Car bearing numbers explained: 6203, 6301 2RS, ZZ and wheel bearings

Every bearing has its size printed on it. If you can read that number, you can buy the right one in any market in Pakistan, even without the old part in your hand. This guide explains the numbers, the letters after them, and what the shops actually stock. It is based on the 181 bearings on Nadir Autos' stock sheet in Gawalmandi, Rawalpindi.

The short answer

• 6203 is a deep groove ball bearing with a 17 mm hole, 40 mm across and 12 mm wide.
• 2RS means rubber seals on both sides. ZZ means metal shields on both sides.
• Wheel bearings on Suzuki cars use DAC numbers. DAC3668 is 36 mm inside and 68 mm outside.
• Tell the shop the full number, including the letters, and say whether you want Japan-made or China-made.

How to read a four-digit bearing number

Most bearings in a car are deep groove ball bearings: in alternators, AC compressors, water pumps, gearboxes and tensioners. Their numbers start with 6.

• The first digit is the type: 6 is a deep groove ball bearing.
• The second digit is the series, which sets how heavy the bearing is for its hole size: 0 is extra light (60xx), 2 is light (62xx) and 3 is medium (63xx).
• The last two digits give the hole (bore) size: 00 is 10 mm, 01 is 12 mm, 02 is 15 mm and 03 is 17 mm. From 04 up, multiply by 5: 04 is 20 mm, 05 is 25 mm, 06 is 30 mm, 07 is 35 mm.

So a 6304 has a 20 mm hole (04 × 5) in the medium series, and a 6007 has a 35 mm hole in the extra-light series.

Sizes shops in Pakistan stock most

These are the sizes with the most variants on Nadir Autos' stock sheet, with their standard dimensions:

Small bearings with three digits follow the same idea: a 626 is 6 × 19 × 6 mm, a 627 is 7 × 22 × 7 mm and a 629 is 9 × 26 × 8 mm.

What the letters after the number mean

The letters matter as much as the number. Two bearings with the same number but different letters are not the same part.

On the stock sheet you will see the same size in several versions, for example 6007 2RS and 6007 RKB. RKB is a brand, not a seal type, so always read the brand and the letters separately.

Wheel bearings: DAC numbers

Front and rear wheel bearings on most Suzuki cars are double-row angular contact bearings, sold under DAC numbers. The first two digits are the hole and the next two the outside diameter, in millimetres. The letters and numbers after that are the maker's own code for width and sealing, so give the shop the whole number.

These are the wheel bearings on Nadir Autos' stock sheet, and the cars they are listed for:

The Baleno and Liana both use a 40 × 72 mm front bearing, but the codes differ (DAC4072W-3CS35 for the Baleno, DAC4072-15CS74 for the Liana), so they are not interchangeable. The new Swift uses a hub-type rear bearing (ZA-28BWD05) instead of a plain DAC bearing.

A wheel bearing usually needs a new hub seal at the same time. Shops sell them by car: Mehran and ST308 seals (NOK and Chinese), and big and small seals for the Cultus and Margalla.

How to tell your wheel bearing is going

• A humming or growling sound that gets louder with speed
• The noise changes when you turn left or right
• Play or a knock when you rock the wheel by hand with the car jacked up

See the wheel bearing part guide for more.

Tapered roller bearings: 30205, 30305 and inch numbers

Five-digit numbers starting with 30 are tapered roller bearings, used where a bearing takes heavy side loads: older wheel hubs, differentials and some gearboxes. 30205 has a 25 mm hole and is 52 mm across. 30305 has the same 25 mm hole but is a heavier bearing, 62 mm across.

Numbers such as 11749, 44649 and 45449 are inch-size tapered bearings. They come in two pieces, the inner cone and the outer cup, and the cup has its own number. Ask for the cone and cup as a set.

Brands Pakistani shops stock

Across the 181 bearings on Nadir Autos' stock sheet:

The same brand can be made in Japan or in China, and shops sell them as different items at different prices. Nachi Japan and Nachi China are not the same bearing. If the shop quotes you a brand, ask which country it is made in. The country is printed on the box and usually etched on the bearing itself.

Avoiding fake bearings

Fake branded bearings are common. Be careful when:

• the price is far below other shops for the same brand and number;
• the printing on the box is blurry, or the brand name is spelled slightly wrong;
• the marking on the bearing is printed in ink instead of etched or laser-marked;
• the bearing feels rough, or spins with a gritty sound, when you turn it in your fingers.

What to tell the shop

1. The full number and letters from the old bearing, for example 6203 2RS or DAC3668-2RS. A clear photo works.
2. Where it came from: wheel, alternator, AC compressor, water pump, gearbox or clutch.
3. Your car and model year. Wheel bearings change between models and years.
4. The brand and country you want, or ask the shop to quote Japan-made and China-made side by side.

If the number has worn off, measure the hole, the outside diameter and the width with a vernier caliper. Those three sizes are enough for the shop to find the bearing.

Where to buy bearings

Bearing shops cluster in the main parts markets:

• Rawalpindi: 14 bearing specialists in Gawalmandi. See all bearing shops in Rawalpindi.
• Lahore: the biggest group is in Badami Bagh. See all bearing shops in Lahore.
• Karachi: around Old Haji Camp. See all bearing shops in Karachi.

Every bearing on Nadir Autos' list is in the bearings and seals catalogue. Prices change with the dollar rate, so ask for today's price: send one request and shops near you reply with their price and whether it is in stock.