Caterpillar part numbers starting 1W1
| 1W1251 | Gasket (turbocharger, air lines) | Caterpillar | ||
| 1W1253 | Gasket (aftercooler) | Caterpillar | ||
| 1W1256 | Pipe (l.h.) (turbocharger, air lines) | Caterpillar | ||
| 1W1258 | Housing (aftercooler) | Caterpillar | ||
| 1W1260 | Housing (aftercooler) | Caterpillar | ||
| 1W1372 | Base assembly (push rods and valve lifters) | Caterpillar | ||
| 1W1563 | Handle | Caterpillar | ||
| 1W1564 | Screen assembly | Caterpillar | ||
| 1W1641 | Tube (oil lines, engine) | Caterpillar | ||
| 1W1801 | Insert (cylinder heads and valve) | Caterpillar |