Phew. I was a little nervous that I used the wrong fluid.

The valvolene high milage ATF with a bottle lucas tranny conditioner has created a nice smooth tranny. 3 changes over 500 miles allowed me to have pretty much fresh fluid all thru.

 

Just to follow up on this...

I took the disco back to the shop and they reset the transmission computer and now everything is back to running smooth as glass; I can barely even feel it upshift between 3rd and 4th now.

The mechanic had said that the bands and clutches in and old transmission don't always play nice with new fluid. Reseting the transmission computer allows it to relearn how to operate with fresh fluid.

 

How do you reset the transmission computer?

 

@ebg. I flushed mine similarly. I changed the fluid and drove it, then changed again. I did this 4 times to make sure it got into all the nooks and crannies and drained out any crud that had built up then broke loose. The last change I put in a bottle of Lucas, and so far it's been great.

 

You don't/can't with the exception of the adaptive memory, why do you ask, do you have codes, if so what are the fault code numbers?

 

Yikes guys,
That means I am in for trouble.
I just drained the pan - which is 2.5 oil bottles ( 1/2 quarts?)

Then drove around.
And, then drained 2.5 more transmission bottles worth ( 1/2 quarts)?

Before I started this I noticed a slight shudder when starting off from a stop.
I notice that shudder is there when the truck is really hot.

After changing the fluid to Mike's specification of the Valvoline Extended over 75,000 miles stuff and adding the Lukas - I still get the slip.

So, I figure I'll be in Transmission rebuild heaven soon enough.
4HP22EH here I come.

You may benefit from adding that Lukas Transmission fix stuff right into your trans.
It is a bear to get in there as it is really thick.

from what I read.
the transmission will via the CAN buss send a command to the ECM to
reduce engine output during shifts.
That may be the lag you are feeling.

Thinking a rough shift - like a whack or a slam-
the transmission controller computer tells a shift solenoid to
activate.
This changes the fluid pressure to a clutch or clutches.
if the clutch grips really suddenly - then this could make a rough shift.
The clutch is all plates and the fluid in the transmission will determine how
"grabby" the clutch plates are.

 

So, one more idea.
Since you put in new fluid - had a flush- the friction modifiers in the fluid have been upgraded.

The transmission computer is still shifting as per the old fluid - which had no friction modifiers as they were all worn out.

So, the computer is shifting it hard as it used to slip a little.
Now with new fluid - the clutches grip well.
And, that is your hard shifting.

Somehow the transmission computer has to be put on reset so that it learns from
what it has now.

I would think it will relearn over many miles but you will need to suffer hard shifting while it does.

People are saying battery off for 15 minutes resets the TCM.
On Rovers' who knows?

I bet Savanna knows..

 

So, in doing a change in the transmission fluid it is be expected the truck will shift hard and need potential programming? Is this a normal thing to experience.
Here I was thinking, drain the old, add the new and be done. Am I missing something?

 

re: reset adaptive tranny ECU memory

From RAVE, it would appear these memory conditions are stored in volatile (vs non-volatile) memory, so battery disconnect and key on position 2 and brake lights pressed to discharge capacitors, and leave for 1/2 hour might do it.

I am also a big believer in this: Dr. Tranny Instant Shudder Fixx , O'Reilly and other places stock it, as do a lot of tranny shops. It is a synthetic version of the very fine oil produced from the sperm whale, chemically a very long molecule. Also quiets tranny's. A companion product is available for transfer cases. Despite low brow humor, no, it was not whale sperm.

 

You asked a question, I replied and you have not answered my question so I can help you, was your question just a waste of our time.