SL vs XL tires
SL means standard load. XL means extra load (also called reinforced): the tire has a stronger carcass than the standard tire of the same size. On an XL tire, the sidewall shows the words "EXTRA LOAD" or "REINFORCED".
| Passenger tire | Maximum pressure (psi) | TPMS minimum (psi) |
|---|---|---|
| SL, standard load | 35 / 44 / 51 | 20 |
| XL, extra load | 41 / 49 | 23 |
Maximum pressures and TPMS minimum activation pressures from FMVSS No. 138 Table 1. A tire with no XL marking is a standard load tire.
What is different
- An XL tire has a stronger structure, so it has a higher maximum pressure than the SL tire of the same size.
- The load index on the sidewall gives the maximum load for each tire. Compare the load index of the two tires, not the SL or XL letters. See the load index chart.
- For the tire pressure light, FMVSS No. 138 uses a minimum of 23 psi for XL tires and 20 psi for SL tires.
Which pressure to use
Use the cold pressure on the vehicle placard (FMVSS No. 110 S4.3), not the maximum on the sidewall. If you change from SL to XL tires, or from XL to SL, the correct pressure can change. Ask the tire maker or the vehicle maker for the pressure that gives the load you need.
SL and XL against load range
SL and XL are for passenger tires. Light-truck (LT) tires use load range letters such as C, D and E instead. See the load range chart and load range E tires.
Printed from https://tiresizecalc.net/sl-vs-xl-tires/. Figures as published on 2026-11-01. The sources are listed below.
Sources
- UN Regulation No. 30 - Uniform provisions concerning the approval of pneumatic tyres for motor vehicles and their trailers (Revision 3). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.29/Rev.3. 2007-03-29. Para 2.3.4: reinforced or extra load tyre definition. Retrieved 2026-11-01.
- UN Regulation No. 30 - Uniform provisions concerning the approval of pneumatic tyres for motor vehicles and their trailers (Revision 3). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.29/Rev.3. 2007-03-29. Para 3.1.8: the words REINFORCED or EXTRA LOAD on a reinforced tyre. Retrieved 2026-11-01.
- 49 CFR 571.138 - Standard No. 138; Tire pressure monitoring systems. National Highway Traffic Safety Administration (NHTSA), Code of Federal Regulations, annual edition (GovInfo). 2022-10-01. Table 1: P-metric standard load and extra load maximum pressures and minimum activation pressures. Retrieved 2026-11-01.
- 49 CFR 571.110 - Standard No. 110; Tire selection and rims for motor vehicles with a GVWR of 4,536 kilograms (10,000 pounds) or less. National Highway Traffic Safety Administration (NHTSA), Code of Federal Regulations, annual edition (GovInfo). 2006-10-01. S4.3: the placard shows the recommended cold inflation pressure. Retrieved 2026-11-01.
- UN Regulation No. 30 - Uniform provisions concerning the approval of pneumatic tyres for motor vehicles and their trailers (Revision 3). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.29/Rev.3. 2007-03-29. Annex 4: load capacity index. Retrieved 2026-11-01.
Last reviewed 2026-11-01. The full source list, with dates and file checksums, is in How the numbers are calculated. To report an error, email contactus@tiresizecalc.net.