Thumping noise

mazda
noises
wheels
protege5

#1

I have a 2002 mazda protege 5 that makes a thumping noise from what seems to be the right front passenger side. the noise/feeling in the floorboards used to eminate the worst at around 35 mph but would “work its way out” as we went faster and eventually the road noise would drone it out and the feeling went away. when going 35 mph and turning, the noise and thumping feeling would go away. I took the car into the shop, the mechanic said the half shafts were tight, the wheel bearings were good and the cv joints were good. he said that he repacked the half shafts, and now the noise has changed.



the noise now is what seems to be two metal discs spinning against each other smoothly (when i’m driving straight), and the thumping now happens when I turn left or right. it happens at all speeds… any thoughts what this might be? why did it change? seems to me it has to be related to the half shafts since the noise changed and generated a new noise when he “repacked” them.


#2

You need the half shafts replaced. At another shop.

The damage to the wear surfaces of the half shafts cannot be corrected by repacking them. In simplified terms, the shaft (axle assembly) Constant Velocity joints are constructed sort of like a ball joint with slots in both portions, in which are balls that move within the slots as the shaft portions rotate at an angle relative to one another. If the lubrication is lost and/or contamination gets in, damage occurs to the surface of the balls, the slots, and the “races” that keep the balls in their places. “packing” the joints will not repair the damage.

Beyond that, checking that the half shafts are “tight” is not a valid way to check for bad CV joints. If the protective boots are torn (they usually fail in the inside folds of the bellows and finding a tear requires pushing the bellows sideways and looking for one", and there’s noise, it’s a pretty sure sign of a damaged joint. The only visual way to confirm that would be to remove the half shaft, clean and disassemble the joint, and examine the surface of the balls. Way more expensive than replaing the half shaft.

You need another shop.