Can i replace my 4.3 liter engine
Can i replace my 4.3liter engine in my 95 GMC
1500 SIERRA With a 350 or 396. I h a 5 speed
But you will need the PCM and wiring harness to go along with whatever engine you put in.
396 big block ->with mods. With time and money you can do almost anything. 350 would be an easy swap. Your '95 is a TBI (Throttle Body Injected) which is a very basic GM OBD1 EFI system. If you found another truck with a 350 TBI and a manual tranny you'd be laughing. These are in any EFI truck van from 87.5 to the Vortec's starting in '96. Basicly you need the engine and anything that looks different like the shorter rad hoses and shorter fan shroud. All the engine accessories and wiring would be the same. The 350 will bolt up to your tranny. Exhaust should connect the as the manifolds are the same (4.3 is just a 350 with the front 2 cylinders cut off). For the fuel and timing you will just need to take the ECM out from behind the glovebox pop open the small cover and swap chips. Once the chip from the 350 manual truck is installed in your ECM it will run the 350 normally (The chip must be from a manual vehicle, you can use any efi 350). If you want to use an older 350 you would need to adapt your EFI to it with parts from a EFI 350 or drop the EFI altogether and go to a carb. If you want a '96 and newer Vortec you will need the MPFI system for that motor and the PCM as Rowefast says above. The 454 would work a few more things would need addressing but the EFI and timing are the same just need the chip from a 454 manual truck!!!