Will a 6” socket extender work? Or do I need something longer?

 

For the tools list used on my 2016 Ecoboost motor I wrote down a 6" extension and a 9" extension, with a side note for hand use. Meaning the 9" length was good to use to thread in/out by hand when the ratchet wasn't necessary. Further, to clarify that the socket shouldn't be used to thread in until one knows the threads are not crossed.

Probably good to have each on hand just in case it makes it easier overall.
Plus a universal joint is a good idea to connect to the spark plug socket.
As for the socket, I've used the same ole spark plug socket I've had for 30 years (if you are asking about what length socket). I think modern day sockets are magnetic but mine still has the old rubber holder thinking inside.

https://www.f150forum.com/f12/spark-...pleted-478140/

 

Thanks! I’ll buy the 10”.

 

As mentioned previously, having more than one could be useful. Too long and your socket could end up hitting things that the shorter socket is better suited for.

It's been a while and I can't recall all details. I'd just have 2 of different lengths on hand. For the cost of the job to change plugs and boots, the cost of an extension is well worth it. In my opinion.

 

Might I also recommend getting a magnetic spark plug socket as opposed to the ones with the rubber insert. Sometimes, that rubber insert stays stuck to the spark plug and the socket pops off instead of pulling the plug out.