Quick update with what's been going on with my car, which is a 2016 L405 SDV8 on approx 90,000 miles
Engine has recently started to give the impression that it is revving a bit more than usual in lower gears.
Had the new sump kit and fresh oil fitted two weeks ago but it did not have a full flush through.
Technician said the old oil was very dark but there was very little sludge in the sump, nor metal shavings on the magnet.
Still seems to be revving more than usual but there is a slight improvement since the service.
I do find that sometimes if I lift off the throttle a little the auto box will change up a bit faster.
Yesterday, I was driving normally and the transmission suddenly selected hill descent mode.
No matter what I did with the settings, it would not revert to standard mode.
Parked the car and went into a meeting and when I came out, all seemed to be back to normal.
I have an iCarsoft LR V2.0 diagnostic kit but not too familiar with it to feel confident to use.
Anyone had this happen to them? All help or previous experience of this would be appreciated.

Gearboxes learn and self adapt their bite points for the clutches, and will do so to deal with the oil as it changes over time and wears. So new oil will behave differently from the old oil, but the box it still set for old oil. You can generally reset a ZF box by:

Ignition off.
Foot full on throttle, including kick down.
IGN on ( no foot on brake! )
Wait at least 30s … i normally wait a minute.
IGN off.
Foot off throttle
Leave it to sit for a bit.

That normally resets the box to its default state, and it’ll learn the best bite points and clutch pressures again.

As far as I know, the box will learn its adaptations under certain acceleration / deceleration conditions. And if i remember correctly, they are along the lines of as below. If you have a long flat-ish section of road that’s quiet, then that’s best.

From stand still:
Accelerate gently and steadily not going above 2500rpm ( so raise it to just under 2000rpm and hold it there whilst it accelerates)
Let it get up through the gears to 50mph ( in the old 6 spd in the L322, this would equate to getting into 4th gear … but the 8spd will be a different gear )
Hold 50 for a short period
Foot off the throttle and let it decelerate down through the gears as it wants to until you are about 10mph.
Then gentle brake to a stop and pause, or drive along for a few seconds / turn around and repeat the process.

I think the docs I read said about 3 or 5 times would get the adaptions set.

These conditions make for steady acceleration / deceleration which the gearbox can learn to bite and let go the clutches smoothly.

For me, there are a couple of junctions that I pull out of regularly, and they naturally allow for the process to happen … and I think it does keep things in smooth. V8 or else ...

Thanks for that advice. I shall give a go tomorrow.
That's if I can find a section of road that lets me "play"

It is recommended that the oil be changed at 50k miles so your box should be coming up for its second oil change and will be overdue if it has never had one. So, I'd get the oil changed before doing an adaptive reset as new oil may make an improvement int he box feel.

I did an oil change on my ZF 8sp after 50k miles and never bothered with a reset as it is running silky smooth.

Thanks for the reply baz000000.
As per my original post, I have already had an oil and sump kit change done.
I will try the reset procedure later today (once "family matters" are sorted )
What I still can't understand is why the gearbox suddenly selected Down Hill Descent mode in the Terrain settings? Fortunately for me, that seems to have settled down and it did not occur during driving yesterday.

There are a lot on here who do not reset adaptions, it is thought that this could do more harm than good and like telling the Range Rover it has a new battery, there is no reason to do it as it will learn that the gearbox and/or battery have changed in normal driving...

I'd just give it a few hundred miles and see what happens...

If you just want to drop and fill then do a few more oil changes to change a larger % of the oil... No need for a new sump, just a few oil changes....  Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Do you use the flappy paddles to change up/ down. These can sometimes cause the gearbox to reprogramme itself to reflect your driving style. 2012 tdv8 Westminster arrived Jan 19 gone Dec 23

200 TDi discovery bobtail gone
RR classic v8 bobtail gone
300 tdi Discovery 3 dr gone

V8bob,

just off now to take a short run and use the paddles through all the gears.

I'll then try the reset as previously suggested.

The gearbox constantly self-adapts anyway, so over time it will adapt to the new fluid anyway. No harm in doing a reset though. Kev

2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey