Hi i was reading an article in the technical section about changing your diff oil bang up job by the way very well written for us dumb minded ppl. It just came into my head about how do u know when to do this is there any signs time periods that this should be done because im sure it doesnt get done with your service's. So yeah any idea would be great ive had my calais now for 1 1/2 years and never thought about it does it give as much benifit to your driving as changing your engine oil? cheers guys Also just like to say these forums rock its great for us to be actually able to read get info and ask questions well done!!

Diff oil doesn't need periodic changing. If you have the diff out of the car, then go ahead and change it. Other than that, I'd say you should only need to drain/inspect/change the oil if the diff is making weird noises.

You could say that by the time its making funny noises, something has already gone wrong. When i wrote that article, the only reason i was doing it was as a preventative measure, as i guessed that it hadnt been changed in ages. I was right! It would have probably kept on going for longer, and it wasn't playing up, but i wanted the peace of mind in knowing that an expensive piece of hardware had fresh clean oil, and a nicely sealed gasket. in other words, do it once (especially if you think it hasnt been done in a while) do it well and then forget about it! ezy. Creeper Some original photos have not been recovered yet.

As I've said previously about this topic " if it ain't broke don't fix it" Changing diff oil is going beyond preventative maintenance. Are we going to change power steer fluid and clutch fluid as well? And rebuild our alternator and starter motor 'just in case'? Real preventative maintenance for diffs should include checking oil level only and not flogging the guts out of your car: burnouts

pull the plug off and get in close and smell it, if it smells bad you dont need to change it. it loses it stench when it is no good

I hear what your'e saying 880, and i do agree with you in part. Checking your diff oil is always a great thing to do, because a diff with poor/no oil isnt going to be too happy. *But* when the history of the car is questionable (as was the case for myself and it looks like VL2GO too) it DOESN'T HURT to change the oil in the diff - your'e eliminating one more possible source of failure that could be very costly in the long run... and for the sake of an hour of your time and $20 its a fairly small price to pay for peace of mind. if you want to change it go for it you certainly wont hurt the car (unless you REALLY **** up ) creeper Some original photos have not been recovered yet.