So about two months ago, I did a whip round and changed all the oils on the K powered freelander.

The IRD I changed to the specified GL5 75W90 and thought nothing of it - it was squeaky clean inside, so much so that I thought it may have been a rebuilt unit.

Fast forward a couple of months and I get it onto the motorway for the first time for a proper run and exceed a particular speed. (I rarely take the hippo on long distance runs, they're an excuse to get the RX8 out.)

Hit 75-77 mph and a godawful bearing noise started up from the gearbox area, completely invasive into the cabin and an awful din on the ears.

Went round and physically checked everything, and apart from some play in the IRD->Gearbox connection (no play at all in the crown/pinion wheel out the back of the IRD) I couldn't find anything that was obviously duff. I suspect the nearside inner CV joint is on it's way out, but it's not bad enough to make that kind of din yet.

So, on a hunch, I dropped the gearbox and IRD oil again. Gearbox oil was perfectly clean and tidy, not a mark on it, dropped the IRD, metal shavings on the plug. As much oil came out as went in, so it's not escaped anywhere, and the right amount went in. Double checked the bottle that went in and it's definitely the correct stuff.

WTF?

Flushed it out and replaced it with Halfrauds 15w40 engine oil a temporary stop gap to get me through the next couple of days (it's about equivalent to 80W90 gear oil) - perfectly silent, zero transmission noise at all from the hippo now.

Seriously annoyed, sounds like if I'd kept driving it it'd have lunched the IRD. I've had this before in the past, I'm not sure if all oils are equal, and this is a hard lesson to buy proper stuff. Having said that - I've had it in the past where big brand name (correct grade) oil caused the LSD on my RX8 to aggressively lock when it shouldn't.

What brand was it ?
Mike

I'd be checking tyre pressures and doing the OWUT just to eliminate the VCU.

How could you get play on the "IRD->Gearbox connection"? There's 4 substantial bolts mounting the the IRD to the gearbox (plate), if there's any play, presumably a couple of these are loose and could cause all sorts of grief on the input and LH wheel output shafts.

Nodge68 said:

I'd be checking tyre pressures and doing the OWUT just to eliminate the VCU.

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Currently in 2wd - as I'm in the middle of doing the second VCU drain!

GrumpyGel said:

How could you get play on the "IRD->Gearbox connection"? There's 4 substantial bolts mounting the the IRD to the gearbox (plate), if there's any play, presumably a couple of these are loose and could cause all sorts of grief on the input and LH wheel output shafts.

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When I spin one of the wheels I can see the gears moving inside the IRD immediately - but theres a second before the box takes up the slack - I suspect the usual amount of play in the PG1 final drive. They were all pretty bad at the diff once well worn!

B34R said:

When I spin one of the wheels I can see the gears moving inside the IRD immediately - but theres a second before the box takes up the slack - I suspect the usual amount of play in the PG1 final drive. They were all pretty bad at the diff once well worn!

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Ahh right the gears rather than units have play. The diff gearing will turn the final drive gear 3.2 times faster than the wheel. That will then be be taking up slack 4(?) times faster within the input/output shafts. Assuming you still have 1 wheel on the ground and the car in gear, with ratios varying from 3.2 to 12 - if there's much slack (ie you can turn the wheel a fair bit) then presumably that's worrying! I may jack up mine to see what play there is

Maybe we need another "VCU test results" type page saying how much play there is in everyone's transmission!

GrumpyGel said:

Ahh right the gears rather than units have play. The diff gearing will turn the final drive gear 3.2 times faster than the wheel. That will then be be taking up slack 4(?) times faster within the input/output shafts. Assuming you still have 1 wheel on the ground and the car in gear, with ratios varying from 3.2 to 12 - if there's much slack (ie you can turn the wheel a fair bit) then presumably that's worrying! I may jack up mine to see what play there is

Maybe we need another "VCU test results" type page saying how much play there is in everyone's transmission!

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It was particularly the gearbox side wheel (uk passenger side) that had the slack in, would be interested to know how much slack others have!

Hi mate, I dont think any of the tests you have dome so far would indicate an issue in the IRD at all.
I presume the IRD oil was clean ? - some metal shavings are not unusual at all and indeed can be expected.
The noise you describe would tend to indicate the cv joint or a n other area - it would not make me think IRD at all.
Noises such as you had can occur at certain speed and load conditions that cannot be repeated easily at the same speed due to the differing load.
You already say you suspect the NS cv as an issue, I would not -a t this stage consider the ird a suspect.

Joe_H said:

Hi mate, I dont think any of the tests you have dome so far would indicate an issue in the IRD at all.
I presume the IRD oil was clean ? - some metal shavings are not unusual at all and indeed can be expected.
The noise you describe would tend to indicate the cv joint or a n other area - it would not make me think IRD at all.
Noises such as you had can occur at certain speed and load conditions that cannot be repeated easily at the same speed due to the differing load.
You already say you suspect the NS cv as an issue, I would not -a t this stage consider the ird a suspect.

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Changing the IRD oil instantly fixed it. Was reproducible - as soon as you took it up to the speed again it started making the din.

EDIT: Also the volume of shavings in the amount of time was silly, I'd expect that volume in years of use.

B34R said:

Changing the IRD oil instantly fixed it. Was reproducible - as soon as you took it up to the speed again it started making the din.

EDIT: Also the volume of shavings in the amount of time was silly, I'd expect that volume in years of use.

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Did the shavings look like steel or more brass-like? I seam to remember @Nodge68 saying something about the swarf on his IRD drain plug looking more like the shims rather than gears - maybe the oil you used was particularly abrasive to one part in particular.

GrumpyGel said:

Did the shavings look like steel or more brass-like? I seam to remember @Nodge68 saying something about the swarf on his IRD drain plug looking more like the shims rather than gears - maybe the oil you used was particularly abrasive to one part in particular.

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Was definitely dark material, I'll grab the oil brand when I get home tonight for people to have a look.
I was wondering if it was just dirt that had cleaned off - but it was stuck to the magnetic plug so I don't know.

Doesn't seem to be any worse for the wear though, no play at all in it and it's now silent as anything.

Hi B34R.
It sounds fairly illogical (don't get me wrong mate - I accept all that you are saying!)
When you say "Changing the IRD oil instantly fixed it. Was reproducible - as soon as you took it up to the speed again it started making the din."
What do you mean by reproducible ? did you try it with 10 W 40 and then drain that and refill with the old brand ? ?
If the particles are stuck to the plug they are steel. - not from the diff thrust 'cups'

I just find it incredibly hard to believe that an OIL has actually caused an issue unless the stuff you put in is really absolute pants from some back street chinky oil shop ?

I also cannot see how you can have a

B34R said:

godawful bearing noise started up from the gearbox area, completely invasive into the cabin and an awful din on the ears.

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that was in anyway immediately changed by changing the oil (presuming the original was of a reasonable quality and actually conformed more or less to the spec)
If a bearing was knackered, it would be still knackered even after the oil change. -
It is a chicken and egg also - IF the issue is the ird - then did the oil CAUSE the issue ? (highly unlikely with info we have so far) or did the IRD simply start to fail regardless of the oil - and the metallic particles were due to a non oil related failure.

I presume from what you say that you were running 2wd at the time ? - (this takes away a lot of stresses on certain parts of the IRD of course)
Check the DS driveshaft (on a UK car) where it enters the IRD as a worn cv joint here can cause fairly catastrophic failure of the Main IRD diff ouput / support bearing leading to a huge disruption of the quad gear diff drive meshing tolerances and extremely rapid were ! - this type of failure actually usually results in a cracked casing at the DS drive shaft ouput...

Definitely need to see the oil make and type - but I still honestly say that unless it really is something crappy - then I cannot see any connection. The only potential scenario that fits at this time is - as the diff is splash lubricated - that the ird 4 gear cluster to the diff actually is failing in pretty bad way ! (due to support bearing failure leading to the gear teeth rapidly eroding or chipping )- (probably nothing at all to do with the oil )- however - from the internal gear chain / diff / diff drive gear pair failure - particles get suspended in the oil and also some stick to the magnet. Draining the oil (and I presume you found other mess in the drained oil) removed the majority of the suspended particles. the particles in the bearings were possibly causing a horrible noise and by flushing and changing you effectively removed the contamination from the 'noisy' bearing. If this is the case, then it is only a matter of time before it happens again or more likely - catastrophic failure of the IRD.
Again whether it was down to oil or not is highly questionably. If it is the IRD - it may have simply had its day.
As you said " Also the volume of shavings in the amount of time was silly, I'd expect that volume in years of use." is not indicative of good times ahead.
Hope you get it sorted.
Joe

I can't see how changing oil can stop a noise, if it's that bad. My suspicion would be that the VCU has entered HUMP mode, overloading the IRD or rear diff.
This is what I'd expect to see on the plug magnet.

Nodge68 said:

I can't see how changing oil can stop a noise, if it's that bad. My suspicion would be that the VCU has entered HUMP mode, overloading the IRD or rear diff.
This is what I'd expect to see on the plug magnet. View attachment 104335

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Fully agreed nodge mate - however, I think the OP said he was already in 2ed vcu removed....
Joe

Joe_H said:

Fully agreed nodge mate - however, I think the OP said he was already in 2ed vcu removed....
Joe

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I missed that post Joe
I can't see how a horrible noise can miraculously disappear with an oil change. There must be more to this than the oil.

Nodge68 said:

I missed that post Joe
I can't see how a horrible noise can miraculously disappear with an oil change. There must be more to this than the oil.

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Again, 100% agreed mate.
Joe

I'm just calling it as I see it at the moment, it made a din, I swapped the oil, it stopped making a din.
No VCU to screw with it.

I suspect a bad oil batch where it's shear didn't come up to spec or something, after a couple of months the plug looked like the picture above.
Maybe I used the wrong expression "metal shavings" but it went clean to that in a very short period.

B34R said:

I'm just calling it as I see it at the moment, it made a din, I swapped the oil, it stopped making a din.
No VCU to screw with it.

I suspect a bad oil batch where it's shear didn't come up to spec or something, after a couple of months the plug looked like the picture above.
Maybe I used the wrong expression "metal shavings" but it went clean to that in a very short period.

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Hi Mate, you really need to quote and show us the oil you used - also - as said - oil is indeed unlikely to be the issue. Please check the DS driveshaft as well where it enters the IRD.
I honestly do not - until proven differently - suspect 'bad oil' at all. Or a 'bad batch' - if indeed you have - which I would be utterly gobsmacked - then send a sample back to the manufacturer for analysis. IF there was a real issue - they WOULD pay your costs as this would be a one in many millions chance.

As both Nodge and I have said - a noise as you describe could not in all reality be 'cured' by a change of oil when as you also said - the oil was of the correct quantity. It simply does not compute - for it to be that bad a 'noise' then a simple oil change would do nada. I think maybe you need to look elsewhere.
Again, best of luck.
Joe

Joe_H said:

Hi Mate, you really need to quote and show us the oil you used - also - as said - oil is indeed unlikely to be the issue. Please check the DS driveshaft as well where it enters the IRD.
I honestly do not - until proven differently - suspect 'bad oil' at all. Or a 'bad batch' - if indeed you have - which I would be utterly gobsmacked - then send a sample back to the manufacturer for analysis. IF there was a real issue - they WOULD pay your costs as this would be a one in many millions chance.

As both Nodge and I have said - a noise as you describe could not in all reality be 'cured' by a change of oil when as you also said - the oil was of the correct quantity. It simply does not compute - for it to be that bad a 'noise' then a simple oil change would do nada. I think maybe you need to look elsewhere.
Again, best of luck.
Joe

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There's nowt wrong with the drivers side one, it's rock solid.

The one with a tiny amount of play in it is the nearside one that goes into the gearbox.