The Enginetech S5671 is a 1-piece ptfe rear main seal engineered as a stock replacement for 1997-2018 Buick, Cadillac, Chevrolet, GMC and more engine applications.
Important Notes
- 1-Piece design: verify your engine uses a 1-piece seal before ordering - 1-piece and 2-piece seals are not interchangeable.
- PTFE construction: low-friction sealing for long-cycle durability.
Specifications
| Brand | Enginetech |
| Part Number | S5671 |
| Product Type | Rear Main Seal |
| Design | 1-Piece |
| Material | PTFE |
| Country of Origin | India |
| OEM / Aftermarket Cross References | FEL-PRO:BS40640, Victor Reinz:JV1657 |
Vehicle Fitment
- Years: 1997-2018
- Makes: Buick, Cadillac, Chevrolet, GMC, Hummer, Isuzu, Pontiac, Saab
- Models: 9-7x, Ascender, Avalanche, Avalanche 1500, CTS, Camaro, Canyon, Caprice, Colorado, Corvette, Envoy, Envoy XL, Envoy XUV, Escalade, Escalade ESV, Escalade EXT, Express 1500, Express 2500, Express 3500, Express 4500, Firebird, G8, GTO, Grand Prix, H2, and more
The rear main seal (also called the crankshaft rear seal) prevents engine oil from leaking between the back of the crankshaft and the transmission bell housing. Over miles and heat cycles, the seal hardens, cracks, or takes a permanent compression set - producing the characteristic oil drip at the bell housing and, if left unchecked, oil contamination of the clutch disc or flex plate. Replacing the rear main seal during a transmission service or engine rebuild restores the final oil seal between the crankshaft and drivetrain, preventing slow leaks and protecting the clutch and flywheel from contamination.
