What are the common problems with the 1999 Porsche 911 Carrera's IMS bearing?

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The 1999 Porsche 911 Carrera (996.1) uses a sealed single-row intermediate-shaft bearing that sits inside the M96 engine. Because the bearing is lubricated only by engine oil mist—not pressurized oil—it can slowly lose grease or develop micro-pitting. Once the bearing starts to fail you may hear a light metallic rattle at idle, find shiny metal debris on the magnetic drain plug, or see low oil pressure; left alone it can seize, break the shaft, and send debris through the engine—often requiring a full rebuild.

Most owners budget $2,500–$4,000 for a proactive IMS Retrofit (LN Engineering or Flat 6 Innovations kit) with rear-main-seal and clutch work while the gearbox is off. Waiting until after a failure can push repair bills well past $10k or even require an engine replacement.

Good news: a preventative bearing swap plus regular oil analysis keeps these engines reliable for the long haul. Would you like help finding local shops that specialize in IMS retrofits, or want to see similar 996 Coupes that already have the upgrade done?

Lot P626535: 1999 Porsche 911 Carrera

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Lot P626535: 1999 Porsche 911 Carrera

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