My blazer seems developing a humming noise from the front end, this is what i have checked so far

When jacked up the front wheel can be wobbled left to right and up and down - does this mean i need to change the front hub assembly??

When the wheel if off the front rotors can wobble about a little - is this correct??

And to top it all off it seems that a cv boot is leaking, i cannot see a tear in it I think the grease is coming from the clip - maybe a boot kit will sort this, pump it full of grease and replace the clip . any ideas?

or do you think the cv is the problem for the humming?

thanks for all your advice

MArcus

 

Your wheel bearing needs to be replaced. How many miles are on your Blazer? I would replace both since the other is probably not far behind in failing.
The rotor is held down tight by the wheel so yes it will be loose when the wheel is off.
While you are changing out the front wheel bearings consider new CV shafts as well... then you are done in there for a good long while.

 

Mileage is 110 000KM, i did spray grease the bearing the other day, i guess this has amplified the noise now

I did notice a little feathering to the outside edge of the drivers tyre, do you think the wheel bearing / hub assembly would create this problem?


thanks

marcus

 

Up/Down movement is definitely a hub assembly problem. This can definitely cause a hum when driving down the road. I would get that replaced first and then see if the left/right movement is still there. L/R movement with a good hub/bearing assembly is indicative of a steering component problem.

When the wheel is off, there will be play in the brake rotor. When you install the lugs, they sandwich the wheel and rotor between the lugs and the hub, holding them both steady. If the hub is wobbly, it needs to be replaced. Without the wheel and/or lugs, there is nothing clamping the rotor fast to the hub.

As discussed in another recent thread on CV shafts, if you have leaking CV boots, it is often best and most cost effective to replace the CV shaft with a remanufactured unit. The two piece boot kits are garbage and the single piece boot kits are often time consuming to install and some special tools are needed to crimp the clamps.