Is this tuning or a mechanical issue?
Thread Starter
TECH Apprentice
Joined: May 2006
Posts: 308
Likes: 0
From: Nebraska
Is this tuning or a mechanical issue? How do you address a rpm flare/spike between shifts with tuning software?
Basically, under heavy load, my built 4L60E will flare/spike while shifting between 2nd and 3rd gears. Specifically, it feels like the trans slips into nuetral (2nd band disengages), the rpms spike(up to 500rpms at full throttle), before returning back to previous rpm for the shift into 3rd gear(3/4 clutch engages).
Basically, under heavy load, my built 4L60E will flare/spike while shifting between 2nd and 3rd gears. Specifically, it feels like the trans slips into nuetral (2nd band disengages), the rpms spike(up to 500rpms at full throttle), before returning back to previous rpm for the shift into 3rd gear(3/4 clutch engages).
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
Did it just start happening...?
If it did, and if no DTC codes are present, and if the airmass calc is correct (MAF working right, and/or VE table correct), then it is mechanical/hydraulic [impending] failure.
Oh, did you check your fluid level...? Fluid condition (color/smell)...?
If it did, and if no DTC codes are present, and if the airmass calc is correct (MAF working right, and/or VE table correct), then it is mechanical/hydraulic [impending] failure.
Oh, did you check your fluid level...? Fluid condition (color/smell)...?
Thread Starter
TECH Apprentice
Joined: May 2006
Posts: 308
Likes: 0
From: Nebraska
It's been like this ever since I bought it 2.5yrs ago....It's never been to the track and I haven't driven WOT that much due to working on changes with the engine. Now that I have the engine right, and starting to drive at WOT...it's still there and getting worse. No DTCs, MAF and VEs are correct, fluid is ok...a tiny bit of silver-metal but nothing substantial...
every 60 I have seen do this was on it's way out. I'm not a trans guy, but something about the clutches pushing past a snap ring and running over onto the drum... I had one begin doing this during tuning a few weeks back. The owner insisted I press on. He called the next day and told me that it failed in front of his house while he was pulling on it for good.
