Lock Up Clutch Logic

[swathdiver]

Here's what happens and my question is, is it normal?

Slow acceleration from a stop to 40 mph the converter will not lock up in 5th or 6th and continues to slip, the command to lockup says NO. Once speed is reached and cruise control set, stays unlocked.

Quicker acceleration from a stop to 40 mph, the converter gets the command and locks up in 5th and 6th and stays that way after the cruise is set.

Watched this about 4 times and at various speeds, accelerating onto the highway she'll go into lockup for example.

Second question: Any reason or logic why?

Transmission tuned in person by Justin about 3 years ago. @BlackBearPerf

 

[exp500]

Maybe it;s part of the learned behavior? You must be way gentler on the go pedal than you normally are! Seriously, isn't the drive cycle about 50 miles?

 

[swathdiver]

Maybe it;s part of the learned behavior? You must be way gentler on the go pedal than you normally are! Seriously, isn't the drive cycle about 50 miles?

Drive cycle?

 

[BlackBearPerf]

Here's what happens and my question is, is it normal?

Slow acceleration from a stop to 40 mph the converter will not lock up in 5th or 6th and continues to slip, the command to lockup says NO. Once speed is reached and cruise control set, stays unlocked.

Quicker acceleration from a stop to 40 mph, the converter gets the command and locks up in 5th and 6th and stays that way after the cruise is set.

Watched this about 4 times and at various speeds, accelerating onto the highway she'll go into lockup for example.

Second question: Any reason or logic why?

Transmission tuned in person by Justin about 3 years ago. @BlackBearPerf

This is from Justin, "Very strange. Random Misfire codes present by any chance?"

 

[swathdiver]

This is from Justin, "Very strange. Random Misfire codes present by any chance?"

Not present and never had any misfire codes.

 

[Tonyrodz]

This is from Justin, "Very strange. Random Misfire codes present by any chance?"

Misfire codes affect the trans, tc lockup?

 

[BlackBearPerf]

Not present and never had any misfire codes.

Justin thinks its very strange, and said he would need to see a log file, if possible, to really see what's going on.

 

[swathdiver]

Justin thinks its very strange, and said he would need to see a log file, if possible, to really see what's going on.

Ok, At next opportunity I'll break out the AutoCal and and send him a data log. Thanks.

 

[swathdiver]

Maybe I crossed my thoughts but tonight it was accelerating very slowly that got the converter to lock up between 35 and 50 in 5th or 5th gear. Sometimes it would lock up in 5th but unlocked in 6th at those speeds.

If the acceleration was normal or brisk, it did not lock up at all. But did lock up above 55 mph in 5th and 6th. No misfires whatsoever. I did notice that the LTFTs were often a bit high, especially while idling, but the motor has always been this way. Throttle plate at idle was 7% to 9% and at other times I've seen 11%. Still no DTCs.

Next time out I'll hook up the AutoCal.

 

[swathdiver]

Apparently this has been going on for some time, didn't notice it when I took this data log via Tech-2 Snapshot in August of 2019.