I am going to hazard a guess here and say, probably not. There were so really serious engine design modifications in the 90's that would probably prevent this combination.
The 1991 GMC Sierra typically came with the 4L60 transmission, which is a non-electronic version. The 4L60E, an electronically controlled version, was introduced in 1993. Therefore, if your 1991 model has the standard automatic transmission, it is most likely the 4L60.
4L60E transmission.
That would be the 4L60E transmission.
That would be the 4L60E transmission.
4L60E
4L60e
4l60e
That would be the 4L60E transmission.
4l60e
That would be a 4L60E
Yes it will and it is called a 4L60E transmission.
No 1995 was a transition year from the 1993-1994 OBD-1 to the 1996 and up OBD2. A 4L60E out of a 1995 has to be in another 1995.