Tranny problems, think I finally killed it
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From: Knoxville, TN - Cedar Bluff
Tranny problems, think I finally killed it My transmission started shifting weird last week and has gotten worse, especially on the way to and from the F-body Gathering in Atlanta. It's going from 1st gear to 2nd, slipping out of 2nd and 3rd really fast then bogging in overdrive. It only does this taking off slowly, just regular driving. If I stomp it out of a light it shifts fine. This problem is becoming more frequent, I did a burnout in front of GMMG on Friday and turning left onto the main road it went from 1st straight to 4th gear, I let up and manually pulled it back to 2nd and it pulled out fine. I don't think it's slipping, it acts like a computer issue or shift solenoid. I just wanted to see if someone could give me an idea of what is going on. The SES light hasn't come on either.
Thanks,
Mike
Thanks,
Mike
If it quick shifting sounds like a control issue. Aslo you may want to check air filter and maf.
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From: Knoxville, TN - Cedar Bluff
Originally Posted by performabuilt
If it quick shifting sounds like a control issue. Aslo you may want to check air filter and maf.
Control issue? Also what does the Air Filter and MAF have to do with the tranny shifting? I don't know jack about these 4L60E's. It just started doing this and has become more and more frequent as I drive it. Wouldn't the computer flash a trouble code if the MAF or something wasn't reading correctly? It goes straight from 1st gear and almost completely skips 2nd and 3rd till it hits overdrive.
No it would only set a maf code if the maf failed or was out of its entire operating range. Air filter can affect maf readings particularly the aftermarket oiled type. Theres actually a GM SERVICE buletin about that and that it can cause damage to the trans from low presure and irractic shifts.
Several people have had the issue you have also after a large cam install again causing the maf to give false signals , Of course this isnt the only possibility the TPS could be at issue also . But the trans it self has no control over when it shifts to the next gear its strictly a PCM comand issue. It must either do what its comanded or slip , Those are its only options. I would look at tuning first and sensors as the trans upshifting quickly is not going to be a transmission issue. Not to say theres not some damage to you trans its hard to say but thats not why its acting as it is. I will say this if you continue driving it that way then it will become a trans issue and you will need one.
Several people have had the issue you have also after a large cam install again causing the maf to give false signals , Of course this isnt the only possibility the TPS could be at issue also . But the trans it self has no control over when it shifts to the next gear its strictly a PCM comand issue. It must either do what its comanded or slip , Those are its only options. I would look at tuning first and sensors as the trans upshifting quickly is not going to be a transmission issue. Not to say theres not some damage to you trans its hard to say but thats not why its acting as it is. I will say this if you continue driving it that way then it will become a trans issue and you will need one.
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OK I'm tracking now. I had the car tuned last fall with the shift points set and torque management removed. I'm not getting any codes at all. The Air Filter is a K&N but it hasn't been oiled in ages, I just clean it and leave it dry to prevent getting oil on the MAF. I had that happen before, the motor runs great but I guess plugging into the computer to see whats going on would be the only way to tell wouldn't it? I'll call my tuner and see if he can take a look to see what my computer is doing. It only does this taking off slow and from time to time but is becoming more common the more I drive it. I'll park the car until we can take a look. Thanks for your help!
Your welcome and you should be able to fine all the answers you need or at least get a direction to look in that way .
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From: Philly
Originally Posted by 98-LS1
or shift solenoid
first thing you should do is change the shift solenoids. they're not too expensive and you could probably do it yourself, so why not give it a shot? 
