Have This Weird Clunk/hit In The Back When Relase Throttle/apply Throttle

[robots]

Hey!

I've been having this weird issue, thats on my nerves for quite some time.

When I coast on light throttle and suddenly apply more throttle. Like WOT, I get this clunk/kick in the drivetrain.

Or if I coast on light throttle and release the throttle pedal quickly. I also get this clunk/kick.

First I can feel it. Its like some kind of play. Probably the rear subframe/differential, cause I can sense it coming from there. Also the sound is from the rear.

If I raise the rear of the car. And try to move rear wheels by hand. I can feel there is small play until the diff(Nismo 1way) engages and spins another wheel.

Something like ~1cm play. I can rotate a wheel ~1cm forward and backward without engaging anything.

Anyone had similar problem ? What should I look for.

Sydneykid advised to look into final gear/pinion gear alignment.

Before I had a s14 3.7 final gear viscous lsd I didn't have this issue.

Car is A31.

Thanks in advance!

[MYRB30]

Yep sounds like play alright. Rear sub frame bushes rooted I guess. Drivers side front, check that bush. Big job, pain in the rear. Ive done two cars for other people, now my own has gone aswell. Oh well, the joys of owning cars

[Lunatikk]

Also take a look at the centre bearing on the tailshaft, it can wear (moreso the actual rubber support that holds the bearing) & replicate the noise you're describing.

[robots]

You mean the driveshaft, right ? Driveshaft center bearing ?

I got alloy spacers in my rear subframe. So its basically solid. Can't be it.

[robots]

Lunatikk, where did u get your nick name from ? It means sleep-walker in russian.

[mattymagoo22]

have you got excess backlash in the diff? Reach under and see if you can twist your tailshaft back and forth, there could be a big clearance between your crown and pinion wheel, which is giving you the noise on and off the throttle.

[some_cs_student]

I have a similar problem on gear changes and the current suspect is the driveshaft appears to have some play in it, but I'm not quite sure yet...

[robots]

have you got excess backlash in the diff? Reach under and see if you can twist your tailshaft back and forth, there could be a big clearance between your crown and pinion wheel, which is giving you the noise on and off the throttle.

Hey. It seems about right.

How do I fix it ?

[R33GTST4Door]

i got the same problem atm... im thinking of replacing all the driveshafts, thats the only thing i havent replaced. im taking my car into the shop tuesday so ill know for sure whats wrong.

[DjeMz]

if its just a little noise dont worry... if it aint broken dont fix it!

i take it u have never been in a car with a 2 way diff?

[robots]

I wasn't talking about cornering. I'm talking about straight line stuff.

2ways don't chutter on straight line.

Also. When in 4th/5th gear. If I start to play with the throttle. around 2/3k rpm. Like on/off operation. I can make my car to jerk so violently. Its crazy.

Need more input here, guys !

Thanks!

[some_cs_student]

i got the same problem atm... im thinking of replacing all the driveshafts, thats the only thing i havent replaced. im taking my car into the shop tuesday so ill know for sure whats wrong.

Interested in this, I get a jerking at really low speed if I try to slip the clutch.

I have the clunk on release/apply of throttle, and on every gear change, the diff has been rebuilt but that doesn't seem to be the issue.

I *think* we found a little slack in the driveshaft, although it still needs to be confirmed.

[4drftn]

could be center bearing as said above, my commodore did a very similar thing, get it fixed or atleast looked at. locked diffs make the same sorta sound...

[sl33py]

Reach under and see if you can twist your tailshaft back and forth, there could be a big clearance between your crown and pinion wheel, which is giving you the noise on and off the throttle.

I have this exact same problem. I've apparently got a quarter of a turn in the driveshaft before the rest wakes up and turns with it Makes me jerk on gear changes and any momentum change, like I'm learning to drive manual. YUCK.

[DjeMz]

tailshaft centre bearing

[snappy_]

I've kinda got the same noise happening in my car, but one bloke said its the CV boots.

But i got around to checking it yet.

[Hibino]

Yeah I've got the same problem with my car. Haven't had a look at what it is yet... Very annoying though.

[Ben Dony]

i think its the subframe bushes. my car gtr had the same problem. so i put drift pineapples in