Have many things fixed and road testing now.
Generally transmission feels good, but noted going about 60km/hr it upshifts to what I think is 4th, then drops back, and upshifts again, drops back (this is when you are on the verge of suitable speed for 4th).
I haven't driven it faster than this yet.
I'm going to test more to clarify this, thought I'd throw this out for discussion...
P

 

What car?

 

Maybe it is a JAGUAR?????????????

 

The OP lists 5 cars but none looks to be a Jaguar...

 

This is the STR forum correct.... 2003 S-Type R
I'm trying to drive and get more data, but it is similar to maybe the Torque converter locking and releasing - but I have to confirm my gear / speeds

 

The MY / VIN matters for some of the issues. For a 2003 maybe that's the known TC issue.

 

Was any of this recent work on the transmission?

Not overly familiar with the late models, but isn’t there a self-learning process with the transmission? If it had some recent work, you may need to log some miles and cycles for everything to settle in.

If this is the case, and the car does need to be driven until it can relearn, I’d suggest minimizing time when the transmission is hunting. When you drive above that range, accelerate through the problem zone quickly.

 

The work done is not transmission related.
M64848 is the chassis number.
wondering if a passenger can monitor transmission functions - gear number and TC clutch position? Using IDS? This would really be helpful.
it looks to me that the transmission pan has been down/changed at some point based on the hardware- but really not known.
i need less traffic and more space to better road test and observe.
my initial thoughts are that it does really sound and feel like the TC locking and releasing, not yet sure if I can “drive through” it to a stable higher speed…..

 

That's in the VIN range for such as S307-10 & S307-14 but it may not be either of those.