Fg turbo ute rear knocking

[Lithfkn]

I've checked wheel movement and all good in that area. Like I said I don't get any vibration or noises while driving, it's all on that initial take off and around really slow corners. I must say mine generally won't when cold but once its been for a good run like on a highway the driveline feels really slack and the rear knocks are petty loud.

 

There are tonnes of posts on here about this issue but no one has come back and given their solution haha

[powelmac]

I had exactly what your talking about, and it was the centre bearing. If its manual the driveline slop is standard as it gets warm, and you will always get a clunk if you disengage the clutch too quickly. If the noise/vibe relates to clutch movements, and/or you get in certain gears or more so in some than others then it's most likely driveshaft balancing (This wouldn't affect noise/clunk on take off though). I had a clunk when turning and it was my twin 3"exhaust slapping the chassis rail so worth checking that

 

I have a twin plate ceramic, built 2 piece shaft and true-trac diff with around 500kw, as you get familiar with the car and you learn how to drive it and you can drive around the slop easily from good clutch engagement and steady throttle movements.

 

I don't know where you are but pay G&J Drivelines a visit, and steer clear of pedders and go to experts like centreline suspension or advantage suspension if in Melb

[Lithfkn]

The car is dead stock except for the superpro stuff and konis and the knock was there before I changed everything. Definitely not the exhaust hitting. Its a very audible clunk from the wheel zone.

 

I know the bearing is starting to flog out, I can hear it wobbling at low speeds and get the driveline clunk/shunt if I don't try and really control it.

 

Been to pedders twice and they've just tried to upsell me. And the driveline joint was stumped.

 

Is it possible that the center bolt in the leafs has come loose? Is that a thing?

 

I'm in Geelong so Melbourne isn't too far away for me. Centreline in thomo is probably the closest out of those. I'm almost convinced its something with the leafs.

 

What centre bearing did you put in?

[Lithfkn]

So I've thinking about the gaps in the leafs and was wondering if anyone else's are like this? It doesn't look like they're clamping down firm enough? The top two have gaps but the bottom three look tight. Could this be the centre pin come loose maybe? 

 

 

 

 

I noticed the non xr utes have a different setup, two steel plates and no u bolt housing:

 

[OZYWALKER]

Ideally you want to do what the non xr has.
The bushes flog out so quickly.
The only issue you'll have is if you remove the metal saddle setup and bushes you'll have trouble lining the diff up as the bush is what centers the diff on the leaf.

[Lithfkn]

I reckon so. I can get some solid leaf saddle bushes from a bloke in QLD but that'll cost a bit. And I'm not convinced it'll fix the problem just yet. I feel like it needs a solid plate under and on top to pull them together more.

 

So I caught up with a mate who has an FG xr6 turbo ute and we compared leafs

 

These are his:

 

 

 

These are mine:

 

 

 

They look like two completely different leaf packs?

 

His has a steel plate between the leafs and saddle bush.

[OZYWALKER]

Guessing his is second hand.
Yours are normal and the same as my Ute was.
His have had the "helper" or "overload" leaf removed and the steel plate added to take up the slack between where the leaf was.


Removing the bushes was the best thing I did for tightening the rear end. If anything it will add noise which should help isolate the issue if that wasn't it.

[Lithfkn]

What did you put in its place? Steel saddle pads?

[OZYWALKER]

I didn't replace them.

Removed them and the steel saddle brackets completely.

Then drilled our a peice of round stock to fill the gap where the bush would have been between the leaf bolt and hole in the axle housing plate.

[Lithfkn]

Thanks mate

Do you have a pic of this setup?