How often on a modern car does one change trans and diff oil

[cib24]

I was wondering how often people are changing transmission and differential oils on their modern cars (let’s call that post-2012?).

I was looking at my Range Rover service intervals as recommended by them since my 4 year service is coming up and it looks like the following aren’t supposed to be replaced until 105,000 miles / 10 years:

Transmission oil and filter
Transfer box oil
Front differential oil
Rear differential oil
Coolant

That seems like a long time but perhaps the modern ZF 8 speed and the differentials can take such a long interval and work without issue? I know of some BMW boxes being sealed for life as opposed to having a change interval like JLR.

Are your modern cars similar with a decade between transmission and differential services?

Edited by cib24 on Friday 18th August 13:19

[Lincsls1]

I'd be ignoring the schedule and changing the whole lot on its 5th year service
I guess it depends on whether you consider the car a keeper, in which the extra maintenance is preferable. If you're moving thr car on in a year or 2 then just stick to the standard.
From what I understand, there are plenty of enthusiast BMW owners that rightly IMO, ignore the sealed for life and get their boxes serviced.

[cootuk]

2018 Forester, just changed diff and CVT fluid at 4 years) 80,000 miles .
With CVT fluid cost depends if it has an internal magnetic filter and you drop the pan to clean that as well, or just drain so many litres of fluid and top up.

[dxg]

On my mx5, it's every five years / 60,000 miles. Just had it done. Even though the car have only done 13.5k...

[vikingaero]

3 year lease car, or only keeping the car for a few years - never.

Keeper - halve recommended intervals.

[trickywoo]

5 years makes sense to me. Even sat in the container oil has a shelf life around that time.

While box oil doesn’t get exposed to combustion byproducts it also doesn’t tend to have a filter and is subject to heat cycles. 10 years is way to long.

[healeyneil]

2006 Z4. Both the gearbox and diff are “ sealed for life “ with no drain plug. I drained both with a giant syringe ( at 85000) and replaced. The oil that came out was nice and clean !

[kambites]

It's quite common for the gearbox and diff to be non-service items these days. Whether it's a good idea or not I don't know, but the scrapyards don't appear to be full of cars with seized gearboxes or diffs so I suppose it's OK.

I get the feeling a lot of people (including myself!) perform unnecessary service actions because 20 years ago they were necessary. Replacing it regularly can't really do any harm!

Edited by kambites on Friday 18th August 08:00

[trickywoo]

healeyneil said:

2006 Z4. Both the gearbox and diff are “ sealed for life “ with no drain plug. I drained both with a giant syringe ( at 85000) and replaced. The oil that came out was nice and clean !

I don’t doubt the colour was ok but I bet if you looked at the drain pan in the sun it would be glittery.

[JWH]

I generally ignore the manufacture recommendations and change those fluids on cars I intend to retain for the long term but I'm rather unsure of how necessary it really is. My previous daily driver, a manual E91 330d was sold on at 240k miles (owned by me from 55k) having never had a gearbox or diff oil change and was showing no ill effects at all from that.

[AC43]

I do the boxes on Mercs at 5 year or 50k intervals.

[Earthdweller]

trickywoo said:

healeyneil said:

2006 Z4. Both the gearbox and diff are “ sealed for life “ with no drain plug. I drained both with a giant syringe ( at 85000) and replaced. The oil that came out was nice and clean !

I don’t doubt the colour was ok but I bet if you looked at the drain pan in the sun it would be glittery.

Did both on my Zed last year at around 60k miles and 16 years ( I had no record of it ever being changed)

The diff oil looked like new but there was a definite difference in the gearbox oil between what came out and what went in. There was a noticeable difference in the quality of the change afterwards

This is the oil that came out the gearbox

Edited by Earthdweller on Friday 18th August 08:24

Edited by Earthdweller on Friday 18th August 08:26

[Pica-Pica]

I can’t remember ever changing oil on a manual transmission nor on a differential. That is going back to the 1970s, I kept my cars for at least 150k miles and 10 years from new (longest a E36 for 19 years). Most cars rusted away. I have a ZF8 auto now, so I read all the ‘sealed-for-life’/‘must change at 80k’ discussions, and will probably have that changed in its time.

[Cambs_Stuart]

I've not had a sealed for life gearbox, but every time I've changed the fluid in a gearbox there has been a noticable improvement in changes and general operation. In my clio I change it every 2 years, at the last change the fluid that came out was really clean. Renaultsport gearboxes are notoriously weak so I'd rather spend £60 on fluid every 2 years than £800 on a rebuild.

[ninjag]

Fluids, even the fancy DSG stuff, isn't particularly expensive compared to what they help protect so for me (plenty of spirited driving but no track use) this is what I go with:

ZF 8HP 70 at approx. 60-70k miles including integrated sump/filter.

or

DL501 0B5 every 40k miles including external filter
+ DSG transmission gearbox (which includes front and centre diff), at 70k miles

Standard Rear diff at 70k miles (LSD could be sooner)
Coolant; when it shows it no longer works properly
Brake Fluid every 2-3 years
Engine Oil and filter every 6 months/5k miles

[Smint]

If your RR has covered under 50k i'd get the lot done next year when its 5, unless its more convenient and/or the mileage is over 50k in which case maybe consider getting it all done this time.

I give all that sealed for life cobblers a good ignoring, like others almost every gearbox oil change i've done has resulted in an improved drive.

[gotoPzero]

On a range rover get a proper power flush company out to do the gearbox and do it at your house.
There are a few good ones who do a lot of Range Rovers so will be able to do it in a couple of hours start to end and will be a 99% change.

The rest of it I would DIY as fairly easy to do yourself. Few good videos on youtube and the fluids required are cheap. Get a decent fluid extractor and it will make the job so much easier too.

As for intervals I would do all fluids every 4-5 years on a RR. They are big heavy vehicles and the transmission / drive line is actually taking quite a bit of stick just driving around normally let alone towing or off road.