The short version
- Kit means very different things between brands, and nothing standardizes it.
- The items that strand people are small: the axle nut, a retaining clip, a seal.
- A good kit includes them. A bare bearing leaves you making a parts run mid job.
- Check the listed contents before ordering, not the word kit on the box.
What is in a wheel bearing kit is worth checking before you order, because the word covers everything from a single bearing to a complete corner of hardware.
What a wheel bearing kit leaves out matters here, since several of the missing items cannot be reused or improvised.
What kit can mean
| What you get | Commonly called |
|---|---|
| Bearing only | Bearing, sometimes still called a kit |
| Bearing plus seals | Bearing kit |
| Bearing, seals, axle nut, clip | Repair kit, complete kit |
| Complete hub with bearing fitted | Hub assembly |
| Hub assembly plus fasteners | Hub kit |
| Two corners of the above | Pair, axle set |
One brand’s kit is another brand’s bare part. The only reliable guide is the itemized contents list.
SKF, for example, states that its kits include the nuts, bolts and screws needed to complete the repair. Not every brand does that.
The items that actually strand people
Small, cheap, and impossible to continue without.
The axle nut. Frequently staked, crimped or angle tightened, and therefore single use. This is the number one reason a job stops.
The retaining clip. On pressed designs with a groove, a clip that got sprung wide may not seat again.
Seals. Never reusable on a serviceable hub, since the lip has taken a permanent set.
Cotter pin. Trivial cost, and a tapered hub cannot be safely finished without one.
Which of these are genuinely single use, and why, is on the single use parts page.
You find out the axle nut is single use when the car is on stands and the old one is deformed in your hand.
Ordering them alongside the bearing costs a few dollars and removes the entire problem.
What a kit will not include
Worth knowing what no wheel bearing kit contains, so you can plan the rest of the job.
A knuckle, if the bore turns out to be damaged. That is a separate and substantial part, covered on the bearing or whole hub page.
Anti-seize, which you should be applying thinly to the mating surfaces. Reasons on the corrosion page.
Grease, on a serviceable tapered setup, which you supply yourself and which has its own specification questions.
A dust cap, which is usually ruined during removal on a serviceable hub. That is on the dust cap page.
Tools, obviously, though a few kits include a driver or adapters.
Kits sold as pairs
A common listing format, and worth a moment’s thought before clicking.
Two corners priced together often looks like a saving against one part elsewhere. It is a saving only if you need both.
Wheel bearings do not fail in pairs the way brake pads wear in pairs, and the corners share almost no labor.
That argument is on the pairs page.
Trailer kits are a different product
A trailer bearing kit generally contains inner and outer cones, both cups, a seal and often a cotter pin, which is genuinely everything for one hub.
Complete pre-assembled hubs are also sold, which turns a bench job into a roadside one.
That option is covered on the trailer replacement page.
Ordering checklist
- Read the itemized contents, not the word kit.
- Confirm the axle nut is included, or order one separately.
- Check whether your design uses a clip, and whether the kit has one.
- Add seals and a cotter pin for any serviceable tapered hub.
- Open the box the day it arrives, so a shortfall can be fixed before you start.
That last step catches missing items, wrong variants and transit damage while there is still time.
Common questions
What is in a wheel bearing kit?
It varies completely by brand. It can be a bare bearing, a bearing with seals, or a full set including the axle nut and retaining clip.
Is what is in a wheel bearing kit standardized?
No. One brand’s kit is another’s bare part, so the itemized contents list is the only reliable guide.
What is in a wheel bearing kit most likely to lack?
The axle nut. It is frequently single use and it is the most common reason a job stops with the car apart.
What will never be in a kit?
A knuckle, anti-seize, grease for a serviceable hub, and usually a replacement dust cap.
Are pair kits a good deal?
Only if you need both corners. Bearings do not fail in pairs, and the two corners share almost no labor.
Are trailer kits different?
Yes, and more useful. They generally include both cones, both cups and a seal, which is everything for one hub.
When should I open the box?
The day it arrives. That leaves time to fix a shortfall or a wrong variant before the car is on stands.