First-Trailer Essentials & Tires
Travel Trailer Tire Pressure Guide
Car habits do not transfer. ST tires are specified at their maximum cold pressure, and running them soft is how they overheat.
By Mike M. ·
How this page is funded: we earn a commission if you buy through our links, at no extra cost to you. It never changes which product we rank first. Prices come from Amazon and are read automatically — each one shows the date it was read. Full disclosure.
Quick picks
The gauge and the monitor this guide depends on.
| # | Product | Best for | Score | Price |
|---|---|---|---|---|
| 1 |  Milton S-986 Dual Head Tire Pressure Gauge, 10-160 psi Trailer tires often run 50-80 psi, which is past the top of a typical car gauge. This one reads to 160 psi and the dual head reaches an inner dually valve. Must read above 60 psi | Reading trailer tire pressure that a car gauge cannot | 9.6/ 10 | |
| 2 |  TireMinder i10 RV TPMS with 4 Transmitters Four transmitters and a dedicated monitor, which is exactly the count a tandem-axle travel trailer needs. The dedicated screen beats a phone app you have to keep awake. | A straightforward four-tire TPMS for a tandem-axle trailer | 7.5/ 10 | |
| 3 |  Carlisle Radial Trail HD Trailer Tire, ST205/75R15, 107M A genuine special-trailer radial in the size most single- and tandem-axle travel trailers wear, with a load index and speed symbol printed on the sidewall you can actually check. | The most common travel trailer size, at a sensible price | 8.0/ 10 | |
| 4 |  RVMATE RV Tire Covers, 4-Pack, Fits 27-29 in Tires Trailer tires usually die of age and sun rather than tread wear, so covering them during storage is the cheapest life extension available. Four covers, one purchase. | Slowing the UV aging that kills trailer tires | 7.9/ 10 |
Tap any row to jump to the full write-up. Prices come from Amazon and are read automatically — see each product below for the date.
The short answer
This is the single most transferable-looking habit that does not transfer. On a car you run the pressure on the door sticker, which is below the tire’s maximum, because the car is tuned for ride and grip. A trailer is not tuned for anything — it is carrying weight.
Why the maximum
An ST tire’s rated load capacity is quoted at its maximum cold inflation pressure. Below that pressure it carries less, and the published tables are explicit about how much less.
A trailer tire also has very little margin. Four tires on a tandem axle carry most of the trailer’s weight, they have stiff sidewalls that need pressure to work as designed, and nobody is adjusting pressure for load the way a truck operator might. Running the maximum is the simple, conservative answer, and it is what the makers specify.
The other half of the reason is heat. An underinflated tire flexes more at the sidewall, flex generates heat, and heat is what destroys trailer tires. A tire 15 psi low on a hot interstate is building heat continuously for hours.
Cold pressure: measured before the trailer has been driven, or after at least three hours parked. Driving heats the air inside and raises the reading, so a “correct” hot reading means the tire was underinflated cold.
The placard and the sidewall
Two sources, and they usually agree.
The trailer placard — usually on the front left exterior wall — gives the tire size, load range and cold inflation pressure the trailer was built for.
The tire sidewall gives the maximum cold inflation pressure for that specific tire.
If they differ, the usual cause is that someone fitted a different load range from the original. In that case the correct pressure is the one appropriate to the tire now fitted for the load it is carrying — which is another reason to match the placard when replacing tires. The tire picks.
| Load range | Ply rating | Typical max cold pressure |
|---|---|---|
| B | 4 | 35 psi |
| C | 6 | 50 psi |
| D | 8 | 65 psi |
| E | 10 | 80 psi |
Measuring it properly
- 1
Measure cold
Before the trailer has moved, or after at least three hours parked. First thing in the morning is ideal and that is when most people are leaving anyway. - 2
Use a gauge that reads above 60 psi
Most car gauges top out around 50-60. A gauge that cannot read your pressure gives you a number and the number is wrong, which is worse than no number. - 3
Check all of them, including the spare
The spare is the one nobody checks and the one you need on the worst possible day. Check it when you check the others. - 4
Do not bleed down a hot tire
Pressure rises with heat and that is normal and expected. Letting air out of a hot tire leaves it underinflated when cold, which is the condition that caused the heat in the first place.
The common mistake
What temperature does to the reading
Roughly 1 psi per 10 degrees Fahrenheit of air temperature change, plus the heat the tire generates by running. Two practical consequences:
Seasonal. A trailer set to 65 psi in a 75-degree summer reads noticeably lower on a 35-degree spring morning. Check at the start of each trip, not once a season.
In use. Pressure rising as you drive is normal. A tire whose pressure rises much more than its neighbors is doing more work than they are, which is information a monitor gives you and a gauge does not. TPMS picks.
Three other things that matter as much
Age. Correct pressure does not save a tire that is past its date code. Trailer tires age out rather than wear out. The aging story.
UV. Sidewall degradation from sunlight is the actual failure mechanism, and covers during storage directly address it.
Speed. Heat build-up rises sharply with speed and the sidewall speed symbol is a limit rather than a target. Sixty is a good working number.
What to remember
- ST tires are specified at their maximum cold sidewall pressure, often 50-80 psi.
- Measure cold, before driving or after three hours parked.
- Use a gauge that reads above 60 psi. Most car gauges do not.
- Never bleed down a hot tire — the sidewall figure is a cold specification.
- Roughly 1 psi per 10 degrees F of ambient change, so check each trip.
The picks in full
Milton S-986 Dual Head Tire Pressure Gauge, 10-160 psi
Milton · Best for reading trailer tire pressure that a car gauge cannot
Trailer tires often run 50-80 psi, which is past the top of a typical car gauge. This one reads to 160 psi and the dual head reaches an inner dually valve.
Key specifications
- Range
- 10-160 psi
- Head
- Dual head chuck
- Type
- Straight foot, mechanical
- Model
- S-986
How it scored
- How often you use it (40%)10
- Build quality (25%)9
- Takes up little room (20%)9
- Price for capability (15%)10
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Range actually covers trailer tire pressures
- Dual head reaches awkward and inner valves
- Mechanical — no battery to die in a cold trailer
What it is bad at
- Analog scale is harder to read precisely than a digital gauge
- No calibration certificate
- Brass head is heavy in a pocket
Price as of October 5, 2026. #ad How this is funded
TireMinder i10 RV TPMS with 4 Transmitters
TireMinder · Best for a straightforward four-tire tpms for a tandem-axle trailer
Four transmitters and a dedicated monitor, which is exactly the count a tandem-axle travel trailer needs. The dedicated screen beats a phone app you have to keep awake.
Key specifications
- Transmitters
- 4 included
- Monitor
- Dedicated display
- Expandable
- Yes, additional transmitters
- Model
- i10
How it scored
- Sensor coverage (25%)7
- Display (25%)8
- Alerting (25%)8
- Battery life (15%)7
- Price for capability (10%)7
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Four sensors matches a tandem-axle trailer with no add-ons
- Dedicated monitor, not a phone app
- Established name in RV tire monitoring
What it is bad at
- Four sensors means no spare coverage without buying a fifth
- Monitor needs 12 V power routed to it
- Sensor batteries are a periodic chore
Price as of October 5, 2026. #ad How this is funded
Carlisle Radial Trail HD Trailer Tire, ST205/75R15, 107M
Carlisle · Best for the most common travel trailer size, at a sensible price
A genuine special-trailer radial in the size most single- and tandem-axle travel trailers wear, with a load index and speed symbol printed on the sidewall you can actually check.
Key specifications
- Size
- ST205/75R15
- Load index / speed
- 107M (about 2,149 lb per tire, 81 mph)
- Construction
- 8-ply rating radial
- Type
- ST — special trailer
Capacity figures read from FMVSS 109 — new pneumatic tires (load and marking requirements), October 2026.
How it scored
- Load rating (30%)8
- speed (20%)7
- Build quality (25%)8
- Size availability (15%)9
- Price for capability (10%)9
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Correct ST construction, with stiffer sidewalls than a passenger tire
- Widely stocked, so a roadside replacement is findable
- Load rating suits most 5,000-7,000 lb tandem-axle trailers
What it is bad at
- M speed symbol means 81 mph — not a license to tow at 80
- Trailer tires age out before they wear out; the date code matters more than the tread
- Sold individually, so a set is four purchases
Price as of October 5, 2026. #ad How this is funded
RVMATE RV Tire Covers, 4-Pack, Fits 27-29 in Tires
RVMATE · Best for slowing the uv aging that kills trailer tires
Trailer tires usually die of age and sun rather than tread wear, so covering them during storage is the cheapest life extension available. Four covers, one purchase.
Key specifications
- Pack
- 4 covers
- Fits
- 27-29 in diameter tires
- Material
- Waterproof fabric
- Use
- Storage and seasonal parking
How it scored
- How often you use it (40%)8
- Build quality (25%)7
- Takes up little room (20%)7
- Price for capability (15%)10
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Directly addresses UV, the usual cause of trailer tire failure
- Four covers for less than one tire costs
- Quick to fit and remove
What it is bad at
- Measure your tire diameter — 27-29 in does not fit every trailer
- Fabric covers can trap moisture if fitted wet
- They flap and wear in constant wind
Price as of October 5, 2026. #ad How this is funded
Common questions
The maximum cold pressure on the sidewall, unless the trailer placard says otherwise — commonly 50 psi for load range C, 65 for D, 80 for E. ST load capacity is quoted at maximum pressure.
No. Pressure rising with heat is normal. Bleeding down hot leaves the tire underinflated cold, which causes more flex and more heat.
Most car gauges top out around 50–60 psi and trailer tires run 65–80. Beyond its range a gauge gives a wrong reading, which is worse than none. Use one rated to at least 100 psi.
Cold, at the start of every trip and before each travel day on a longer one. Ambient temperature alone shifts pressure by roughly 1 psi per 10°F.
Sources
- FMVSS 109 — new pneumatic and certain specialty tires — read October 2026
- FMVSS 139 — new pneumatic radial tires for light vehicles — read October 2026
- Tire Industry Association — read October 2026