Well first off I'm Brian,my truck is an 84 gmc sierra 2 whl drive 305( I think) this is not the original motor or trans , the trans is 3spd with overdrive automatic. My first question is how can I tell what motor it is.I'm not a gm guy so its all new to me , the truck has treated me well and is in decent shape but the drive train is slowly dieing. I have no idea what is inter changeable or what years will work as in the motor and trany department.So I will start with motor identification then what year or years v8 can be put in , like a 350 , this will be the first of many question so bare with me, thanks.

Welcome to the site.

You need a Casting code to tell you anything, This Casting number is usually found at the rear of the block on the left or drivers side on top of the bellhousing flange. Find the number, then go here. http://www.chevy-camaro.com/chevy-ca...es.asp?group=1

Welcom to the site! Hope u feel at home..

Any thing that started out as a 350 will fit !! Heck even a 305 or a 327 will fit.

transmission is not an issue either.

Welcome to the site! Got any pictures of the truck you want to share with us?

cool beans thanks for the replies, no pics off the truck not very pretty hoping to get some body work done on ti ,it deserves it , its treated me well.