CV joints - how to inspect them?

[NielsGalan]

Hey guys.

I'm wondering if there is a simple and reliable way to inspect the cv joints on the rear axle. I'm thinking of replacing them, but for once I want to be sure they need replacing before doing it. I've done the opposite a couple of times too many already :-)

Thanks in advance,
Niels

[bad_manners_god]

Well, check for the obvious signs of wear, espically the boots, turn the wheels while on jack stands and inspect the boots for cracks and cuts.

Apart from that, you would need your axle's specs for thickness to measure with a micrometer or vernier caliper (if you have access to those) to make sure they are within spec.

[NielsGalan]

Here comes a stupid question:
Why are the boots so important?? Don't they "just" prevent dirt and **** to enter the joints/bearings?

Or does a "healthy" boot mean that the joint most likely is fine?

Good boot=No **** enters the joint=Good cv-joint?

[attack eagle]

I have no idea what he wants to measure with a vernier.

bad boot = replacement.
noise= replacement

[Washburn]

The boot not only keeps crap out, it keeps the good stuff in...grease. Like was already said. Good boot and no noise = do not replace. Torn boot, and a clicking noise = replace.

[bad_manners_god]

I have no idea what he wants to measure with a vernier.

bad boot = replacement.
noise= replacement

Measure the thickness of the rod between the 2 boots

[stilljester]

Measure the thickness of the rod between the 2 boots

Why would the diameter of the shaft change?

[bad_manners_god]

Why would the diameter of the shaft change?

Rust

[attack eagle]

good god man, if they are all rusted up to the point of flaking, then they should be disposed of... and you might want to trash the car too :)

[bad_manners_god]

good god man, if they are all rusted up to the point of flaking, then they should be disposed of... and you might want to trash the car too :)

Exactly, that's why you measure them with the vernier to see if they are within spec.

[BigKriss]

the boot could be still good and the cv joint is no good. thats what is wrong with my car.

[Ross]

There is no correlation between the axle safts rustiness or diameter and CV joint wear.
The wear occurs on the balls and cages within the boot. Pretty much like everyone else has said, if it has a good boot and is smooth while rotating(no clicks, etc.) it's fine.
They don't last forever and can wear out even with a sound boot but not often.

[stilljester]

Exactly, that's why you measure them with the vernier to see if they are within spec.

Could you please share the BMW spec for this condition? Thanks

[bad_manners_god]

Could you please share the BMW spec for this condition? Thanks

I'll check Mitchell when I get to school monday morning and post back.