Diagnose this noise! Transfer case or gearbox whir/whine?

**carpdvl** · 16th September 2019, 09:25 PM

Hi all,

So I have done fairly extensive investigations on a noise that began in my driveline about 3 months ago on a trip to the snow (well... it at least became very apparent then). Initially I thought it was front diff but have since narrowed it down based on a bunch of tests. The car is a 2011 Puma 2.4 that has done 96k.

Frustratingly, I dropped it to a well known independent locally to fix the noise and install a new clutch. Ended up spending just shy of 3k having the TC and gearbox pulled apart (note that also includes fitting a new clutch in labour costs). Importantly, same indie did a full TC rebuild (seals, bearings etc) a year prior so the cost did not include cost covered by the warranty on the labour and parts on the TC...

The full work supposedly uncovered the following:

Gearbox was fine (incl. all bearings), needed new detent springs and obviously seals
Transfer case intermediate shaft bearing was kaput after a year (wish had looked at this prior to gearbox...)

And that's about the extent of it...

Within about 5 minutes of getting it back and overcoming the joy of having my toy back dread filled me as I realised I could still hear this whine. Took it back in immediately and was told "that is weird" and "that doesn't sound like a bearing" and "drive it a while and see if it goes away - if not bring it back in"

I don't want to name the indie as this isn't aimed to beat up on them - I know **** like this happens and you can just miss it.

BUT in the interest of getting a further opinion:

Can anyone get closer to an accurate diagnosis? Here are the symptoms (with my assumptions):

Whining noise that increases with road speed (does not vary with RPM - rules out input shaft in gearbox)
The noise is present when the TC is in neutral and rowing through the gears (rules out output shaft in TC, diffs, handbrake etc. - so now we have output shaft in gearbox, input shaft in TC and intermediate shaft)
Noise is not present if both gearboxes are in neutral and I roll it up to 60kph+ down a hill (again disqualifies diffs and output shaft in TC + handbrake etc)
Noise increases significantly when in low range - almost to the point when getting up to 50kph or so in 6th it sounds like a carnival ride
Noise seems to become more "whirring" when the clutch is engaged (i.e. when I let go of clutch and it is in gear) but still whines when clutch is stomped in

On which basis it seems like it is most likely transfer case related but still doesn't isolate the output shaft on the gearbox I guess...

I have uploaded some videos from tonight driving in low range. The noise is a high pitched whining noise almost spinning-top like:

From 10 seconds you can hear it in this one like its trying to take off.

Can hear in this one decelerating at 9 secs in

Can hear from when I grind the gears briefly at about 10 seconds in

Any help please! Would be great to have in mind what I want done when I take it back to be fixed properly...

Cheers in advance

carpdvl

**Wicks89** · 16th September 2019, 09:57 PM

NFI tbh, but given you said it occurs when both cases in neutral but car is rolling could be the shim adjustment of the centre diff, as in the spider gears inside the centre diff. But probably wouldnt expect that unless it had done a lot of kms.

but again, NFI. unless the noise is really killing you if aint broke just send it I say. You could (and already have) spend thousands chasing just a noise when everything functions correctly.

One thing I have found after a couple of rebuilds of my LT230 is that the Ashcroft 'master rebuild kit' is actually a 'Most of the parts you need, but not all of them kit.' In order to truly rebuild the tcase you need to check tolerances on almost every single internal component and replace if necessary - an expensive exercise and time consuming. So you actually need to break the case down, measure all components and then order the bits that are worn out and the relevant shims required etc.

All that for a case that is actually functioning perfectly fine.

So if the mechanic is just using the rebuild kit you supplied that may not have all the shim kits etc, he may just be re-using the factory shims which could be worn and producing this noise.

but again, I have NFI and I dont actually know anything about pumas etc.

**carpdvl** · 16th September 2019, 09:59 PM

Originally Posted by Wicks89

NFI tbh, but given you said it occurs when both cases in neutral but car is rolling could be the shim adjustment of the centre diff, as in the spider gears inside the centre diff. But probably wouldnt expect that unless it had done a lot of kms.

Cheers wicks. When both in neutral and coasting the noise isn't present. I assume that discounts the centre diff setup

Good point I should mention the car has done just shy of 96k!

**Wicks89** · 16th September 2019, 10:06 PM

Originally Posted by carpdvl

Cheers wicks. When both in neutral and coasting the noise isn't present. I assume that discounts the centre diff setup

Good point I should mention the car has done just shy of 96k!

Yeah I dont know about discounts it but works against that theory.

It's hard through video but the noise doesn't sound like driveline, sounds like a noise aircon fan or something in the video. Maybe I got rocks in my head.

**Blknight.aus** · 17th September 2019, 03:51 AM

tcase intermediate bearing or a miss shim of the mainshaft in tghe box

**carpdvl** · 17th September 2019, 07:06 AM

Originally Posted by Blknight.aus

tcase intermediate bearing or a miss shim of the mainshaft in tghe box

On the basis it was making a very similar noise when I dropped it in as to now, and the indie said one of the intermediate bearings was kaput, I was thinking along the same lines... But it is bizarre that it would be gone immediately so perhaps correct on the box having been assembled incorrectly

I'm thinking the best way to check now will be to drop the tcase off and run it up with just the gbox in place?

**4bee** · 17th September 2019, 07:35 AM

After spending that sort of loot I bet your heart dropped/stopped when you heard it once again?

FWIW & it may not be remotely connected, I had a whining noise on my D1 & fitted an Ashcroft Oil Catcher to the rear of the transfer case. (input bearing?????) Job done (for mine).

Catcher consisted of a round plate with an open topped tube welded to the rear which caught & deposited oil to the bearing & shaft proper. Later fix was to cross drill the shaft IIRC.

**carpdvl** · 17th September 2019, 08:17 AM

Originally Posted by 4bee

After spending that sort of loot I bet your heart dropped/stopped when you heard it once again?

FWIW & it may not be remotely connected, I had a whining noise on my D1 & fitted an Ashcroft Oil Catcher to the rear of the transfer case. (input bearing?????) Job done (for mine).

Catcher consisted of a round plate with an open topped tube welded to the rear which caught & deposited oil to the bearing & shaft proper. Later fix was to cross drill the shaft IIRC.

You aren't wrong.

To complicate things further the new clutch or perhaps even it's the gearbox has begun making a pitter patter / chugga chugga /rattle noise when foot is off the pedal just sitting in neutral. Goes away when depressing the clutch...

Diagnose this noise! Transfer case or gearbox whir/whine?

Was planning on going away this weekend but I guess that grounds those plans

**PhilipA** · 17th September 2019, 08:26 AM

Just a suggestion.
When my pinion bearing let go on my M3, the mechanic put the car up on a hoist and started it up and ran through the gears.
They and I could spot where the noise was coming from with the old screwdriver stethescope .
Regards PhilipA

**4bee** · 17th September 2019, 08:42 AM

Ah the good old Screwdriver Stethoscope! A tried & tested method without all the bull****.

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