FIXED: Rear axle click clunk noise

JARblue

The reason I was looking for a TSB is because the dealer is looking for any excuse to not do this work. No TSB means no warranty coverage and would explain the response I got from them.

__________________

juld0zer

hmmm i reckon if you have the time, tools and confidence to do it then do it yourself. then you dont have to worry about all the what-if's that come after a dealer visit. eg. what if they rattle gunned the big nut on? or what if they didnt replace the single use items?

to this day i still struggle to understand how some moly grease applied to the flat mating face can magically cure this clicking noise that occurs whenever the axles are loaded/unloaded - which is clearly a rotational impact related noise. for the TSB to make sense in theory, the flat surfaces of the axle and the hub must be moving in and out on each application of the gas pedal (or side to side depending how you see it). It would make more sense if the instruction was to apply grease to the splines, but again for the splines to make that much noise there would have to be a huge amount of wear/misfit.

im no engineer but IMO the torque spec for the nut is way too low.

i believe that due to the sloppy design (pardon the pun), the constant loading and unloading of the axles particularly in forward motion creates an impact-gun like effect which breaks the nut loose. The only thing stopping the nut backing off completely is the soft cotter pin. Some models have an adjusting cap which resembles a large beer cap that goes over the nut and the cotter pin is driven thru the castellated slots of the cap. The cap is made of soft metal, not much stronger than the metal on your fridge door. The constant impact-gun like effect wears down the soft castellated slots which were once snug because the cotter pin was driven between them, holding the cap in place. Once the slots are worn, the cap becomes loose, as does the pin and the nut beneath. When the clicking noise re-emerges, the percussion from the nut to pin to cap makes the noise worse and slightly more metallic. This is why it begins as a dull clonk then becomes a full on metallic click with more distance accumulating. Nissan's choice of using a 'spring washer' IMO is also flawed. Its name implies it serves a springing function, which suggests it is promoting or at least allowing some lateral movement of the axle shaft inside the hub. This 'spring washer' is best described as a domed washer. It is not flat. Other manufacturers either have no washer or a conventional flat washer betwen hub and nut.

With further research on the applications of the nut fitted to our cars, i learnt that the torque spec is different on other vehicles (or even model years in the case of our 370z line). Therefore i concluded that it is safe to torque the nut up more than the FSM specification. Some people may have success with that alone. It didnt work for me but i've now been click-free for a long time and i'm glad i got to the bottom of it.

Sometimes you just have to take matters into your own hands because nothing anyone else does will satisfy you after all that you've been thru. the dealer might just go bonkers with the rattle gun and hand the keys back, charge you for regreasing the axles and you'll be pissed in a few months when it comes back