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Discussion Starter #1
Well the car had been shifting at 5000 rpm for the 1-2 for over a year, now all of a sudden its around 4600-4700. I was half a quart low on fluid so I added that, still the same. I am gonna change the tranny fluid next week as it has almost 10K miles on it. The shift is controlled electronically so I am extremely confused here. The transmission has 130K on it.
 

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the shift is commanded electronically but the actual shifting is hydralic. at say, 4400rpms is when the EEC tells the trans to shift. it takes until 5000rpms for the trans to fill the accumulator, so it can complete the shift.

If your car is slower for some reason (added weight, taller gears, etc) that would explain it. Also if you did the J-mod that would explain it too since the J-mod makes the shift happen faster.
 

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Discussion Starter #3
I understand everything you said, but the car was running fine for all this time. Just recently (past 2 days) did the shift point get lowered.
 

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my car did the same thing. one day it shifted at about 5200 an about 50mph now its like 4500 at 35-40 mph
 

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Discussion Starter #5
thats exactly my problem, I hope a dyno tune can correct for this, if not I might have to make a grave for this transmission as the miles are climbing on it.
 

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Every JMOD I did caused the same thing. The accums fill quicker. if your trans was shifting later before, it actually could have had a slight problem filling, or exhausting.

Like Greenbird said, the ECU anticipates the shift, gives the command, and by the time it happens, a few hundred rpms have passed. In your case, about 600 rpms used to pass. Now it is simply responding to the command faster.

BTW, since the ECU gives the command, and that is usually triggered by the TPS (right?-I mean, the ECU needs to know your throttle position before it gives the command, so it knows if you are crusing, or WOT), perhaps the TPS is off somehow? Just a thought...

Try disconnecting the battery for 30 minutes or so, then taking it back out for a re-learn drive. Give it a few WOT shifts, and a few 3/4 throttle shifts. Only a suggestion. I have no reference to back it up.
 

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Discussion Starter #7
All I can say is that I hope a tranny flush will fix something. Everybody knows how picky these transmissions are when talking about fluid capacity and fluid quality.
 
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