1. 1IMS (intermediate-shaft) bearing: the sealed ball bearing gets no continuous oil feed and, if it fails, can let the timing drift and destroy the engine. Crucially, the 1998–1999 996.1 cars use the sturdier dual-row bearing (~1–2% failure); Porsche switched to the weaker single-row unit around MY2000 (~8–10% failure), so the earliest cars are the lower-risk M96s. A retrofit typically runs about $2,000–$3,500 with labor and is worth doing during any clutch job.
2. 2Bore scoring, cracked cylinders and slipped liners are the more serious M96 failure — they can require an engine rebuild or replacement. Early dual-row cars see them relatively rarely, but the risk exists across the M96 range, so look for evidence the engine has no scoring history.
3. 3Weeping rear main seals (RMS) are common on the M96; check for oil at the bell-housing and factor a reseal into the clutch/flywheel work these cars eventually need.
4. 4US-market cars fall under the only factory recall these 911s carry, NHTSA 00V109000 (about 2,734 vehicles, notified April 2000): an instrument-cluster (electronic logic unit) programming error could show an incorrect fuel level and let the car run low and lose power. The remedy is a cluster software reprogram, not a fuel-sender part, so confirm a VIN check shows it was done.

• 00V1090001999–2000
  Instrument-cluster software error could show an incorrect fuel level and let the car run low and lose power.

US NHTSA campaigns for this model. A listed campaign may not apply to a particular car, and may already have been remedied — check a specific car by VIN at nhtsa.gov/recalls.