My Blazer has the dreaded wup wup wup sound and its my drivers side hub bearing. I want to order the lifetime warranty assembly with a quality name as I'm tired of the problems. I was tired and lazy after work this morning after working a twelve hour shift and decided to take the truck to the dealership.

They wanted 375.00 for the hub bearing and and 83.00 for labour with a warranty of one year. As they had my truck in the air they say they found a tear in the CV boot and that there is oil everywhere and if they fix the bearing it will probably go again from the fluid.

I decided against the repairs as the new bill would have been around 800 dollars(canadian dealerships and taxes) assuming they wanted to replace the CV axle, but I didn't ask after she told me the new bill. Is the hub bearing and CV axle one unit or are they to separate units? How do you tell if your CV axle is shot?

I looked at my CV boot tonight and could not see a tear or rip anywhere and the grease is from my balljoint as they were just lubed and the oil is from the oil cooler lines that are leaking. THe trucks wup wup wup sound increases when I turn right which leads me to beleive it's the bearing. I want to attempt the repairs myself as I used to do alot of my own work on my Mustang, but CV axles and hub bearings are all new to me and I would like to attempt to fix myself if I can. Any info or help appreciated sorry so long winded but that's usually how I post.

 

Well, I'd make sure that your CV is actually ok before moving forward. Typically, a worn CV will make a clicking noise during high steering angle turns. If you go to a large parking lot and do a series of tight, low speed turns in both directions and hear nothing, then the CV joint itself is probably ok. Now if the grease did in fact come from over-greasing the ball joints, then your boot should be fine. But just to check, take some rags and thoroughly clean the CV boot, inspecting all areas of it. If you see no abrasions or cuts, then your CV should be good to go. When you put everything back together, use never-seize on the bolts and contact surfaces between the hub and the steering knuckle, and the hub and axle. This will ensure that, if you ever do have to pull it apart again at a later date, things will go smoothly.

Now, onto the bearing. Really, the bearings aren't all that bad to change. You'll need something like a 35mm socket for the axle nut and I would recommend having air tools at the ready because the axle nut can be a bear to get off if you're doing it the old fashioned way. From there it's just disassembly. It may be interesting to get the wheel bearing off of the axle splines, but this is where some soaking with penetrating oil will go a long way. You may have to use a puller on it though so be prepared.

 

The bearings and CV's are actually relatively easy to do if you're somewhat mechanically inclined.

You'll really only need basic hand tools (the axle nut needs a 36mm DEEP socket). A few tips...

-Use a 1/2" breaker bar with a length of pipe on the end to loosen the axle nut (I put a brass drift through the caliper and into the vents of the rotor to hold in in place)

-If you have access to an air hammer with a punch, use that to push the CV back into the bearing. There's a small dimple at the end of the CV that you can put the punch into. Hammer away, it'll push the CV back about an inch, at which point, it'll be loose enough to get out once you've gotten everything else off.

-You can actually take the wheel bearing off without seperating the ball joints from the knuckle... a ratcheting 18mm wrench will help a lot, but it's not necessary.

The basic order of operations for replacing the CV and wheel bearing:

1. Loosen the lug nuts
2. Jack the truck up and put a jack stand under it
3. Pull the wheel off
4. Loosen axle nut
5. Remove brake caliper and rotor (tie the caliper up out of the way).
6. Unbolt the brackets for the ABS sensor wire and brake line
7. Push the CV back into the wheel bearing (either with an air hammer, or a sledgehammer and block of wood)
8. Unbolt and remove wheel bearing (if this is all you're planning on doing, you can reverse steps 1-8 and be done)
9. Unbolt tie rod end and move out of the way.
10. Place your jack under the lower control arm.
11. Unbolt upper ball joint (might need some persuasion to seperate from knuckle... pickle fork works great here. The pressure from the torsion bar will force the lower control arm down onto the jack, so having it up tight to the control arm with a bit of pressure on it is necessary)
12. Unbolt and seperate lower ball joint (sledgehammer on the top of the knuckle works great for me)
13. Move the knuckle out of the way
14. Tap the CV out of the differential (it's held in by a spring clip... you just have to give it a good tap outwards from the diff side. I use a pickle fork on the pot of the CV).

Reverse all these steps for reassemble. Make sure to properly torque everything down.

 

I didn't see any tears or rips in the boot itself. The boot was actually really clean no oil from the oil cooler lines had even touched that area, only underneath truck. The greasee i cleaned out was from overgreasing the balljoints so I believe I will change the bearing.

 

Jigg summed it up pretty well...its really easy.... I just changed my drivers side this past Sunday,and my experience with major repairs adds up to watching my dad change the other side for me last year. He showed up about 3/4 of the way through putting it all back together, and sure enough, I AM smart enough to fix my own truck....hehe.