a couple of days ago, my wife noticed a quiet knocking sound as she was driving our '08 Mazda CX-9. The sound got worse in the last day or so, and to me it sounded like it was coming from the rear of the vehicle. I jacked up the car to do a quick visual, and sure enough the left (drivers) side rear CV axle looks bad. The boot closest to the differential is covered in grease, though I couldn't find a tear in the boot itself. Is the replacement process something that can be done by a slightly above average home mechanic? Might there be another issue I am not seeing?
My car has 160000 miles.
My car has an automatic transmission.
Hi there - it’s likely the grease on the CV joint boot is grease from inside the boot, and also possible it’s from a leaking differential seal. Based on the noise your wife observed, more thank likely, it is the CV joint failing. I would recommend a CV axle replacement by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs. This repair requires some specialized tools to press the axle out, and back into the rear hub, in addition to safely supporting the vehicle while working underneath.
Have a car question? Get free advice from our top-rated mechanics.