I have a 91 full size blazer that's in need of a tranny, but i've been told its a 700R4 and others said its a 4l60e. Chiltons manual shows all auto tranny's for that year are either 4L60 or 4L80E any way to know for sure

 

It will be a 700r4.

 

Thanks a bunch, GM website says its a 4L60 , looking at my buddies blazer same year its identical to his which is a 700R4. much Thanx