JayGee wrote:

ZF8HP gearbox issues on these cars are very rare. A normal service just involves dropping the oil and replacing the pan / filter and does not include changing internal sleeves.

cass wrote:

I'd be tempted to go with your idea of checking the level before looking for other problems. It is VERY easy to get the level wrong - I changed my oil, thinking that the car was level, oil temp was correct and I had cycled the gears.
It drove OK, changes weren't as smooth as before which I put down to it adapting to the new oil. This got worse over a couple of days, showing all sorts of random misbehaviour.
Checked my level carefully, my car wasn't level on my hoist when I checked with a spirit level, tweaked this then used the exact gearchange sequence specified by ZF and got more than a litre of extra fluid in.
Everything back to normal.
It's got to be worth a try

GraemeS wrote:

Ffrr-lover wrote:

What am I looking for when doing this? I expect it to continue to rev as it does now… but will check when she’s back on the road.

You would be looking for positive gear changes without TC slip, just like a manual except that the clutch is automatic. With the right amount of throttle, by around 1700 rpm the torque should have tapered off enough to allow the gearbox to not decide to slip the TC on take-up of the clutches for the next gear.
The change to 3rd will see the revs come back a long way as the gap to 3rd from 2nd is too great on this early version of the 8-speed, so don't apply too much throttle until the TC is locked unless you've taken the revs higher.

This exercise requires that the take-off starts in command/manual mode 1st gear, either drive or sport mode. I always use this method when towing my 2.5T van when taking-off to keep the TC locked.

I’ll give that a go… I just need to replace my front struts first (leaky airbag) and then can try it out.  Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

So struts changed, and while out making sure all was well, I tried your suggestion GraemeS.

Bring gentile with the throttle, and using the paddles to change, the gear changes are seemingly good. I change to first, pull away and change to second at around 1700 rpm, and the subsequent gear changes are good.
However, I have found that I can replicate this if I am light on the throttle, back off the throttle for the gear change and then reapply the throttle only when the gear is properly engaged.

In addition, with the paddles, if I leave it in too low a gear when slowing for a corner (say third), then the revs flair as if riding the clutch. I’ve not driven much to say for sure, but it seems that if in gear slowing to around 1,000 revs is fine, any lower and that’s when the “slipping” occurs…

Does any of the above give suggestions as to where the issue is? Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

Oh, and I’ve been quoted £2,200 for a gearbox “rebuild”  Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

It sounds as though yours isn't working any differently to mine was prior to my very recent EGR delete remap. The box programming slips the TC in 3rd if revs get too low rather than drop to 2nd. If gentle and left a couple seconds after releasing brakes before touching the accelerator then mine would keep the TC locked in 3rd down to around 1000 rpm but it was very reluctant to drop to 2nd without virtually stopping and would always unlock the TC first.

Now I can be more aggressive with the throttle at 1000 rpm in 3rd without the TC unlocking and no longer have to wait a while after releasing brakes to avoid the TC unlocking. I assume this is because the engine torque now exceeds the gearbox's programmed minimum torque before unlocking the TC, as the engine is more spritely, no longer floundering getting past being swamped with low oxygen exhaust gas.

Edit: My upshift paddle switch will now last a lot longer as upshifts occur much sooner, at revs not much different to when I previously would manually upshift. 2nd gear hangs on long enough to be useful instead of changing to 3rd when barely moving then changes to 3rd with the TC locking as soon as the gear change has occurred.

Thank you for the advice so far GraemeS. With you advice on checking in manual mode, I’ve found a sweet spot with the accelerator, easing off for it to fully engage the gear before reapplying power.
This, when I get it right, minimises the slip when at low speeds & revs.

It’s not a fix by any stretch… but lessens the frustrations it’s causing me  Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

Hopefully you find the sweet spot often enough and can just ignore it when it isn't behaving to your liking.

Ffrr, did you get a resolution to this problem. Mine is doing similar things. Thanks Kev.

Hi Kevin,
No improvement here at all. I have re-checked fluid levels, as well as flashed both ECU and TCU to latest versions with no real improvement.
At the moment I try to drive in such a way as to minimise the issues. Generally being very gentle on the throttle helps.

I have called a ZF specialist and am booked to have them diagnose the issue (as best they can do without stripping the gearbox) but my descriptions suggest a service is needed, with all perishable rubbery bits replaced. That is about £2k, however there is a possibility it could be more once they get eyes on the internals and perform pressure tests etc.

Sonnax supply a set of replacement seals kit for the ZF8 gearbox (ZipKit) and I am considering the option of doing those seals myself. It's easy to argue against doing it yourself given its a critical part of the car... but £2k plus is a lot of money!

My car had a faulty valve so there is a good chance my gearbox was running too hot for too long causing these issues. If you have a suitable tool (e.g. IIDTool) then it may be worth checking your gearbox temps after a normal run. I cannot remember what is classed as too hot, but recall mine sitting at over 120 degrees. Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

Oh, and good luck with yours!

Do keep us posted on what you do or find... Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

Bare with me on this one, but try disconnecting your battery for about an hour and let me know if you think things have improved.

I have the same issue, specifically second gear (worst when cold but still does it when warmed up) it slips and doesn't want to go into third easily and the revs fluctuate..seems fine once it's in third. Appears to be getting worse. A filter/fluid change did nothing.

I'm willing to bite the bullet and replace the solenoids and seals but struggling to find any part numbers any seals. Anyone got anything I can refer to?
Lots documented on the ZF6, not much on the ZF8.

Thanks

Sorry, been off the forum for a while due to a change of job...

I still have the issue. Not done anything with it except get frustrated...

I'm curious how you get on with the solenoid and seals. Its something I had considered before...
There is the Sonnax Zip Kit for the seals, and I have found solenoids on eBay... but you are right there isn't much information on these 8 speeds.

My only concern with doing "just" those parts is with the clutch plates. If we are slipping into and out of 2nd, then do we have excessive wear on those plates? I'd hate to go through all that to find the problems are still there...

Please keep us posted on what you decide to do. Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html