Built 4l60 slipping 2-3 shift
Built 4l60 slipping 2-3 shift I'm having a problem with a build 4l60 slipping on the 2-3 shift only. I have shift time set at 0, line pressure maxed out. It doesn't matter where I set shift points at it will go to shift when I tell it to bounce of the rev limiter then shift into 3rd. It does it on motor 380whp and nitrous 500whp. Its taking .9-1.0 sec to complete the shift.
Any ideas
Any ideas
Try turning off kick down in the tuning , You will still have under throttle but several people have reported this having solved there issue
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Never heard of it. You can raise and lower downshift speeds, nothing about kickdown.
IMO the trans needs to come apart to properly fix a problem like that. It can be fine tuned with tuning but one second to complete a shift seems like a lot.
IMO the trans needs to come apart to properly fix a problem like that. It can be fine tuned with tuning but one second to complete a shift seems like a lot.
I had and individual contact me a little while back and he found that setting and turned it off . Personally I do not know where it is either but he did say that after repeated attempts replacing building trans etc he kept having that same issue and he said that solved it. his shifts were perfect in all positions he said prior to that except for WOT just off and all was fine, After he did that all was fine in all throttle positions including WOT
So I don't know may be something different in this case but was his solution apparently I will ry and find the info he sent I think he sent it in a PM also
But I am not obviously a tuner and he could have been using the wrong name but maybe some setting that tells the PCM the car is at WOT.
I did find a place in EFI LIVE called throttle kick down I wonder if he ment he raised the TPS there for kickdown to above 100% for the 3-2 ?
So I don't know may be something different in this case but was his solution apparently I will ry and find the info he sent I think he sent it in a PM also
But I am not obviously a tuner and he could have been using the wrong name but maybe some setting that tells the PCM the car is at WOT.
I did find a place in EFI LIVE called throttle kick down I wonder if he ment he raised the TPS there for kickdown to above 100% for the 3-2 ?
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Last edited by performabuilt; Jul 17, 2008 at 06:30 PM.
I had the problem after a full transgo install and ended up adjusting the 3-4 clutch clearance, seperator plate hole sizes (several times) and tuning the upshift pressure modifiers. I probably didn't have to do it so many times but I wanted it perfect.
There is of course the possibility of a mechanical failure or clearance issue. But this gentleman called me I beleave and he says only has 120 psi at wot at the pressure port. Which may very well be the problem. I told him to unplug harness from trans and that it would set codes but see what the PSI is then. if its 200 to 230 then its a tuning issue if its still 120 its a trans or PCS issue. Trans is from a NON sponsor here but reputable company
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Verdad Gallardo There are many possibilities ranging from it just being set to low to a bad sensor or out of range like the MAF or TPS you have 240 max line but at WOT plugged in your only have I think you said 120 I cant really give you alot of direction at this point other than looking at tuning you are now on the right track. Hopefully the trans has not been damaged yet, I would post and ask some questions in the tuning section. Likely you will have to do some data logging to figure out why the pressure is being commanded so low at WOT
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FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
I'm glad you called earlier... it was good talking to you on the phone.
My system didn't save your # so I could not call you back. But, I spoke to Vince at FLT not long after the call. We had some catching up to do and I mentioned our discussion.
He was quick to remind me about the fact that the MAF sensor could be contaminated with oil from the air filter. Take a very long look at those log files again... check for odd MAF sensor reporting.
That can and indeed will drive the Line Pressure to dangerously low settings!
Also, be sure to take a look at the fluid level and condition. If the fluid is discolored and smells then there is a good chance this unit is hurt. Like I told you on the phone, I have nothing but respect for the shop that built it... these things happen and that's the exact reason I run a Vacuum Modulator on my performance units!
Don't hesitate to call me Monday if you need to.
g
My system didn't save your # so I could not call you back. But, I spoke to Vince at FLT not long after the call. We had some catching up to do and I mentioned our discussion.
He was quick to remind me about the fact that the MAF sensor could be contaminated with oil from the air filter. Take a very long look at those log files again... check for odd MAF sensor reporting.
That can and indeed will drive the Line Pressure to dangerously low settings!
Also, be sure to take a look at the fluid level and condition. If the fluid is discolored and smells then there is a good chance this unit is hurt. Like I told you on the phone, I have nothing but respect for the shop that built it... these things happen and that's the exact reason I run a Vacuum Modulator on my performance units!
Don't hesitate to call me Monday if you need to.
g
As always nice talking with you Gil. It definitely sounds like the problem is in the vehicle. Weather or not it has already hurt the trans, time will tell depending on how many hits at wot have been made. b18c1hybrid stay in touch with your builder. If the trans needs to be returned be up front and honest with them. I know when a customer has an issue with one of our units the more info we have the better. Plus honesty goes a long way with me. They might just charge for the parts or maybe not at all. I know those guy's and they will do you right. Good luck. Vince
