Maintenance only extends engine life when the parts match the engine. A filter with the wrong bypass, a liner kit for a different bore, or a seal that swells in the oil you use will undo the labour.
Where “close enough” fails
- Gaskets that almost align and then leak after heat cycles
- Bearings with the right stamp and the wrong clearance
- Sensors that plug in and send a different range
- Hoses with the right length and the wrong pressure rating
OEM parts follow the latest part number for that serial. Good aftermarket parts state their brand and the specification they meet. Both can be the right choice. An unmarked part with no spec is not a third option. It is a risk.
Ask for the basis of the quote: OEM, or which aftermarket line. Then decide with the hours and the cost of another failure in view.