Description
PAI Industries 636024 rear crankshaft oil seal is a direct replacement for Detroit Diesel 23519651, used at the flywheel-end main seal location on Detroit Series 60 (11.1L, 12.7L, 14L) and Series 50 engines. Single-lip oil seal with 5.187 in ID, 6.506 in OD, and 0.625 in depth. Crosses to Mahle 68007 and Detroit Diesel 23533936.
Signs You Need a New Rear Crankshaft Seal
- Oil weeping or pooling between engine and transmission bell housing
- Oil-contaminated clutch or flexplate at inspection
- Drop in crankcase oil level with no front-of-engine source
- Oil mist on the underside of the bell housing or flywheel
Specifications
| Manufacturer | PAI Industries |
|---|---|
| Part Number | 636024 |
| Part Type | Rear Crankshaft Oil Seal |
| Engine Compatibility | Detroit Diesel Series 60 (11.1L / 12.7L / 14L), Series 50 |
| Inner Diameter | 5.187 in |
| Outer Diameter | 6.506 in |
| Depth | 0.625 in |
Cross References
This rear crankshaft seal replaces or is equivalent to the following part numbers:
- Detroit Diesel: 23519651, 23533936
- Mahle: 68007
- PAI Industries: 636024
Applications
This seal fits the following Detroit Diesel engines:
- Detroit Diesel Series 60 11.1L (1987–2003)
- Detroit Diesel Series 60 12.7L (1987–2007)
- Detroit Diesel Series 60 14L (2001–2011)
- Detroit Diesel Series 50 (8.5L)
Representative vehicles using these engines:
- Freightliner Classic, Century, Columbia (1987–2007)
- Western Star 4900, 5900 (1987–2011)
- Sterling LT9500 / A-Line (1987–2009)
- Coach buses with Series 50/60 (transit and motorcoach)
Replace whenever the flywheel or rear cover is removed. Verify your engine model and serial number before ordering.









