4L60E SWAP TO TH475

[xxsharkboyyyxx]

Hello all, new poster here

I am looking to swap in a TH475 in place of my cracked 4L60E on my 1994 K1500 4WD. From what I have read up on a NP241C and NP208 adaptors are same. One is driver side drop one is passenger side drop. I know I need a 32 spline output on trans or input to transfer case. Has anyone done this type of conversion with the NP241C and a TH400/TH475? What all am i getting myself into? How much modifications need to be done? Those that have, do you have a part number for adapter? Google is never any help.

 

[Scooterwrench]

Wasn't TH475's the transaxles used in Eldorado's and Toronado's?

 

[Schurkey]

The 475 is a heavy-duty version of the TH400, often used in school-bus chassis or motor-home chassis. The drums had the max number of clutch plates, and the geartrain had straight-cut planetary gears.

The FWD Toro/Eldo from '66 to 78 model years was the 425. The guts of the transmission spun "backwards" compared to the 400. One-way clutches had to be reversed to work properly.



You're giving up overdrive, and you're giving up a locking torque converter. Fuel economy will suffer. Consider a 4L80E and matching transfer case from a donor truck, instead.

No promises on how to keep the computer happy, since it thinks it's in charge of controlling the shift points.

No idea on how to connect the transfer case. Yeah, you'll need a 32-spline transfer case input shaft.

 

[xxsharkboyyyxx]

You're giving up overdrive, and you're giving up a locking torque converter. Fuel economy will suffer. Consider a 4L80E and matching transfer case from a donor truck, instead.

The truck is a built 383 with 9 inch lift and 37x13.50 tires. Fuel economy is the least of my concerns.