4l60E to Ford NP205

[RustyC]

Looking at the mating a 1996 up 4L60E with the 6 bolt rear case and factory 6 bolt t-case adapter to a Ford NP205.
I am currently running a TH350 to Ford NP205 behind an 5.3 LS and looking for lower gearing. I do not want to go lower axles gear because I'm running flipped 9"s / 5.13 in a rear engine setup.
I did have a 4.3/th350/dana 300 in the same rig and it felt plenty low enough, then swapped in the 205 ,now a 5.3 LS and still want a little lower gear.
Pinions are small as is.
My thoughts are using the 27 spline female to 31spline spud shaft from my current setup with the factory 4l60e six bolt adapter and my 205 with clocking ring. Has anyone done this combo???
My 205 has a speed sensor on it now so I'm good there. I have also read of a 32 spline 4L60E output shaft used in a ZR2 but have not confirmed this.

TH350 + Dana 300 + 5.13 = 33.74 ratio in first gear. Plenty low enough.
TH350 + NP 205 + 5.13 = 25.34 ratio in first gear. Not low enough.
4L60E + NP 205 + 5.13 = 30.77 ratio in first gear. May be just right.

The other option is an Atlas T-case but honestly I like the old 205 and a transmission swap would cost less.

Using a Winters shifter now with a TH350 rockcrawler gate. Will my same shifter work with a 4L60E using new hardware at the trans and new 4 speed gate?

 

[CheapthrillB2]

Looking at the mating a 1996 up 4L60E with the 6 bolt rear case and factory 6 bolt t-case adapter to a Ford NP205.
I am currently running a TH350 to Ford NP205 behind an 5.3 LS and looking for lower gearing. I do not want to go lower axles gear because I'm running flipped 9"s / 5.13 in a rear engine setup.
I did have a 4.3/th350/dana 300 in the same rig and it felt plenty low enough, then swapped in the 205 ,now a 5.3 LS and still want a little lower gear.
Pinions are small as is.
My thoughts are using the 27 spline female to 31spline spud shaft from my current setup with the factory 4l60e six bolt adapter and my 205 with clocking ring. Has anyone done this combo???
My 205 has a speed sensor on it now so I'm good there. I have also read of a 32 spline 4L60E output shaft used in a ZR2 but have not confirmed this.

TH350 + Dana 300 + 5.13 = 33.74 ratio in first gear. Plenty low enough.
TH350 + NP 205 + 5.13 = 25.34 ratio in first gear. Not low enough.
4L60E + NP 205 + 5.13 = 30.77 ratio in first gear. May be just right.

The other option is an Atlas T-case but honestly I like the old 205 and a transmission swap would cost less.

Using a Winters shifter now with a TH350 rockcrawler gate. Will my same shifter work with a 4L60E using new hardware at the trans and new 4 speed gate?

I built an adapter plate that bolts onto the 4L60 and allows me to bolt a cast iron Ford c6 adapter to it, then a 205 behind that. I bought the advance adapters spud shaft.

Crude outcome, but I don't have access to alot of fancy tooling. Seems to work well and doesn't leak.... Yet.



I had a 5.8/c6/205 in my buggy. I went to a 5.3/4L60. I wanted to keep my tcase where it was and didn't wanna change my tcase shifter setup. Doing what I did allowed me to retain crossmember/mount/shufters/driveshafts etc with no change.

 

[CheapthrillB2]

 

[RustyC]

Looks like that works Just fine. Good info. Is there any issues with front drive shaft clearance.
I'm hoping to pick up a transmission core soon in test fit with, then rebuild if it works out.

 

[CheapthrillB2]

I run a three piece shaft. The "fixed section" runs along the case. It's tight by the art Carr shifter bracket. Besides that, plenty of clearance. Probably more then I had with my c6.