The short version
- How many wheel bearings does a car have depends entirely on which design it uses.
- A modern car has four, one sealed unit per wheel, and each is bought and replaced as a single part.
- An older serviceable design has eight, because each wheel runs a matched pair of tapered bearings.
- Plenty of vehicles are mixed, with sealed units at one end and a tapered pair at the other.
This question sounds like it should have one number. The reason it does not is worth knowing, because the word bearing means two different things.
Sort that out and the answer falls into place, along with a lot of confusing parts listings.
How many wheel bearings does a car have today
Almost every car built in the last twenty five years uses a sealed hub unit at each wheel. Inside are two rows of rolling elements. You never see or buy them separately.
The unit is the part. So the honest count is four bearings, not eight rows.
You cannot open one, cannot repack one and cannot replace half of one. That is why the industry counts them as single items.
What is inside is on the hub assembly page and the double row page.
Why older cars count differently
A serviceable hub carries an inner and an outer tapered bearing. Each has its own race, and they face opposite ways.
They are separate parts with separate numbers. A full set for the car is eight bearings and eight races.
Trailers still use it. So do many older rear drive cars, and some four wheel drive front axles behind locking hubs.
The distinction runs through everything else on this site, and it lives on the serviceable page.
Counting by design
| Setup | Per wheel | Whole vehicle |
|---|---|---|
| Sealed hub units all round | 1 | 4 |
| Tapered pairs all round | 2 | 8 |
| Sealed front, tapered rear | 1 or 2 | 6 |
| Single axle trailer | 2 | 4 |
| Tandem axle trailer | 2 | 8 |
| Dual rear wheel truck | 2 per hub | Counted per hub, not per tire |
Read the last row carefully. Dual rear wheels share one hub. Four tires at the back does not mean four bearings back there.
Why the count matters when you buy parts
- Check what a listing includes. A tapered bearing may be sold with or without its race.
- Expect a kit on serviceable hubs, since inner, outer, races and a seal are usually bought together.
- Expect one box on a sealed hub, which arrives complete with its own seals.
- Order per corner, because left and right are often different part numbers.
- Never mix an old race with a new bearing, since they wear as a matched pair.
Tapered races press into the hub and stay there when the bearing comes out. Fitting a new bearing onto an old race fails quickly.
They are two halves of one part, and they wear into each other.
That situation is on the race removal page, and kit contents are on the kit page.
Do you replace them all at once
No, and there is no maintenance reason to. Bearings fail individually, driven by their own seal, corner and load history.
Serviceable sets differ in one respect. They need periodic repacking, and that is done to all of them together while the hubs are open.
The pairs question is on the pairs page, and doing all four is priced on the four bearing cost page.
Working out what you have
Take the dust cap off, or look at the back of the knuckle. A removable cap over an adjustable nut means a tapered pair.
A large flange with four bolts through the back, or one big staked nut and no cap, means a sealed unit.
The identification detail is on the dust cap page and the bearing versus hub page.
Common questions
How many wheel bearings does a car have?
Four on a modern car, one sealed unit per wheel. Eight on an older serviceable design, which uses a tapered pair per wheel.
How many are there per wheel?
One sealed unit, or two loose tapered bearings. Both carry load in two places, but only one is sold as two parts.
Does a sealed unit contain two bearings?
It contains two rows of rolling elements in one housing. You cannot separate them, so it counts as one part.
Can a car have both types?
Yes, and it is common. Sealed at the front with a tapered pair at the rear appears on many older rear drive cars and light trucks.
How many does a trailer have?
Two per hub, so four on a single axle and eight on a tandem. They are almost always the serviceable tapered kind.
Do dual rear wheels have twice as many?
No. Both tires mount to one hub, so that hub still runs a single set of bearings.
Should I count races separately?
For ordering, yes. Each tapered bearing runs on its own race, and the two should always be replaced together.