Have an X5 with N52. Thinking of getting an '11 X6 with twin turbo, known issues?
 

Never had a turbo car, are there known issues with the twin turbo? I'm ok repairing NA engines but really dont know much about turbos

Research I found used with warranty turbo set for $1500 for N63. The biggest scare with them are the injectors. They need to be paired so if one fails you need to replace them all. About $2000 parts. Need a special tool to change them.

My N55 the injectors are a lots less expensive and 6 vs. 8.

We were cautious enough to not buy n63 with > 80,000 miles but 9 months later bought N55 model with 145,000

N63 before about 2013-4 will be the mark 1 version without Valvetronic which should make it easier to repair but they had factory problems where BMW did a soft recall they called a customer care package so try to determine if that was done.

Coding the injectors is pretty easy. I've done this before on N54s DME--no problem. Getting the correct index injectors is tricky. Index 11 or 12 is the key here. Both for N54 and N63s. About $300 a pop...for refurbished ones... * 8.... = +$2400...ooofta!

If I were in the market for a N54 or N63...I'd be looking for index 12 injectors installed on it--otherwise, NO DEAL. This is easy to verify with the beauty-valve cover off for the 6 cyl. On the V8...might be more challenging.

I wouldn’t be concerned with modern turbos. 30 years ago, yes.

Just one of the many parts that might fail- no more, no less.

IMO