View Full Version : Engine swap

08-25-08, 05:18 PM
I have a 1997 STS with a bad head gasket at 93k miles, I found a 4.6 Northstar from a 1994 to swap, does anyone know if a 94 will work in my 97? And if not what are the differences?

Thank you all for your help. I'm a new Caddy owner and wasn't aware of the head gasket issue before I bought one.

08-25-08, 07:58 PM
A 94 won't work. There are threads that tell you what years work.

My advice: don't waste time and money on an unknown engine. If yours runs fine, except for the HG's, fix them and be happy. It is only a little more work than swapping engines.

08-26-08, 09:55 PM
zonie is correct - on my '97, I had my first engine replaced with a used engine, due to head gasket failure. When that engine's head gaskets failed, I learned about the proper fix on this forum and chose to repair the engine following advice from zonie and many others. Now I have an engine I can rely on.

08-26-08, 11:13 PM
A 94 has a few differences in the block, but could be made to work if the price is right. The AC compressor will have one bolt that won't line up and the motor mount on the passenger side will have to be modified as there is a bolt near the bottom of the front cover that is not there on the 94 block. I totally agree that fixing your engine is the way to go.......