Swapping 700r4 to 4L60 (or possibly 4L80)

[HotRodPC]

Ive done the 4l60e servo swap, the question was is the upgraded servo in the 4l80e worth doing

It's actually not needed in the Th400 or 4L80-E. They are bigger servos and wider bands already so they hold tighter as is. About the only thing you could do is maybe a shift kit that might open up an orfice in the seperater plate that would allow more fluid pressure for maybe a quicker apply of the servo. Honestly, not so sure it would work anyway in a 4L80-E being it's computer controlled and solenoid shifted, but it could and does work in the Th400 for certain.

 

[usar17]

You must be registered for see images attach

Score!! 1994 4L60

 

[HotRodPC]

Yepper, with a driver side drop Tcase.

 

[usar17]

I left the transfer. Anyone know how to convert a NP 208 to electronic signal for this system?

 

[HotRodPC]

I left the transfer. Anyone know how to convert a NP 208 to electronic signal for this system?

Prolly best to try and find a NP241C from an 89-91 K5 Blazer, Jimmy or Burb. they are passenger side drop. My concern here for you on that, and it's because I'm not sure and don't know on the later models, is that output shaft going to be the correct length for your NP208/NP241C? Hopefully there's only 1 size 4x4 output shaft for 700r4/4L60-E's.

 

[usar17]

I would hope they didn't change that. Hmmm ...oh wait. I could probably just reuse the output shaft from my 700r4 if it is,....right?

 

[HotRodPC]

I would hope they didn't change that. Hmmm ...oh wait. I could probably just reuse the output shaft from my 700r4 if it is,....right?

yes you could if that's the case. Real easy to tell. Just pull the adapters off of both and see how much output shaft is sticking out off the back of the case.

 

[usar17]

I PM'd retro about the speed sensors.

So rebuild parts... How does this look?

Rebuild kit:
http://www.transmissionpartsusa.com/4L60E_Transmission_rebuild_kit_1993_94_p/350-000035003.htm

Corvette 2nd gear servo:
http://www.transmissionpartsusa.com/700R4_4L60E_Corvette_servo_piston_p/350-000035952.htm

Beast sun gear shell:
http://www.transmissionpartsusa.com/700R4_4L60E_The_Beast_sun_shell_p/350-035823ahd.htm

anything else recommend? bands, sprags, washers, bushings, solenoids, pistons, bearings or just wait and see what needs replaced on top of these when I dive into it

 

[HotRodPC]

I PM'd retro about the speed sensors.

So rebuild parts... How does this look?

Rebuild kit:
http://www.transmissionpartsusa.com/4L60E_Transmission_rebuild_kit_1993_94_p/350-000035003.htm

Corvette 2nd gear servo:
http://www.transmissionpartsusa.com/700R4_4L60E_Corvette_servo_piston_p/350-000035952.htm

Beast sun gear shell:
http://www.transmissionpartsusa.com/700R4_4L60E_The_Beast_sun_shell_p/350-035823ahd.htm

anything else recommend? bands, sprags, washers, bushings, solenoids, pistons, bearings or just wait and see what needs replaced on top of these when I dive into it

I'd prolly go with the wider 2/4 band also, either the Raysbestos Z pack or Alto Commercial 3/4 clutch pack.

If the budget can afford it, cuz it's about $85 alone, the SuperHold 4th gear Servo by Sonnax. I've never used one yet, but I intend to on my build for my 700r4. We all know we're not supposed to use 4th gear to tow. I intend to give it a try with this Servo installed. So it'll be a trial deal for me. I'd like to see if I can tow about 5000lbs in OD and see how it holds up. Worst it can do is burn up the 4th gear clutches and/or 2/4 band then I'll know next time.

 

[usar17]

I'm gonna stick with the vette.

So instead of the rebuild kit get their gasket kit then some good clutch packs? Or do I still need the rebuild kit for the other clutches and steels

 

[usar17]

Ugh...so I found a truck and pulled the wiring. Then released it was 11/94. So its a 1995 model year how worthless is this harness with a 1994 4L60e? I know this is right around when changes were made

 

[HotRodPC]

Ugh...so I found a truck and pulled the wiring. Then released it was 11/94. So its a 1995 model year how worthless is this harness with a 1994 4L60e? I know this is right around when changes were made

I think you may still be alright. The change in 95 was the pump was PWM(PulseWidthModulation) and I don't think that will matter on the vehicle wiring. It would just matter on the internal wiring of the transmission I do believe. Maybe someone else can be certain about that.

 

[usar17]

....still waiting for someone to confirm what HR said.

I know the 95 PCM is set up for PWM and the harness has 12pins for the PWM addition.
1994 has an 11 pin setup for the tranny. Now if I use the 94 PCM and Tranny with the 95 Wiring harness I should be good so long as all other PCM pin-outs are the same, correct?

 

[HotRodPC]

....still waiting for someone to confirm what HR said.

I know the 95 PCM is set up for PWM and the harness has 12pins for the PWM addition.
1994 has an 11 pin setup for the tranny. Now if I use the 94 PCM and Tranny with the 95 Wiring harness I should be good so long as all other PCM pin-outs are the same, correct?

I'd really have to think that the 12th pin is the only difference and if your using a 94 harness that is only 11 pin, that should leave the 12th pin dead and unused. I just don't have a book to confirm that any of the pins were moved around. I'd say install it, and see how it runs. I have a feeling the pins should be all in the same spot, you just won't be having a 12th pin to feedback to the ECM and you don't need it with a non PWM transmission.

 

[usar17]

Ok I got the rebuild kits in today to start tearing into this 4l60e.

I've looked around and seen a lot of different suggestions regarding fluids to use while rebuilding the tranny. Vasoline on the check valves being one. Soaking parts in atf prior to assembly being another. Or using assembly lube. But I'm planning on rebuilding this now and it may not go in the truck for a month or two... thoughts?