R13 indicates the tyre fits a 13-inch diameter rim. The "R" stands for radial construction (the standard for modern tyres). For example, 165R13 means a 165mm wide radial tyre designed for a 13-inch wheel.

Yes, they're identical. When the aspect ratio (profile) isn't specified, it defaults to 80%. So 165R13 = 165/80R13. Both are 165mm wide with a sidewall height of 80% of 165mm (132mm), fitting a 13-inch rim.

The "C" stands for Commercial, indicating a reinforced light truck tyre with higher load capacity. 165R13C tyres typically have 6-8 ply construction and are designed for vans, trailers, and commercial vehicles carrying heavy loads. They're equivalent to LT (Light Truck) rated tyres.

Yes, with caution. 175/70R13 is 10mm wider with a lower profile, giving a very similar overall diameter (575mm vs 594mm for 165/80R13). Check wheel well clearance and note your speedometer may read slightly fast. Both fit 13-inch rims with 4.5-5.5 inch width.

Your tyres' combined load rating must exceed your trailer's gross vehicle mass (GVM). For a 2,000kg GVM trailer with 4 tyres, you need at least 500kg per tyre (load index 86+). For safety margin, use load index 90+ (600kg each). Always use LT/C rated tyres for trailers, not passenger tyres.

Passenger R13 tyres typically run 28-36 PSI depending on load. Light truck R13 tyres run 40-50 PSI when loaded to maintain their rated capacity. Always check your vehicle's door placard or manual for the manufacturer's recommended pressure, and never exceed the maximum pressure moulded on the tyre sidewall.

Yes, R13 is one of the most common small-diameter sizes and remains readily available. Unlike increasingly rare R10 tyres, R13 is still produced by multiple manufacturers in both passenger and light truck ratings. Tyre Dispatch stocks 7+ R13 sizes year-round.

R13 tyres typically fit rims from 4.0" to 6.0" wide depending on tyre width. 155/80R13 fits 4.0-5.5" rims. 165R13 fits 4.5-5.5" rims. 175/70R13 fits 5.0-6.0" rims. Check the tyre's sidewall or specification sheet for the recommended rim width range.