The IMS bearing is the best-known weak point of water-cooled Porsches from 1997 to 2008. It supports the intermediate shaft, which drives the camshafts from the crankshaft. If the bearing fails, debris spreads through the engine, and the usual result is a full rebuild or a replacement engine.
The risk is real but often overstated. Most cars never fail, and there's a well-proven fix. If you're buying or selling one of these cars, what matters is knowing which bearing the car has and whether it has been replaced.
Key numbers
- Years affected
- 1997–2008 Boxster, Cayman and 911 models with the M96 or M97 engine.
- Highest risk
- The single-row bearing used from 2000 to 2005, with an 8% failure rate documented in a class action.
- Replacement cost
- About $2,000–$5,000 installed, depending on the kit, per Renn Driver.
- Not affected
- Turbo, GT2 and GT3 models, and all 911s from 2009 on.
Which Porsches have the IMS bearing problem
| Model years | Bearing | What to know |
|---|---|---|
| 1997–1999 | Dual-row | The more durable early design. Can be replaced with the engine in the car. |
| 2000–2005 | Single-row | The most failure-prone. An 8% failure rate was documented in the class action settlement. |
| 2006–2008 | Larger, non-serviceable | Stronger, but can't be replaced without taking the engine apart. |
Bearing types and the failure rate as published by LN Engineering, which makes the best-known replacement bearings. Some model years overlap, so confirm which bearing a specific car has.
These engines were fitted to the Boxster (986 and 987), the Cayman (2006–2008) and the 911 Carrera (996 and 997.1).
Not affected: the 996 and 997.1 Turbo, GT2 and GT3, which use the separate Mezger engine, and every 911 from 2009 on, which uses a newer engine with no IMS bearing.
Warning signs of a failing bearing
- Metal in the oil. Fine metallic debris, described by LN Engineering as looking like silver glitter, on the drain plug or in the oil filter.
- An oil leak at the back of the engine. It can come from the bearing's support stud or seal.
- A new knocking or rattling noise from the rear of the engine.
Often there's little warning, which is why owners replace the bearing preventively. Regular oil changes with filter inspection are the best early check.
IMS bearing replacement cost
| Option | Installed cost |
|---|---|
| Classic retrofit bearing | $2,000–$3,500 |
| Pro retrofit bearing | $2,500–$4,000 |
| IMS Solution (permanent) | $3,500–$5,000 |
| Retrofit plus new clutch | $4,000–$6,500 |
Estimates published by Renn Driver, checked October 2026. Prices vary by shop and region.
The transmission has to come out to reach the bearing, so most owners have the clutch replaced at the same time. Retrofit bearings have a recommended service interval of six years or 75,000 miles, according to LN Engineering. The IMS Solution replaces the ball bearing with an oil-fed plain bearing and is designed to last the life of the engine.
The 2006–2008 bearing can't be changed this way, because the engine has to be taken apart to reach it.
What it means when you sell
Buyers of 1997–2008 cars will ask about the IMS bearing before almost anything else. A receipt for a retrofit from a recognized shop removes the biggest objection and supports a stronger offer. Without one, expect buyers to price in the cost of the job.
Keep the invoice with the car's records. See the 911 seller's guide and the Boxster and Cayman guide for what else buyers check.
Common questions
What years did Porsche have the IMS bearing problem?
Model years 1997 to 2008, in Boxster, Cayman and 911 Carrera models with the M96 or M97 engine. The single-row bearing used from 2000 to 2005 is the most failure-prone.
How much does IMS bearing replacement cost?
Renn Driver estimates $2,000 to $5,000 installed, depending on the bearing kit, or $4,000 to $6,500 when combined with a new clutch.
How likely is an IMS bearing to fail?
For the 2000–2005 single-row bearing, an 8% failure rate was documented in the class action settlement. The earlier dual-row and later large bearings fail far less often.
Do Porsche 911 Turbo and GT3 models have an IMS bearing problem?
No. The 996 and 997.1 Turbo, GT2 and GT3 use the Mezger engine, which doesn't have this issue.
Should I replace the IMS bearing before selling?
If the clutch is due anyway, doing both together can make the car easier to sell. Otherwise, get a quote and compare it with what buyers would deduct.
Sources
- LN Engineering: IMS 101
- LN Engineering: IMS bearing problem years
- Renn Driver: Porsche IMS bearing guide
Figures were checked against these sources in October 2026. Prices change, so confirm before relying on them.