.

The Number on the Sidewall Is Not Your Target

I made this mistake myself the first year I was on the road. My Class A had a sidewall that said 110 PSI max, so I ran 110 PSI. Felt solid. Sounded confident when I knocked on the tires. I was wrong.

The sidewall number is the maximum pressure the tire can hold at maximum load. Your job is to match pressure to your actual load, which requires a load-inflation table from the tire manufacturer, not the molded number. Michelin, Goodyear, and Continental all publish these tables for free on their websites. You find your tire’s load range, look up your axle weight (which you only know if you’ve actually weighed your rig, which most people haven’t), and set pressure accordingly.

The actual target pressure for most Class A motorhomes on the front steer axle runs 95-110 PSI, and rear axles often land between 80-100 PSI depending on load. Class C and Class B rigs, running on truck or van platforms, typically target 55-80 PSI on rear duals. But those are ranges. Your number depends on your weight.

If you haven’t weighed your rig at a CAT scale yet, do it before you read the rest of this. It’s $13.50 per pull as of August 2026, and it’s the single piece of data that makes everything else meaningful. Many RVers discover they’re running 500-1,200 lbs over their axle rating after that first weigh-in. That’s a conversation that deserves its own article, but tire pressure and axle weight are inseparable topics.

How Temperature Wrecks Your Setup

Here’s where people who set their pressure correctly in July get into trouble in October: tire pressure changes approximately 1 PSI for every 10°F change in ambient temperature. That’s not a rough guess, it’s basic gas law, and Michelin’s own tire care guide corroborates it.

If you inflated to 100 PSI on an 85°F afternoon in Phoenix and you’re driving a mountain road in the morning when it’s 45°F, you’ve already lost roughly 4 PSI before you leave camp. That doesn’t sound like much until you’re running duals and the inner tire at 96 PSI is taking load distribution hits it wasn’t designed for.

Check pressure cold. That means before the rig has moved, ideally in the early morning before the sun has been on the tires. Give the tires 30 minutes after parking if you just pulled in. Pressure checks taken after driving give falsely high readings because the air inside has expanded from heat generated by rolling friction. I’ve seen people add air based on a hot reading and then wonder why their tires look overinflated the next morning. That’s why.

Pressure by RV Class: Real Numbers

This table won’t replace your load-inflation table, but it’s a realistic starting-point guide based on manufacturer documentation and common configurations. Use it to sanity-check your numbers, not to set-and-forget.

One thing that trips people up: ST (Special Trailer) tires and LT (Light Truck) tires are not interchangeable in their pressure specs, even when the size looks similar. ST tires have stiffer sidewalls and often require pressures 5-10 PSI higher than their LT counterparts at the same load. Running an ST tire at LT-equivalent pressure is a common cause of trailer sidewall failures.

TPMS: Worth It or Gimmick?

Worth it. Not a gimmick. That’s my position, and it’s based on more than preference.

A 2023 RV Safety & Education Foundation report found that tire-related incidents account for over 30% of all RV roadside emergencies. A tire pressure monitoring system gives you real-time readings for every tire while you’re rolling, with alerts when pressure drops below a threshold you set. The slow leak that costs you $400 in roadside service plus a ruined rim becomes a 10-minute rest stop swap.

Entry-level TPMS units for RVs run $80-150 (the TireMinder A1A is a decent sub-$130 option for rigs with up to 10 tires). Mid-range systems with flow-through sensors that make inflation easier run $180-280. I’ve been running a TireMinder system for four years and it’s earned its keep twice on my current rig, once catching a valve stem leak on the rear driver’s side at 65 mph on I-40, and once alerting me to a bead leak on a freshly mounted tire a previous shop hadn’t seated properly.

The one practical thing nobody mentions: flow-through sensors let you add air without removing the sensor. If you have dual rear tires and you’ve tried to check and inflate the inner dual with a standard extension hose in a busy truck stop, you know why this matters. It’s genuinely awkward to the point of people skipping the check entirely.

A good TPMS system for RVs paired with a quality digital tire inflator are two purchases that actually improve day-to-day life on the road. (Disclosure: the site may earn a commission on those links.)

The Dual Tire Problem Nobody Talks About Enough

Scenario: a reader named Marcus from Albuquerque emailed me last spring after a blowout on I-25. His Class A had dual rear tires. He checked pressure monthly. But he checked the outer tire only, saw 95 PSI, figured he was good. The inner tire was at 62 PSI. He’d never checked it because the extension hose was a pain, and the inner tire looked normal from a visual inspection because duals support each other cosmetically even when one is critically low.

The inner tire was carrying overload on every mile until it gave up.

This plays out thousands of times a year across the RV community. Dual tires need individual checks, every single time, with a proper extension hose. No exceptions. If it’s physically difficult to check the inner tire on your rig, that’s a problem worth solving with better equipment, not ignoring.

Worked examples:

• Marcus, I-25 southbound near Socorro: Outer dual reads 95 PSI, inner unchecked → inner tire at 62 PSI takes unequal load → sidewall failure at mile 247 → $1,847 in new tire, rim repair, and roadside service.
• My own rig, Flagstaff in October: inflated to correct PSI in Phoenix at 88°F → parked overnight at 7,000 ft elevation, morning temp 34°F → morning check showed 95 PSI where 100 PSI was target → added 5 PSI before departing, drove clean.
• 5th wheel trailer at a CAT scale, full water tanks and gear: expected axle weight 14,200 lbs, actual weight 15,650 lbs → recalculated to load-inflation table → raised ST tire pressure from 65 PSI to 72 PSI to match actual load → correct load distribution confirmed.

Sources

• National Highway Traffic Safety Administration: Tire safety data attributing ~60% of blowouts to underinflation, cited in NHTSA consumer tire safety resources.
• Michelin Truck Tire Service Manual: Load-inflation tables and temperature coefficient data (1 PSI per 10°F).
• RV Safety & Education Foundation (2023): RV roadside emergency cause analysis, tire-related incidents exceeding 30% of calls.
• Goodyear Commercial Tire Systems: Load-range and inflation guidelines for commercial-grade RV tires.
• CAT Scale Company: Current weigh-in pricing and axle-weight methodology for trucks and RVs.

Photo: Nataliya Vaitkevich via Pexels