1998/99 STS engine swap

[EddieLo]

I have a 1996 STS and needs an engine. I can get either a 1999 or a 1998. Will either fit?

Thank you

Eddie

[KHE]

Either should work in the car. You need to make sure it is a VIN 9 engine since you have an STS. A call to a dealer parts counter would confirm the compatability of the 98-99 engine in your 96 car.

[EddieLo]

Either should work in the car. You need to make sure it is a VIN 9 engine since you have an STS. A call to a dealer parts counter would confirm the compatability of the 98-99 engine in your 96 car.

Thanks Kevin. I'm new on the forum. So how do I check to see about "VIN"? And do I call the dealer once I get this information? Or can I call them simply to ask if a 98-99 will swap?

[hjb981]

The VIN is visible from outside of the car, in a small "window" in the black part of the windshield on the driver's side. I think that the eighth symbol (letter or number) will be a Y if you have the 275 HP engine (like in an SLS) or 9 if you have the 300 HP engine (like in an STS). Wasn't the STS redesigned in 1998? The engines may still be interchangeable, just bringing it up. Are you doing the work yourself, or letting a shop do it?

edit: I think that the VIN is also stamped into the engine block, but I am not sure about that.

/Jonas

[JohnnyG]

I know there were no "dog bone" engine supports on the '99 STS. If you need that mounting boss for your '96, you may have a problem. Best case scenario would be that the mounting holes are there and the part needs to be moved from the '96 engine.

[hjb981]

The dog bones (torque struts) are the engine mounts that go from above the radiator to the sides of the front head of the engine.

[KHE]

Good point on the dogbones. If using a 98 or 99 engine, a Deville engine would have the dogbones. Since the car is an STS, a VIN 9 engine from a Deville Concours should work. A call to the dealer would confirm.