Looking at buying another truck. It has high miles showing but owner says engine has been replaced by a previous owner. No paperwork on engine. It runs great but is there a way I can tell if this is the factory or original engine and is there a way I can trace this one back and find out for sure.

 

There are build date stickers on the side of the heads and front timing covers. See if those match the trucks build date. Even then though, the engine could have been built long before the truck. But, if a newer engine was installed it would be obvious if the truck was a 2000 and the engine had a sticker on it saying 2002.

If there are no other ways to tell (bolts been removed recently, parts that are updated from a newer model etc) then treat the truck and the price as if it had the original engine. If there is no paperwork to show a new one or less mileage engine was installed, then consider it hasnt. Not saying that it did not happen, but there is no proof that it did. Plus, the transmission, 4x4 (if it has it) rear axel and all other rotating/moving parts have high mileage as well.

 

Thanks for the advise I appreciate it alot.

 

Rebuilders probably remove the stickers. If it was a junkyard engine, they may still be there but may or may not be readable.