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4L80E: Delay in 2-3 shift

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Old Oct 17, 2006 | 01:02 PM
  #1  
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Default 4L80E: Delay in 2-3 shift

OK some background on my problem:

I got a new valve body with a different shift kit (I think it's the TransGo Gear Command) from my builder last week and installed in Thursday night. First test drive, it shifts 1-2 fine, then 2-3 releases for a second like it's in neutral (actually shifted 1-2-1), then 3rd finally engaged after a second. The problem started to get better, so I figured it was low on fluid.

Fill it up some more, and finally the problem goes away. But, I way overfilled it because I was retarded and forgot that my driveway is sloped backwards, and I just kept filling and filling. I think I filled it about 4 quarts over, and every time I would drive it would vent out the top of the trans and give me a nice smoke trail and it covered the entire underside of my truck with trans fluid. Dumbass.

So Thursday night I park the truck for the night because everything is finally working ok. Friday morning I wake up and go to work and have only 1st and 2nd gear, it is shifting 1-2-1, so I find out that the 2-3 solenoid is not firing.

Friday night I take it apart again, mess with the wiring, put it together again, drive it, no change. Take it apart again, take out the shift solenoid and mess with it a little bit, tap it on the ground a little bit, reinstall, drive, and it starts out weird again, 1-2-1, then finally 3rd engages. Drive it some more and it gets better and better, finally I have my 1-2-3-4 shifts.

Problem is, 3rd gear actually engages about 2 seconds after the computer commands it. It almost goes 1-2-4 at part throttle, 3rd is only engaged for a split second unless I am WOT, then it seems to work fine. If I put the shifter in 3rd, it will go 1-2-----3, with the long delay. I have watched commanded gear in EFILive and it is a 2 second delay between when the computer changes gears and when the trans actually shifts. If I am cruising in 4th and drop the lever into 3, it shifts immediately, but if I put the lever in 2 then shift to 3 it does the delay. So basically, any time the 2-3 solenoid is commanded to engage, I get a 2 second delay.

Is this just a bad solenoid that I have? Will replacing it fix the problem? Is it a problem with the valve body? Should I just compensate in the tune by commanding 3rd gear sooner?

Last edited by thunder550; Oct 17, 2006 at 01:42 PM.
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Old Oct 17, 2006 | 09:53 PM
  #2  
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weird.....what are your shift times set to? I think i got mine at .200
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Old Oct 18, 2006 | 12:18 AM
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I'll have to check later, tune is on my laptop and I'm on the desktop at home. I talked to Jim again today and he was on the phone with TransGo....they want me to first try a new solenoid, then if that doesn't work R&R the VB again to see if the spacer plate shifted a little bit to cover any holes up partially, and also to take a look and possibly drill the solenoid feed hole a little bigger. Not sure when I'll get a chance to work on it again, maybe not till next week sometime.
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