You have a 4L80E transmission in a 1991 Chevy truck???? That unit was not available in 91......... (I will monitor this question for a few days) why do folks post a question and never return for the answer?????????????? well, forget it doofus, if you cannot answer, get your replies elsewhere
If it's an automatic, you have a 4L80E. If it's a manual, it's an NV4500.
That will be a 4L80E. transmission.
The 1/2 tons used the 4L60E in them. The 3/4 tons used the 4L80E in them.
That would be a 4L80E
with no problem. you could bolt a 572 in. remember trans will have to be a 4l80e trans. and if its carb just use a turbo 400 trans
To make that transmission work. You would have to install a computer and wiring harness and speed sensors. That would be alot of money. The 4L80E is a electronic controlled transmission.
If it is a 1/2 ton then it will be a 4L60E transmission. The 3/4 ton will have a 4L80E in it.
That would be a 4L80E automatic transmission.
1/2 tons have the 4L60E in them. 3/4 tons used the 4L80E trans.
It will bolt up but the wireing harness on the 1500 / 1/2 ton will not plug into the 4L80E transmission, there for it won't work. The 4L80E transmissions are for the 3/4 ton trucks and YOURS is a 1/2 ton and it REQUIRES a 4L60E transmission to be put back in it.
The 1/2 ton will have a 4L60E transmission in it. The 3/4 ton will have a 4L80E in it.
The 1/2 tons used the 4L60E and the 3/4 tons used the 4L80E