4L80E intermittent problem
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Ok. I did the M6-A4 swap. When the tranny was first put in the shifts weren't firm at all. It would repeatedly hit the limiter between shifts. I checked the fluid to make sure it wasn't low. I used the Lokar dipstick which is a pain in the *** to read the fluid level. Tranny fluid barely stays on the dipstick in the little dimples. So I over filled the tranny. Total miles driven at this point 12 miles.
Once I noticed that I pulled tranny fluid out of it until it was at a good level. I know the fluid was aerated from being over full. The shifts got better and it now shifts where it's supposed to shift. Shifts got better the more I drove it.
Here is the problem now: Sometimes the shifts are firm sometimes they're soft. Yesterday starting from a dead stop the more gas I gave it the bigger the vibration I had. Lots of gas lots of vibration. Not in between shifts just under acceleration. So I parked the car for a few hours until it was time to go home.
I was going to baby it the 35 miles back to the house but it shifted firm and there was no vibration at all. This morning again, no vibration.
It seems like a line pressure issue to me but I'm no auto tranny guy. I don't think it's in the tune either. Maybe the fluid needs to be changed due to aeration? I know with a higher stall it's not going to yank your head off like it would with a stock stall. I did the Transgo shift kit myself. Maybe I screwed that up and it's causing the inconsistent shifting?
Any ideas? I have about 600 miles on the tranny now.
Here is a video but it was shifting fine when I took the video. I was pedaling it high in the rpm's trying to get it to hook up. But then sometimes it shifts really soft and yesterday was the only time I had a vibration:
Once I noticed that I pulled tranny fluid out of it until it was at a good level. I know the fluid was aerated from being over full. The shifts got better and it now shifts where it's supposed to shift. Shifts got better the more I drove it.
Here is the problem now: Sometimes the shifts are firm sometimes they're soft. Yesterday starting from a dead stop the more gas I gave it the bigger the vibration I had. Lots of gas lots of vibration. Not in between shifts just under acceleration. So I parked the car for a few hours until it was time to go home.
I was going to baby it the 35 miles back to the house but it shifted firm and there was no vibration at all. This morning again, no vibration.
It seems like a line pressure issue to me but I'm no auto tranny guy. I don't think it's in the tune either. Maybe the fluid needs to be changed due to aeration? I know with a higher stall it's not going to yank your head off like it would with a stock stall. I did the Transgo shift kit myself. Maybe I screwed that up and it's causing the inconsistent shifting?
Any ideas? I have about 600 miles on the tranny now.
Here is a video but it was shifting fine when I took the video. I was pedaling it high in the rpm's trying to get it to hook up. But then sometimes it shifts really soft and yesterday was the only time I had a vibration:
#2
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I would put a line pressure gauge on it and see what's occurring.
It may be an issue with the shift kit install. There are some features of the TransGo kit I don't care for and one of them may be causing your issue as well.
It may be an issue with the shift kit install. There are some features of the TransGo kit I don't care for and one of them may be causing your issue as well.
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I had thought about grabbing a stock valve body and just doing a quick swap to see if that remedies the problem. I don't like to throw parts at things. I did hook the genysis to it and made sure all the solenoids were active and doing there job. There is no noise from the tranny either.
Just humor me here. where would I install the gauges to monitor line pressure?
Just humor me here. where would I install the gauges to monitor line pressure?
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Got it. I see it. What should the line pressures be? Just a round about figure if you have one. I know Steve did raise the pressures above stock. I guess I'm looking for variations in the pressure though.