4l60e Interchangeability question

[Zee_7D_one]

I have a 1996 Silverado extended cab with 4.3 V6.
The transmission went bad in it a while ago so I went to the junkyard and grabbed another one, but the only ones they had came out of 01-02 Chevy Blazers. Thats Blazer NOT Trailblazer.
So anyway I ended up going with an 01 Blazer tranny, and it is nearly identical to the old one with the exception of the pan, it is slightly different.

Now the truck runs and drives, and seems to have all the gears but the way it shifts seems a little sloppy with it sometimes feeling like it is slipping a little in between shifts, maybe just delayed for some reason, I don't know. Also it seems to shift a little better under hard throttle, under light acceleration you can BARELY feel it shifting if at all sometimes like it just slides into the next gear.

Both of these transmission are bolt on bellhousing by the way.

My question is are these 2 transmissions completely interchangeable with each other or are there differences? Any help would be greatly appreciated

Thanks guys

 

[Zee_7D_one]

Anyone???

 

[jdla140]

It should shift fine, but the 01 trans has EC3 PWM lockup. Even if the TCC locks at all, **** will break soon. You need to find a 96-97 trans, those are the only ones that are directly interchangeable. You MAY be able to get away with a valve body swap to 96-97 style but I wouldn't count on it. 98+ blazer 4l60e's are the same as NBS trucks. I put a 98 4.3 blazer 4l60e in my 99 NBS 5.3 last year and it worked great.