I think I heard a video in which a GM engineer was saying they put chains on both the front and rear of their 2.7 turbo engines. The front is for timing. The rear is to power the oil pump and balance shafts. He acted like this kinda stuff is now common by car makers and some even use belts instead of chains. Have you heard of this design practice and have any thoughts on it? If they have occasional problems with the chains on one end of the engine, I hate to think there might be a second chain on the other end to also have to worry about.
It’s absolutely normal to have 2 chains, it’s actually even preferable to have a chain driven oil pump than a direct driven one (for some reason it tends to be more reliable).
I doubt wether they’re on opposing sides of the engine as usually they’re on the same one - in this configuration:
