[markinnh]

What year did GM switch to the 233 from the 231? And what year did they go from the 700R4 to the 4l60E?
I have a 2004 S-10 and I wish to remove the electrical part of the 4x4 and put in an older floor shift for the 4x4.
My Astro has a 700R4 with a 233, and I made the shift linkage to use a homemade shifter. Not totally my design, I used someone's design and modified it for my van as his was 2002 and mine is 89 (with 98 frame) But to do this on my s-10 O need to know the years to do the shifter right, so it will go into low 1. Thanks, Mark

 

[bk2life]

what year did they go from the 700R4 to the 4l60E?

In 1990, General Motors changed the name of the 700R4 to 4L60, which represented 4-speed, longitudinal, 6,000-pound gross vehicle weight rating. In 1993, the transmission's hydraulic shifting system was replaced with electronic controls for the 4L60E version.

 

[oldeerslayer]

The switch to the NP233 was over a few years from 1992 -1996. Blazers got it before the trucks. IDK if a buyer back then had a choice or not. By 96 all were electric. But there were 233's as early as 92. There was also 2 different front yoke styles and 2 different rear spline counts. Early were 27 spline output shaft. Later were 32. I believe that's where you could run into trouble with an early NP231. You'd need to change the driveshaft front yoke. You might end up needing a hybrid u-joint.