Very interesting read. I have been experiencing similar transmission issues for some time though not as frequently.
If I give it too much throttle it will slip out of the gear, not sure of which and going into F limp mode with what I suspect is 3rd selected and high RPM. Lock / unlock 3 times clears it and off I go again.
Similarly if I give it too much going up a hill or use cruise control it will try to down shift, doesn't like something and jump back to the high gear then go into limp mode with again 3rd selected.
If I use light throttle around 2k it will behave. I have had TC shudder about 5 years ago and did a tripple flush, new valve body seals, filter and some Dr tran and it settle it down for a long time though it would still present slipping.
I do not get the HPFP codes the OP was getting.
I did a trip Hervey Bay to Gold coast and back with only one fail event and that was me getting cocky going up a hill with too much throttle applied.
I am starting to feel slight what I expect are TC shudders and small deviations in RPM in alignment with said shudders, not major though.
I do get slippage in middle gears, think 3rd is worst but also 4th.
Most of the U codes are cascading CANBUS faults. Below is the fault from recent trip to Gold Coast and back ~ 9 hour round trip.
L319 - Discovery 3 2008
Vehicle scanned on 20-05-2024 15:10
Using IIDTool BT V3.0 B2742
Engine TDV6
- U0416-00 (28) Invalid data received from vehicle dynamics control module
Instrument Pack
- U0132-87 (28) Lost communication with ride level control module - Bus signal/message failure - missing a message
Terrain Response
- U0402-94 (20) Invalid data received from transmission control module - Component failure - unexpected operation
( on 11-05-2024 15:08:22 at 355152 km )
Transmission
- P0730-00 (60) Incorrect gear ratio
( on 11-05-2024 15:04:04 at 355146 km )- P0735-00 (60) Gear 5 incorrect ratio
( on 11-05-2024 15:08:21 at 355152 km )
The vehicle was a bit sluggish and at last service before doing the GC trip I cleaned both MAF & MAP sensors which seemed to improve things.
I also tightened the top and bottom clamps on the top intercooler hose as I had a bit of an oil film over the blue silicon intercooler hose though could not find any splits, no hissing and no black smoke under load.
I am thinking the ZF will need a full rebuild inc TC & valve body. It has about 355k on it. My LR indie is making some enquiries on getting it done, send to Sunny coast auto trans rebuilder or down to ZF in Sydney.
Neither is a cheap option.
Hopefully I do not get the dreaded HPFP issue others have had.
cheers
Peter

