- Engine configuration and basic structure are consistent with the base engine, so the customer could more easily replace components;
- Every engine has gone through the same test processes as the original engine to ensure that the parameters are up to delivery standards;
- Engines that have reached the overhaul period;
- Engines that need technology or emissions upgrading;
- Engines that have quick maintenance requirements (e.g. intercity buses);
- Engines with poor operation status (e.g. non-Weichai user replacement);
- Engines with serious failure out of warranty that need replacement instead of repairing.