I've owned many cars & still have (3) I drive regularly. Never had to rebuild an engine, trans, replace a water pump or diff & I drive them hard. My secret;
1. Ceratec (every 50,000kms) with oil (engine) change.
2. Oil (engine) changes & filter every 5,000kms
3. Trans fluid change every 20,000kms
4. Diff fluid every 20,000kms
Full Synthetic on all of the above, premium oils.
5. Replace coolant with *premix coolant every 20,000kms.
* Never buy the concentrate & mix with tap water, the premix is already 50/50 with demin water.
In addition, I have a workshop & do all my own servicing. I've found some places, who say they've changed the oil filter, but haven't & pollen filters on a Mustang are a bit fiddly, they invariably tick the box & but haven't done it.

 

Thanks for your feedback and for the tips, it's much appreciated.