Okay, so I've got a 96 civic and need to get some advice. When turning, the front wheels make a knocking noise. Both of the CV boots are split wide open. A mechanic said I needed new CV boots but I think it's an axle issue. Problem is, I've got no knowledge of axles. Do I just need a new axle or is it something else?

 

if the boots are split open and the grease is gone and they are making a knocking or clicking noise i'd say yes he's right. i had a 92 civic with a split boot and i replaced the whole axle since the boot kits are kinda cheap and you don't know how long its gone without grease in the boot i'd replace the whole axle.

 

dito. replace both axles for a quick and easy fix.... rebooting them is a waste of time IMO. they are cheap enough at least. anywhere from 50-100bucks per axle range. just pull them off and take them down to get new ones.

only difference with a replacement one i noticed was that the center rubber piece was not on the replacement axle.... not sure what its there for. i havent noticed any side effects about it not being on the new axle tho.

 

The rubber disc that Addiction mentions is called a damper, which functions to reduce vibration of the axle when spinning at high rpm. An auto parts store called O'Reilly in my area ordered me a brand new replacement axle with a damper for $85. It takes about 5 days to arrive, if they don't have one in stock.