Clunking Noise

[Skadoosh!]

Hey guys..

Wondering if anyone can help me out i own an R33 Skyline GTS25T, and recently when i have been starting to first roll in first gear, or in reverse or when im stoping. There has been a clunky sort of noise coming from the rear. It sounds similar to if you let your toolbox sit loosely in the boot and when you stop and move it slides around hitting things.

After some advice or help if possible

Cheers

[GTR-N1]

Can you try travelling at about 20 Km/Hr and lightly accelerate > decelerate > accelerate > decelerate etc and see if there is that clicking/clunking noise at the rear still?

[heslo]

Obviously you've checked the boot for anything loose? Could have to do with your suspension system, not necessarily the suspension itself but a broken swaybar mount, etc. Got anywhere you can take it to for a look?

[Birds]

Sounds a bit like the diff to me...

But answer Terry's questions first.

Sometimes diff clunks/whines have a habit of disappearing under acceleration or at high speed.

[Nimmo]

I have the same issue and I do hear the sound when I'm slowing down and also sometimes when I stop at lights, kinda sounds like a little 'donk' (it will do this once each time). It can also hear it when I take off sometimes too, it's very noticable when the car is cold and I roll out of the garage.

[GTR-N1]

Differential gear oil should be inspected every 10,000Km

LSD gear oil (according to the manual) has a higher viscosity & temp. threshhold and should be changed every 40,000Km

If LSD Gear oil gets too thin, gets too low or breaks down, you'll hear clicking between acceleration & deceleration & back again whilst travelling at low speed.

[mitch32]

Differential gear oil should be inspected every 10,000Km

LSD gear oil (according to the manual) has a higher viscosity & temp. threshhold and should be changed every 40,000Km

If LSD Gear oil gets too thin, gets too low or breaks down, you'll hear clicking between acceleration & deceleration & back again whilst travelling at low speed.

This also started to happen to me after I changed my subframe bushings and diff bushings to aluminum.

Maybe one of your bushings is completely finished.

[Nimmo]

Differential gear oil should be inspected every 10,000Km

LSD gear oil (according to the manual) has a higher viscosity & temp. threshhold and should be changed every 40,000Km

If LSD Gear oil gets too thin, gets too low or breaks down, you'll hear clicking between acceleration & deceleration & back again whilst travelling at low speed.

I don't' want to hijack this thread but just to add to my previous post. Ever since I bought the car (December 2007) I have regular services done on my car and I know the last service all fluids were changed, it's nearly time for another one so I'll mention it to the mechanic and see what they think.

I can't be 100% to say that this was happening from the day of purchase, I'm also guessing if it is that the oil has gotten too thin this won't be resolved simply by changing it now would it.

Does it mean it's time for a new diff?

[Muff]

nope not at all... your old diff is still quite good, from the sounds of it, people might disagree with me but if ur low on oil and its clicking you know its engaging... prob not the best thing to have but wont hurt it too much,.check your oill and dont be a cheap ass... buy the good stuff,... its a lot cheaper than a new diff.

if the clicking keeps going . look at shimming it up .

but in my case there were jsut some loose subframe bolts...

when you put rose jointed camber arms and such items there will always be a little clunk.... when you roll back and break or forward and break...

good luck

ps if ur diff starts wineing then youve got problems....

[Skadoosh!]

Thanks for the help..

Terry GTR-34: i tried what you said, with the 20km accelerate and decelerate. It does it occasionaly, but more so when i first take off and under braking.

Any suggestions or help.

Thanks for the assistance guys. Ive only just got my car and i'm not very mechanical, and want to lear more, so any help is appreciated.

Cheers

[33driver]

sounds like the same issue with mine, but mine is much worse.

Besides the diff being stuffed, I have WAY to much backlash in the diff, but a 2nd hand one, preshimmed ready to put in when i get a chance

[GoodOldR32]

might be ur UNI joints also, always good to check them out to.

[GTR-N1]

^^^The centre universal joint on the tailshaft has been known to go weak on the R33 with rapid acceleration.

On a hoist, your mechanic can push up on it from underneath to 'feel' if it's soft or...

you yourself can drive the car along a freeway and say...

a) drive for 10-20sec at constant 100 Km/Hr

b) do the same at 110 Km/Hr

c) do the same at 120 Km/Hr

d) do the same at 90 Km/Hr

...and if you feel vibration through the car, you may require a replacement tailshaft.

If so, it shouldn't cost much or require much time to replace it.

Make sure it's the same part that corresponds with the same model of your car. For instance, the tailshaft on a R33 GT-R V-Spec is different from that on a non-V-Spec.

Position of cup & axis is important too. Better still, let your mechanic do it if it's a tailshaft. Labour time is quick.

Get the mechanic to replace your diff oil whilst you're at it. It might only be this after all.

[Skadoosh!]

I tried that and there was no vibration through any of those speeds. Does that mean its just diff related.

Does anyone know any good mechanics i can take it to.. One that wont take advantage of my lack of knowledge anyway.

Im in the wollongong are but i dont mind driving to sydney..

[GTR-N1]

I tried that and there was no vibration through any of those speeds. Does that mean its just diff related.

Does anyone know any good mechanics i can take it to.. One that wont take advantage of my lack of knowledge anyway.

Im in the wollongong are but i dont mind driving to sydney..

Wollongong to Kirrawee ain't far!

Garry is the technician at Just Jap 02-95450532

Call Darron, Steve, Tim or Daniel to make a booking. They won't charge you any steep hourly rate either. Very fair and...

Most of all, good diagnostician.

If you have a real low lip on the front, just take the entry gutter at an angle.

101 Bath Rd Kirrawee

Make sure you tell us the results!!!

[-Jimmy-]

I had the same problem so I got the car checked out, and we diagnosed a centre bearing in the tailshaft had completely shat istelf, as well as the uni joints on either side of the shaft.

So I got that replaced with a custom 1 piece shaft, very happy and there wasn't any vibrations when taking off etc, but the clunk is still there.

I think I can safely say my LSD needs some new oil? It's had a hell of a workout this year as I have started drifting...