Nice SSer

iTrader: (13)

I recently did a 4L80E conversion in my SS. It has a freshly re-stalled 3800 Precision triple disk converter and I am running the TCI Outlaw Shifter with the 4-speed gate. I am also using the speartech add-on harness. The car runs great gears 1-3 but it will not shift into overdrive or lock up the converter. The transmission is fine internally (bought it from a member on here and it was a mess initially - only had park and neutral; then took it out and had a local guy go through it and fix all the issues). Once fixed, I had New Era tune it but they could not get it to shift into OD on its own while driving around town. The weird thing is when Mike had it on the dyno, he could command the transmission to shift into OD AND lock up the converter everytime he told it to. It leads me to believe it is a tuning or electrical issue but with New Era not being able to figure it out and the next closest tuner six hours away, I'm stuck with a TH-400 and 4.10s in a car I like to be able to drive on the highway. I really hope I can solve this issue locally. Anyone had a similar issue or know what it could be?

jeremyfrank14

iTrader: (19)

How are you controlling the transmission? Segment swap or relay mod?

Nice SSer

iTrader: (13)

They did a segment swap

LOWnEASY

iTrader: (1)

Sounds like its in the tune if it can be commanded into od/lock up. If it didn't go in when being commanded with the scan/tune tool, I would say tCC solenoid but that's no the case. This is just my opinion, but I'm no trans expert either.
I have a similar problem but work hasn't allowed me to get it to a shop for a diagnostics test.

Nice SSer

iTrader: (13)

I spoke with Speed Inc and Texas Speed and they both told me they did not think it was tune related. I don't know what else it could be and I didn't think it was inside the transmission if it could be commanded. I am pretty much out of options, I am going to email my tune to Speed Inc and have them look it over. Anyone have any other ideas?

jimmyblue

iTrader: (11)

OK, let me ask you this. Is using a segment swap and
a conversion harness too, something like a double negative?

Meaning that perhaps TCC control polarities (which, I
gather, differ) are not swapped and so not working?

Are you sure it is not entering OD, and not just failing
to lock up?

Nice SSer

iTrader: (13)

When I take off from a stop it starts in first, shifts into second, then shifts into 3rd and just stays in 3rd no matter how fast I go. Mike mentioned if it had a manual valve body and took the electronics out of it, the transmission should work. But I want to be able to put it in drive and go. He also mentioned that a stand alone controller may be a good place to start but I already spent money on the speartech and have way too much money into this build as it is. I hate to just keep throwing money at it not knowing if it is even going to solve the problem.

68BBChevelle

iTrader: (12)

Ever find a solution to this? Im having same problem.

GARAGE_BUILT_Z28

iTrader: (20)

same here smh

maxdmaro

Me too same problem.

68BBChevelle

iTrader: (12)

Mine ending up being shifter cable linkage problem.

Area 51 Racing

iTrader: (5)

Do the 4l60e to 80e relay mod so a segment swap isn't needed. My tuner recommend it since he had several cars with OD problems and this fixed them. It's very simple but I can't report on it yet since I'm still in the middle of my build but I'll find yall the link I used.

Here it is
http://www.performancetrucks.net/forums/tuning-diagnostics-electronics-wiring-161/run-your-4l80e-swap-4l60e-tune-no-segment-swap-486918/page6/