Fg turbo ute rear knocking

[arronm]

Springs look fine, must be the diff bush.....

[OZYWALKER]

Thanks mate
Do you have a pic of this setup?

Nope. Looked the same as that non xr pic less the spacer plate.

[Lithfkn]

I bit the bullet and threw in some solid steel saddle bushes and it hasn't made a difference to the sounds. I did notice that between each leaf through the middle there are steel plates, maybe 1mm thick. That's what's causing the illusion that there is gaps in the leafs. Is it normal that they have these thin plates through the middle? My mates leafs are completely sandwiched together.

 

Also noticed when jacking the rear up the wheel has some back and forth movement, a couple mm. But not in and out. Is this just the slack in the diff/gears?

 

Also got a centre bearing as that has collapsed from the top.

[Evster]

To the OP I had similar symptoms in my FGII xr6t Ute with 90k on it, though mine is an auto. Ended up requiring a new LSD and center diff bearings, which completely eradicated the noises. The car is extremely quiet to drive now. 

[Lithfkn]

Thanks

 

Was it the clutches/plates in the diff that were buggered?

[Evster]

He mentioned something about the plates but it was back at the start of the year so I don’t recall exactly. Sorry mate.

[Lithfkn]

Thanks mate. If you happen to remember or find out could you hit me up? I'm reading a lot about clutch plates knocking.

[JasonHyde]

I have a FG MKII NA Ute doing the same sort of sounds. Multiple clunks on acceleration and a single clunk -sometimes- on decel. Doesn't happen when car is cold, and happens a lot if I'm in traffic moving at 20-40kph. have 68k on the clock and have had the sound for a fair while now. Finally took it to a mechanic the other week to which they checked over the whole thing and didn't find an issue other than "it's your leaf springs". He didn't really have an idea as to why they were causing a sound in particular. When listening it definitely does seem like it's coming from the springs on drivers side, but at the same time the clunk on takeoff isn't just a single clunk, it will go sort of CLUNK-clunkclunkclunkclunk sometimes. Also noticed sometimes when pulling up to a light slowly, the closer I get to stopping I get a clunk..clunk...clunk.....clunk. It's really weird and hard to replicate. Also you can hear a thunk in the rear when going over a speed bump or a decent bump in the road, almost like something is bouncing in the tray. Haven't tried much yet apart from getting the diff oil changed, which did nothing. If anything the noise got slightly a bit worse in traffic. Maybe I'm thinking them having the springs fully unloaded on the lift made it worse somehow? I have no idea. I'm pretty useless with cars if I'm honest but I'm learning a hell of a lot in the process of trying to find the cause and solution to this. Going to check everything is tight underneath, despite the mechanics saying everything is tight and nothing is worn. Might try to put something between the springs or something. Bleh.

Edited 31/10/19 08:11 AM by JasonHyde

[camo86T]

19 hours ago, JasonHyde said:

Also you can hear a thunk in the rear when going over a speed bump or a decent bump in the road, almost like something is bouncing in the tray. 

Check spare wheel is tight underneath for this noise

[Lithfkn]

On 31/10/2019 at 7:11 PM, JasonHyde said:

I have a FG MKII NA Ute doing the same sort of sounds. Multiple clunks on acceleration and a single clunk -sometimes- on decel. Doesn't happen when car is cold, and happens a lot if I'm in traffic moving at 20-40kph. have 68k on the clock and have had the sound for a fair while now. Finally took it to a mechanic the other week to which they checked over the whole thing and didn't find an issue other than "it's your leaf springs". He didn't really have an idea as to why they were causing a sound in particular. When listening it definitely does seem like it's coming from the springs on drivers side, but at the same time the clunk on takeoff isn't just a single clunk, it will go sort of CLUNK-clunkclunkclunkclunk sometimes. Also noticed sometimes when pulling up to a light slowly, the closer I get to stopping I get a clunk..clunk...clunk.....clunk. It's really weird and hard to replicate. Also you can hear a thunk in the rear when going over a speed bump or a decent bump in the road, almost like something is bouncing in the tray. Haven't tried much yet apart from getting the diff oil changed, which did nothing. If anything the noise got slightly a bit worse in traffic. Maybe I'm thinking them having the springs fully unloaded on the lift made it worse somehow? I have no idea. I'm pretty useless with cars if I'm honest but I'm learning a hell of a lot in the process of trying to find the cause and solution to this. Going to check everything is tight underneath, despite the mechanics saying everything is tight and nothing is worn. Might try to put something between the springs or something. Bleh.

Does yours have an LSD?

 

Mine is definitely most noticeable from the passenger side wheel area but will sometimes get the double clunk. I got the centre bearing done and that eliminated some things but the rear clunk is still there.