Glad you got to the bottom of this issue!

I never saw this thread until today, I also know RRPhil's knowledge of automatic transmissions is legendary.

But, if anyone else gets issues like this after a fluid change, the first thing I'd recommend is to have the transmission fluid changed again... just in case the wrong stuff had incorrectly been put in!

Especially as the issue came up after a period of time running, so seemingly fluid temperature related which could indicate the incorrect viscosity oil had been put into the gearbox.

I'm not suggesting this is the case in your example, but it's cheap enough to do, so worth doing just to see if it WAS incorrect transmission fluid causing the issue.

I'd also check that the adaptions had been reset following the fluid change.

Too little, too late in your case (on my behalf), but might help anyone else looking at this thread in the future!

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
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Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

All great advice Jon.

And like you, I didn't question RRPhil's knowledge. It's just that even he couldn't put his finger on the precise cause though his first thought was a solenoid. I could have done another fluid change and if that didn't work, I could have done the solenoids. But if that didn't work I'd have to do what I actually did. Ultimately I took the cost on the chin and did the lot in one go. Even then, it wasn't a guaranteed fix so I'm thankful it worked.

One point you make is about re-setting the gearbox adaptations. That wasn't done after the fluid change last year but was done after the refurb work. It might be a debate all on its own because I didn't think it advisable to do the adaptations reset after a fluid change. I'd be interested to hear others' thoughts. Des

2005 (2006 MY) L322 4.2sc Java Black, 2010 facelift conversion
1965 Lenham Lemans GT 1310 , Gulf Racing blue, FIA spec and road legal
2018 F56 Mini JCW, Thunder Grey/Black, Mulgari St2 tuned, FMIC, short shifter and Eibach springs