E86 Gearbox & Differential Oil Change Intervals

[Kevbuts]

Hi All,

I have just bought a 2007 E86 3.0si Z4 Coupe with 48k miles on the clock. I am a bit anal about looking after my cars, and therefore have been considering getting the gearbox and differential oils changed for peace of mind.

What are the recommended intervals for oil changes on the gearbox and diff?

More importantly, is this considered money well spent, or unnecessary at this mileage?

Also, what's the life expectancy of the water pumps on the 3.0si engines? I understand they can fail around the 70k mile mark, and have been thinking of changing mine for peace of minds sake as well.

Any help and advice that can be offered would be most appreciated.

All the best,

 

[Buckz]

box/diff are "lifetime" fluids but I'd go against bmw and say change it, I'm getting mine done at the next service. Won't hurt.

Pumps are random, some fail early 50-60k others last way past 100k+ it is literally unknown when it'll fail as there's no sign of it.

Often they fail completely or start failing, aka not running sometimes and running fine the other times you start the car.

mine is on 64k and I am not planning to change the pump until it fails.

 

[kis]

I have just bought a 2007 E86 3.0si Z4 Coupe with 48k miles on the clock. I am a bit anal about looking after my cars, and therefore have been considering getting the gearbox and differential oils changed for peace of mind.

Supposed to be a lifetime... but around the decade mark +/- a few years is what I've seen done before. I noticed a difference in mine and like you said it gives you peace of mind knowing its all fresh.

Pump? It's like rear springs. Some fail quicker than others. I'd probably er on the side of caution and get it done, or at least have it lined up for doing in the near future?

 

[Kevbuts]

Thanks for your thoughts and advice guys. Most appreciated. You've both confirmed my thoughts

I will get both the gearbox and diff oils changed, and the water pump scheduled for replacement soon.

Cheers

 

[mmm-five]

On my M, I was changing both every year as part of an annual inspection 2...but I was doing 25k a year back then.

I’ll probably still stick to the annual inspection 2 as it does no harm and is only another £100 or so on top of an inspection 1 at a specialist, and gives me new spark plugs & air filter.

 

[GuidoK]

TBH if you have money to spent I'd rather change the front control arm bushings out of precaution.
Those are imho the parts that age the quickest.

 

[Steve84N]

Gearbox oil is definitely worth changing, less so on the differential but it's not much extra.

 

[patriot66]

I changed the gearbox and differential oil in my Zed back in April. Much quieter car and smoother changes after. Well worth it. Having seen the state of the oil that came out of both, from now on I shall be changing it every couple of years. 'Lifetime' ? Utter nonsense ! :thumbsdown:

 

[Scooba_Steve]

I run box to approx 30k/5y and diff to 60k, though now I have the LSD I'm not sure it will need another change.

 

[Anonymous]

Do them all at same time won't hurt nor kill you just buy OE oils and I used millers for my box and oe for diff and engine and swapped out all the plugs

Find it made such a difference to mine Ill do it every 3 years now amd engine every 3/4k