C6.4 vs C6.6: how do you verify parts?
Do C6.4 and C6.6 use the same parts?
The C6.4 and C6.6 codes do not establish part interchangeability. Record the full engine model, serial number and removed-part reference. Cat resources distinguish equipment families and request serial identification for parts searches; that identification matters more than a similar model name.
Why is CAT 320D alone insufficient?
Cat's official catalogue includes a 320D/320D L designation with C6.6 engine, while our 320-0413 injector listing names a C6.4 application. Read your own machine plate instead of generalising one installation to all 320Ds. We do not publish an unverified equivalence table.
What should a reliable enquiry include?
Send machine and engine plates, the old-part reference photo and required function: injection, cooling, filtration or hydraulics. Keep every suffix and character. If a marking is unreadable, photo search can help extract a number but cannot replace technical validation.