In short. A valve stem is the small part in the wheel that lets air into a tubeless tyre and keeps it in. Most cars use one of three kinds: a rubber snap-in valve (TR413 or TR414), a metal clamp-in valve held by a nut, or a valve that carries the tyre pressure sensor (TPMS). Rubber valves are made for lower pressures and speeds than metal ones: the maker data we read give 4.5 bar (65 psi) and 210 km/h (130 mph) for rubber, 14 bar and 250 to 315 km/h for metal. Michelin and a sensor maker both say the valve, or on a sensor valve its seals, is replaced every time a tyre is changed. Keep the cap on: Michelin says a valve must always have one.
What a valve stem does
The valve is the only hole a tubeless tyre has, and it has two jobs. The body seals against the wheel's valve hole. The core, a small spring-loaded check valve screwed into the body, lets air in under pressure and closes when the pump comes off. The cap covers the core. Michelin puts the first job simply: "A tyre valve is a part of every tyre. It keeps the tyre sealed and prevents air from escaping" (Michelin UK).
Because it is a seal, the valve is one of the places a tyre can lose air without a puncture. The slow puncture guide lists the others and how to find which one leaks.
The three types
| Type | How it is held | Body | Limits in the maker data we read |
|---|---|---|---|
| Rubber snap-in, TR413 (ETRTO V2.03.1) | Pulled through the hole; the rubber grips the rim | Rubber over a brass stem, 42.5 mm tall | 4.5 bar (65.3 psi), 210 km/h (130.5 mph) |
| Rubber snap-in, TR414 (ETRTO V2.03.2) | Same, longer | Rubber over a brass stem, 48.5 mm tall | 4.5 bar (65.3 psi), 210 km/h (130.5 mph) |
| Metal clamp-in, aluminium (43LMS) | Nut on the outside, seal on the inside | Anodised aluminium | 14 bar (203.1 psi), 250 km/h (155.3 mph); nut 3 to 5 N·m |
| Metal clamp-in, brass (TR416S, ETRTO V2.05.1) | Nut and seal | Nickel-plated brass | 14 bar, 250 km/h |
| Metal clamp-in, brass (article 9-512512) | Nut and seal | Nickel-plated brass | 14 bar, 315 km/h (195.7 mph) |
Sources: technical data on the Wegmann automotive shop, Perfect Equipment brand for the TR413, TR414, Alligator brand for the 43LMS, TR416S and 9-512512. The conversions are ours: 1 bar = 14.5038 psi, 1 mph = 1.609344 km/h.
The names come from two catalogues, printed side by side on each product sheet: TR413 and TR414 under "Norm TR", V2.03.1 and V2.03.2 under ETRTO, the European tyre and rim technical organisation. We could not read the standards themselves, which are sold, not published; the dimensions above are the ones on the product sheets.
The hole. Both rubber valves fit a valve hole of 11.3 mm with a tolerance of +0.4 mm, so 11.3 to 11.7 mm, or 0.445 to 0.461 inch (our conversion). The 43LMS clamp-in valve is made for the same hole. A hole of another size needs a valve made for it.
Why the speed limit matters. 210 km/h is the top speed of the H speed symbol, and many tyres are rated above it: V is 240 km/h, W 270 km/h (see how to read a tyre size). The pages we read do not explain how the limit was set; they state it: the TR413 and TR414 sheets say "Only use for speeds up to 210 km/h", and BH SENS, a TPMS sensor maker, gives "210 km/h / 130 mph and maximum pressure is 4,5 Bar/ 65 psi" for its sensors on a rubber valve (user manual, December 2025). In the data we read, only the metal valves are rated above it.
Which one your car has. Look at the valve from outside. A black rubber body with a plastic cap is a snap-in valve. A metal body with a hexagonal nut against the face of the wheel is a clamp-in valve, and on a car with direct TPMS it often carries the sensor inside the tyre. A rubber valve can carry a sensor too: BH SENS sells its sensors with either, the rubber one bolted to the sensor with a Torx screw.
TPMS valves: what is different
A direct TPMS measures pressure with a sensor inside each tyre, and on most cars the sensor is fixed to the valve. That changes three things.
The nut has a torque, and it is small. A clamp-in sensor valve is held by a nut tightened with a torque wrench that reads in newton metres or inch-pounds, not by feel. Here are the figures in the documents we read:
| Document | Fixing | Torque | In lbf·in (our conversion) |
|---|---|---|---|
| Tesla Model 3 service manual | Nut attaching the sensor to the wheel | 8 N·m, nut marked "Reuse" | 70.8 |
| Tesla Model S service manual | Valve retaining nut, Continental sensor | 8 N·m | 70.8 |
| Tesla Model S service manual | Valve retaining nut, Baolong sensor | 5 N·m | 44.3 |
| Infiniti recall 09V-393 (2009) | New transmitter nut | 7.7 N·m (the bulletin gives 68 in-lb) | 68.2 |
| BH SENS installation guide | Torque nut, metal valve | 4 N·m (35 in-lb) | 35.4 |
| BH SENS installation guide and user manual | Torx screw, rubber valve to sensor | 1.25 N·m (11 in-lb) | 11.1 |
| Alligator 43LMS clamp-in valve | Nut | 3 to 5 N·m | 26.6 to 44.3 |
Sources: Tesla Model 3, Tesla Model S, Infiniti recall, BH SENS guide, Alligator 43LMS. Conversion: 1 N·m = 8.8507 lbf·in.
From one document to the next the nut torque runs from 3 to 8 N·m, nearly a factor of three, and the same car maker uses two figures depending on who made the sensor. So there is no general figure: the right one is in the service manual for the car or the sensor maker's sheet. These values are a few per cent of a wheel nut's; for those, see wheel nut torque.
Some nuts are made to give way. Tesla's Model S manual warns that "Before the full torque is reached, an internal break off ring will 'give'", and to keep tightening to the full figure. BH SENS describes the same feel: around 3 N·m "a sluggish movement until the shear collar breaks free", then on to 4 N·m in one continuous movement. A fitter who stops at the first resistance has not finished.
Metal and salt. A metal nut, stem and cap sit in road spray. Infiniti recalled the transmitter nuts of its 2008 to 2010 M35 and M45 in the US because the nuts, "not manufactured to specification", "may corrode and potentially crack, especially in areas where heavy concentrations of road salt are used", and replaced them at 7.7 N·m (NHTSA 09V-393, 5 November 2009). Hyundai ran a service campaign on the 2017 Tucson Night edition because "The aluminum valve cap may corrode onto the valve stem making it difficult to remove the cap to inflate tires or check tire pressure" (campaign 954, 7 May 2019). A metal cap is not a free upgrade.
The sensor's battery, the warning light and how to reset it are in TPMS light flashing or solid.
When to replace a valve stem
The sources agree on the tyre change and differ on the detail.
| Source | What it says |
|---|---|
| Michelin UK | "The valve replacement operation is always carried out when you fit a new tyre"; the rubber "loses its sealing properties" as it ages; on a sensor valve "the entire valve is not replaced, but only the seal inside" |
| BH SENS (sensor maker) | "The valve must be replaced every time the tire is changed", for both its metal and its rubber valves |
| Tesla Model 3 service manual | Sensor nut marked "Reuse" |
| Infiniti and Hyundai campaigns | Nut, cap or stem replaced when corroded |
Sources: Michelin UK, BH SENS, Tesla, Infiniti, Hyundai.
Read together: a rubber snap-in valve is replaced with the tyre, because the tyre has to come off to change it and the rubber ages. A sensor valve is a different case, since the sensor is the expensive part and is kept; Michelin says only the seal is changed, the sensor maker says the valve, and Tesla's manual lets the nut be reused. Where they differ, the car maker's and the sensor maker's documents for your car decide.
Between tyre changes, replace a valve when:
- it leaks. Michelin's test: with the cap screwed on, move the valve back and forth; "If you hear little noises of air escaping, it is porous". Soapy water on the valve shows a leak as small bubbles. The Infiniti bulletin asks for a wait of at least five minutes before looking.
- the rubber is cracked or perished, or the valve leans or is cut. In Great Britain the MOT treats a seriously damaged or misaligned valve as dangerous (below).
- a metal nut, stem or cap is corroded, as in the two campaigns above.
- the valve cannot be used: a core that will not hold, a cap seized on, a stem you cannot reach with a gauge.
Changing a valve means taking the tyre off the wheel, or at least breaking the bead. Tesla's manual warns that removing the core deflates the tyre fast and asks for safety glasses and gloves; Michelin recommends a professional, "Without this knowledge and equipment, replacing a valve can be risky". A sensor must not be struck by the tyre machine: BH SENS asks for the valve between 90 and 270 degrees from the bead breaker. If a valve is leaking fast, or the stem is cracked at the base, do not drive on it: fit the spare or have it checked before you take the road again.
Valve caps
The cap is not decoration. Michelin says "A valve must always have a cap to prevent air loss" (Michelin UK). The core does the sealing and the cap covers it. None of the texts in the next section lists a missing cap as a defect, which is no reason to drive without one.
The material matters: the Hyundai campaign above is about an aluminium cap that corroded onto the stem. The cap that came with the valve is the reference.
What the rules check, country by country
| Where | Text | What it says about valves and TPMS |
|---|---|---|
| Great Britain | MOT inspection manual, 5.2.3 | Defect (j): "A tyre valve seriously damaged or misaligned likely to cause sudden deflation of the tyre", dangerous. Defect (h): "Tyre pressure monitoring system malfunctioning or obviously not working", major, for M1 vehicles first used on or after 1 January 2012 |
| United States | FMVSS No. 138 (49 CFR 571.138) | Passenger cars and light vehicles up to 4,536 kg (10,000 lb) GVWR must warn "not more than 20 minutes after" a tyre falls 25 per cent below the maker's cold pressure (or a minimum set by the standard, whichever is higher), and warn of a malfunction; the owner's manual must tell you to check the malfunction light after replacing tyres or wheels |
| Canada | Transport Canada; Ontario inspection standard | Ontario's standard notes that "Tire Pressure Monitoring System (TPMS) is not a requirement in Canada"; it rejects a valve stem that is "cracked, damaged, leaking or inaccessible" or that prevents measuring, inflating or deflating the tyre. Transport Canada says to keep measuring pressure monthly and to make sure the sensors fit new rims |
| Queensland, Australia | Light Vehicle Inspection Manual, effective 7 July 2026 | A vehicle is rejected when "Valve stems are cracked, damaged, perished, or loose" |
Sources: MOT manual, FMVSS 138 (published 8 April 2005, amended 2005 and 2007), Transport Canada (modified 6 August 2021), Ontario standard, section 9, item 4, Queensland manual.
The MOT manual also explains how a tester reads the warning lamp: lit briefly at ignition then out is normal; staying on may only mean low pressure; flashing then steady can mean a fault. We did not find an Australian Design Rule that requires TPMS on cars, and other states' inspection manuals may word the valve item differently; check yours. Each state and province runs its own roadworthy inspection, so the Ontario and Queensland items are examples, not a national rule. How the MOT treats sensors on new wheels is in new wheels and the MOT.
Valves on a forged or aftermarket wheel
On a made-to-order wheel the valve is part of the design, not an afterthought. Three things have to agree:
- The hole. Its diameter decides which valves fit; the rubber valves and the 43LMS above are made for 11.3 to 11.7 mm.
- The type. The valve's speed rating has to cover the car's: in the data above, rubber valves stop at 210 km/h and only metal ones go beyond.
- The sensor. The sensor body sits inside the rim, against the drop centre. BH SENS says that once its rubber-valve version is mounted "the sensor must not touch the rim at any point", and Transport Canada says to make sure the pressure sensors fit the new rims. FMVSS 138 names wheels that stop the TPMS working as a cause of a malfunction warning.
Onyx Forged does not recommend a size or an offset, and it does not choose your valve or your sensor either: the car maker's documents and the sensor's fitting sheet do. If your car has TPMS, say so when you describe it to us, and ask customer service which valve the wheel takes before it is fitted, not after. Our wheels are designed to JWL/VIA standards. For the pressure itself, which is the car maker's, see tyre pressure.
Frequently asked questions
What are the types of tyre valve stem?
Three on most cars: a rubber snap-in valve (TR413 or the longer TR414), a metal clamp-in valve held by a nut, and a valve that carries the TPMS sensor, which can be either. Rubber ones in the maker data we read are limited to 4.5 bar and 210 km/h, metal ones to 14 bar and 250 to 315 km/h.
Should valve stems be replaced with new tyres?
Michelin says the valve is always replaced when a new tyre is fitted, because its rubber ages and loses its seal. On a sensor valve Michelin changes the seal, and the sensor maker BH SENS says the valve. Follow the car or sensor maker's document when they differ.
How tight should a TPMS valve nut be?
The figure in the car's service manual or the sensor maker's sheet. The documents we read give 4, 5, 7.7 and 8 N·m (35 to 71 lbf·in) for different sensors, so no single figure applies. Infiniti's bulletin asks for a small torque wrench; a figure this low cannot be judged by feel.
Can I drive with a leaking valve?
Not far. A slow leak should be found and fixed soon; a valve that is cracked, cut or loose can let the tyre down suddenly, and the MOT classes a seriously damaged valve as dangerous. Fit the spare or have it checked before you take the road again.
Do valve caps matter?
Yes. Michelin says a valve must always have a cap to prevent air loss. The cap covers the core. Mind the material: Hyundai had to replace aluminium caps that had corroded onto TPMS valve stems.
Are metal valve stems better than rubber?
For speed and pressure, yes, in the data we read: 250 to 315 km/h against 210 km/h. Metal ones need a torque on the nut, and their nuts can corrode in road salt, as an Infiniti recall showed. The car maker's original type is the safe reference.
Is TPMS required in my country?
In the US, on new light vehicles under FMVSS 138. In Great Britain the MOT tests it on cars first used from 1 January 2012. Ontario's inspection standard says TPMS is not a requirement in Canada, and we found no Australian Design Rule requiring it.
Why is my TPMS light on after a valve change?
A sensor may have been damaged, fitted the wrong way, or not relearned; the warning can also be plain low pressure. Our TPMS light guide explains the flashing and steady lights and the reset.
Where to go next
For a tyre that keeps losing air, start with the slow puncture guide; for the pressure to set once the valve is sound, tyre pressure. Onyx Forged is a French brand of made-to-order forged wheels: you can design a set with the valve and sensor of your car in mind.
Sources
- GOV.UK, MOT inspection manual for private passenger and light commercial vehicles, section 5.2.3.
- 49 CFR 571.138, FMVSS No. 138, tire pressure monitoring systems, Legal Information Institute.
- Transport Canada, tire pressure monitors; Ontario, Passenger / Light-Duty Vehicle Inspection Standard, section 9.
- Queensland Light Vehicle Inspection Manual, effective 7 July 2026.
- Michelin UK, tyre valve replacement (updated 8 September 2026).
- BH SENS: a simple guide to TPMS service (May 2022) and IntelliSens ECS and ECR user manual (December 2025).
- Tesla service manuals: Model 3, sensor TPMS; Model S, wheel sensor TPMS.
- Infiniti, safety recall R0909, NHTSA 09V-393 (5 November 2009); Hyundai, service campaign 954 (7 May 2019).
- Valve technical data, Wegmann automotive shop: Perfect Equipment TR413, TR414; Alligator 43LMS, TR416S, 9-512512.
All pages were read on 16 October 2026.
The Onyx Forged design office.