2024 Nissan Z Perf - Torque reversal pop

[Technomancer]

Having an ongoing issue... It makes this mechanical pop when changing directions. Sounds like a dull thud when reversing, but a loud pop going forward. The videos don't do it justice and it feels worse than it sounds.
I can also make it happen while cruising if I let off the gas and hit the pedal again so I don't think it brake pad related.
Had it at the dealership multiple times already and about to go for round 3 - just looking for additional opinions.
I was underneath and checked torque on all the bolts on the rear end - found some loose on the brace but the issue persists

 

[5amp5on]

Yeah that does not sound good or "normal". Beyond that confirmation I'm no help on diagnosis.

 

[trackratZ]

Do you have aftermarket catback AND underbody brace? Others had those touching each other, clearance issue. Or, maybe driveshaft, how many miles on the Z?

 

[Technomancer]

Do you have aftermarket catback AND underbody brace? Others had those touching each other, clearance issue. Or, maybe driveshaft, how many miles on the Z?

Aftermarket exhaust, yes. OEM brace. I double checked the exhaust wasn't resting or rubbing on anything. no issues there from what I can see

 

[Technomancer]

Do you have aftermarket catback AND underbody brace? Others had those touching each other, clearance issue. Or, maybe driveshaft, how many miles on the Z?

Coming up on 20K km. It's definitely something in the back end. It won't do it with the clutch in, only when I send power to the diff. sometimes it will pop when going around corners as well.
Also, weirdly enough, some times it goes away. I can drive to work without a sound, then acts up on the way home.
Ambient temperature doesn't seem to affect it either - happens at 6 degrees just as much as it does at 27

 

[KrackaC8]

Have you checked or replaced your rear differential fluid? If not, you're likely due for a drain & fill. Has the dealership been able to isolate the noise? To be, it sounds like something is binding... I'd check the driveshaft & axle joints as well.

 

[Technomancer]

I'll have to check the fluid once I get it back if the dealership doesn't.
They did the re-greasing with the M77 last year and installed newer revision axles as per whatever TSB they were following.
I took them apart this year and did the same thing - no change.

There is some backlash in the drive train when I move it by hand with the rear wheels in the air - I'm not sure how much is supposed to be normal though.

 

[Neutr0n]

nissan had the same problem when i worked there back in 2007 lol we were told to grease the splines with moly grease

 

[Drago86]

Is it the e-brake dragging a little? The E-brake has front to back play in it even when engaged all the way and will pop a little if you rock the car back and forth with the e-brake on. There is slight gaps in the tabs the shoes are mounted too that causes the play.

 

[Pragmatist]

If it was an older car would say it was a motor mount.....

 

[trackratZ]

I'll have to check the fluid once I get it back if the dealership doesn't.
They did the re-greasing with the M77 last year and installed newer revision axles as per whatever TSB they were following.
I took them apart this year and did the same thing - no change.

There is some backlash in the drive train when I move it by hand with the rear wheels in the air - I'm not sure how much is supposed to be normal though.

I think you found the problem area.....

 

[SleepyD7]

I could get my Z34 to pop or creek similarly whenever I disengaged my parking brake and started to move. (?)

 

[Technomancer]

nissan had the same problem when i worked there back in 2007 lol we were told to grease the splines with moly grease

Yeah that been done twice now lol

 

[Technomancer]

Is it the e-brake dragging a little? The E-brake has front to back play in it even when engaged all the way and will pop a little if you rock the car back and forth with the e-brake on. There is slight gaps in the tabs the shoes are mounted too that causes the play.

I can ask the dealer to look into that. Or I will once I get it back

 

[Technomancer]

I think you found the problem area.....

Hopefully not, but at least it's under warranty.