I'm FI and putting a bit of power through my original diff but never abuse it. Well almost never. I have launched in anger a couple of times (broke an axle once).

I've recently got a new quieter exhaust. I am now atuned to all the sounds my car makes, including a bit of diff whine.

I've been running LE607 in the diff since and 37000Kms. Now at 71000Km I did a fluid change (to LE1605). In the diff drain plug I noticed some small metallic particles. Just a couple of match head sized fleck and some grains.

I haven't driven since the change (it's raining hard).

Anybody have an opinion on whether or not I should expect imminent diff failure?

 

It is a possibility that the diff may quiet down after the fluid change. But for all you know it could have been this noisy for quite a while and you just couldn't hear it over your exhaust. If I were you I wouldn't lose to much sleep over it just drive it and be careful. But if your paranoid you could always upgrade. S2kPuddyDad builds excellent diffs and I plan on upgrading eventually when I go FI but thats a couple years down the road. Either way good luck!

 

Cheers. I guess I won't know if the noise has gone until this rain stops

I'm familiar with Puddy's excellent work but freight to Australia is the problem. I've got a spare diff here and will have it built locally eventually.

 

I would shorten the OCI.
Some flakes and grains are not that bad, less is always better though.

You could turn the propshaft by hand CW and CCW (wheels off the ground) and watch for axial movement of the pinion when you change direction of the propshaft.
If you see that = bad!
If you dont and you can easily turn the propshaft both ways without feeling too much resistance and no change in resistance the ring & pinion are ok.
To confirm that inspect the ring through the drain hole.

It looks something like this.
Let the oil drain for a while!


Much like this Webber guy when he gets overtaken.. aye!

 

LOL, yeah us aussies are a tad impetuous at times.

Will jack the car up again and do the prop rotate test.

Oh, and what is OCI?

 

OCI = Oil Change Interval.
IOW the time or milage between oil changes....

Did you use the LE-607 for 34000 km?
That's a tribute to the oil, especially being FI.


Depending on what you find and how the diff sounds now I would change oil in 10k km.
An extra change only hurts the wallet.

 

I agree with Spitfire 100%.

Did you happen to save any LE 607 that you can do a used oil analysis on?

Also, even though LE 1605 is the replacement for LE 607 (discontinued), it is a totally different chemistry. LE says that it is compatible with LE 607, but I think a short OCI would be prudent for a complete exchange. That would maximize the benefits and effects of the new 1605 for your FI demands.

Isn't it wintertime down under? Gear whine should be at a minimum right now for you. But I really think the quieter exhaust will make you a hypochondriac now!

 

PM sent with information on a possible fix to your whine issue, good luck

 

So what's the secret?

 

Sorry, I've been sworn to secrecy. Secret handshake and all.