Changing Differential Oil

[Mike Floutier]

Hi all,

I've just bought a lovely 2002 LS 430 with 143,000 miles on the clock and I'm just drawing up a maintainance schedule as I would like to do most of the work myself.

One thing I find a little surprising is that they recommend changing the Differential oil every 20,000 miles. Now in my job this means at least 3 times a year and I'm wondering if such a frequency is really necessary and WHY?

I'm running an 11 year old Ford Scorpio at the moment with 313,000 miles on the clock. The diff oil has never been changed until recently and there have been no problems.

Can anyone throw any light on this?

Also, in the workshop manual I can't see any details of how to drain and refill the oil - it simply says to do it.

Thanks

Mike

[ColinBarber]

Are you sure it isn't just an inspection every 20k miles to check the level?

I would probably change it every 60k or 100k miles.

I doubt there is a drain, you need to suck out the oil from the filer.

[GoldfingerLS]

I've had the diff oil changed before on my LS400. There is a drain bolt and a refill bolt. You will need a new washer for each one, i can't rember if the washers are re-useable or if they were the collapsable type.

Changing the diff oil will get rid of any metal shavings in the diff.

[Mike Floutier]

Check this 4 down on the right. It's pretty clear, I'm just wondering why it's recommended. I'll do it if I have to but every 20k?

Mike

[GoldfingerLS]

On the service book for my mk4 ls400, it says replace every 27,000 miles. You can probably get away with doing it twice a year in your case maybe ? The diff takes 2 litres of fluid which should cost about £10 so not a lot of extra cost, and you can do it at the same time as you change the fuel filter (its near the rear diff on my ls400, not sure if its at the same place on the ls430).

Not sure what would happen if you didnt change it that regularly.

[Mike Floutier]

On the service book for my mk4 ls400, it says replace every 27,000 miles. You can probably get away with doing it twice a year in your case maybe ? The diff takes 2 litres of fluid which should cost about £10 so not a lot of extra cost, and you can do it at the same time as you change the fuel filter (its near the rear diff on my ls400, not sure if its at the same place on the ls430).

Not sure what would happen if you didnt change it that regularly.

Thanks Guys,

I think I'm going to try doing it at 20k and see how easy it is. The workshop manual shows a drain plug so I guess it can't be too bad. I'll probably find that it takes 10 minutes, costs next to nothing (as you said Goldfinger) so I'll be more than happy to do it - hehe!

I suppose the reason I'm trying to avoid it is because the one time I ever did it on my Scorpio I had to syphon it out and it took about 8 hours and still didn't get it all out. Then, when I changed the diff. itself, cos I thought the noise I was getting was coming from it, the new one sounded exactly the same, proving that 300k with no oil change didn't bother it in the least.

Oh well!

Thanks!

Mike

[cardona6569]

The Manual asks to change it if you use your car hard, like 99% of drivers. I would not be bothered with changing it every 20 miles as long as you use Synthetic Fluid such as Amsoil or Mobil, if you use Amsoil you could even go to every 30,000 miles and they even say 50,000 miles. If you use Mobil you could do 20,000, but if you use mineral based oil I would stick with the factory prescribed of 15,000-20,000 miles. You do not want a breakdown that could run you into 1000's of Dollars, Euros or Pounds, etc. CPF