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Slugbait
7th June 2024, 10:23 AM
Hi I have a 2015 Defender 130 and I'm getting a knocking sound coming from the transmission on power take up and Power off almost like backlash. I have checked the universals and the diff and the noise isn't coming from there. Any ideas would be greatly appreciated.

Cheers

Steve

DieselDan
7th June 2024, 01:40 PM
Knackered engine or transmission mount?

spudfan
7th June 2024, 06:44 PM
As it only occurs when adding power it could be one of the engine mounts but I have not come across this in a Puma. The heat shield on the turbo can rattle when the bolts loosen.
Cannot see it being an engine internal issue. If you have access to a ramp it would be easy but time consuming to just get a small pry bar and see if any thing is loose.
A very worn shop absorber bushing could be at fault but there are a lot of other bushing you could check when it is on the ramp.
When the PCJ fault was an issue this led to a rattle in the engine but you are well out of that batch.

Slugbait
7th June 2024, 06:55 PM
Thanks Guys

I hadn't even thought about mounts. I'll check them. I'm pretty sure it's not anything in the suspension or under the bonnet it's too central and to the rear of the transmission.

Cheers

Steve

spudfan
8th June 2024, 04:22 AM
Have a look in the seat boxes under the front seats. If (like me) you store stuff there it could be moving. Hopefully it will be something simple.

POD
8th June 2024, 09:29 AM
Check the rear suspension ball joint on top of the diff.

MLD
11th June 2024, 01:56 PM
in a defender, where would you start the list of things to check. Obvious that come to mind:

1) drive flange flogged out;
2) A frame ball joint or upper control arm chassis end bushes;
3) engine and transfer case mounts;
4) intermediate shaft between box and transfer if it's the original spud shaft and was assembled when lub was in short supply;
5) front radius arm bushes or bolts being tight. on mine a shagg radius arm bush transmits the noise through to the chassis under the drivers seat which is adjacent to the transfer case;
6) while you are under the front diff, check panhard bushes. That can be a noise but more often is associated with steering symptoms too.

DazzaTD5
13th June 2024, 11:01 AM
knocking on power on / power off sounds like either the ball joint above the rear diff.
Or rear diff itself which is by far way more common than the ball joint on a Defender TDCi (2007 - 2016).

BUT they are quite a clunk clunk driveline on that model, so as others have said it can be clutch, adaptor shaft, transfer case centre diff, rear diff.
a clunk on this model is a very broad statement.

JDNSW
13th June 2024, 01:22 PM
Should also point out that a dragging handbrake will result in any slack being more prominent.

Slugbait
29th July 2024, 04:26 PM
Hi I have a 2015 Defender 130 and I'm getting a knocking sound coming from the transmission on power take up and Power off almost like backlash. I have checked the universals and the diff and the noise isn't coming from there. Any ideas would be greatly appreciated.

Cheers

Steve

Update. I know it's been a while since I posted this but I had the Defender in the Mechanics over the weekend and it appears that the noise is what I thought, backlash in the Diff. I have it booked in on the 19th to be repaired. I'll keep you updated.

Cheers

Steve

jwb
3rd August 2025, 09:48 AM
In a similar vein. We have a new to us 2011 Puma 90 with around 90k km.

There is a clunk/thud whatever we find when the clutch takes up drive when changing up through the gears.
No problem on initial clutch engage
Happens on every up change from then
Nothing on down shift or when power on off in the same gear.
Rattly clutch? we think when idling

Checked over for RWC recently and shock bushes replaced
A frame bush renewed prior to purchase

I can get it on a hoist at some stage and been doing lots of reading on here and elsewhere in relation to clutch and gearbox output shaft in particular.

Will follow the diagnostics mentioned above and appreciate any and all thoughts as well.

DazzaTD5
4th August 2025, 11:30 AM
In a similar vein. We have a new to us 2011 Puma 90 with around 90k km.

There is a clunk/thud whatever we find when the clutch takes up drive when changing up through the gears.
No problem on initial clutch engage
Happens on every up change from then
Nothing on down shift or when power on off in the same gear.
Rattly clutch? we think when idling

Checked over for RWC recently and shock bushes replaced
A frame bush renewed prior to purchase

I can get it on a hoist at some stage and been doing lots of reading on here and elsewhere in relation to clutch and gearbox output shaft in particular.

Will follow the diagnostics mentioned above and appreciate any and all thoughts as well.

engine running, gearbox in neutral, foot off clutch, a rattle (at your km's) is likely clutch.
further to the above, turn ignition off and listen for a final rattle to a stop, then yes clutch is falling apart, eventually the springs will fall out and jam.