Porsche IMS Bearing - What cars have it?
Here's a detailed guide to help you identify which Porsche models feature the IMS bearing and the specific type of bearing they use. It's important to note that due to engine updates, some models straddle the transition between different types of IMS bearings. This change primarily took place between 2000 and 2001. Because of these updates, determining the type of IMS bearing solely by the model year is unreliable. A more accurate method is to identify it by the engine number, as outlined below.
- 1999-2001: Features a Dual Row IMS bearing up to Engine #661 14164.
- From 2000 onward: Equipped with a single-row IMS bearing starting from Engine #661 14165.
Dual Row Engines
- Valid up to Engine #671 11237 (M96.21)
- Valid up to Engine #651 12851 (M96.22)
Single Row Engines
- Starting from Engine #671 11238 (M96.21)
- Starting from Engine #651 12852 (M96.22)
Permanent Single Row Bearings
- The permanent single bearings were introduced in 2005 for both the 911 and Boxster models. As of now, the only definitive way to identify the type of IMS flange in these vehicles is by removing the transmission and conducting a hands-on inspection of the engine.
By using engine numbers as your reference, you can more precisely identify the type of IMS bearing in your Porsche, which is crucial for proper maintenance and potential replacement.
What should I know about the IMS Bearing?
During the Eisen Class Action lawsuit, it was revealed that single row Porsche IMS bearings had an 8% failure rate, while their dual row counterparts had only a 1% failure rate. Despite some misconceptions that these bearings become more reliable as Porsche Boxster, Cayman, and 911 engines age, evidence suggests the contrary: the likelihood of a Porsche IMS bearing failing actually increases over time. So, if you haven't encountered an IMS bearing failure in your Porsche yet, that doesn't eliminate the need for future replacement. The Porsche IMS bearing is a consumable part that should be routinely swapped out, especially in Boxster and 911 996 models where the bearing is serviceable. We offer various solutions to address this issue, along with insights into why we think these failures occur
Versions of the bearing -
Three variations of bearings exist: the dual-row type, found in early model engines; the single-row version, appearing in engines from 2000-2001; and the larger, non-serviceable single-row bearing that started to emerge in engines from late 2005 onward. For the 2005 models, some engines feature the serviceable single-row bearing while others have the larger, non-serviceable version. Though the latter is not designed to be serviceable, aftermarket solutions are available that allow servicing. However, these solutions often require modifications to the IMS bore to enable extraction without taking apart the engine.
Other General Information on the Porsche IMS Bearing -
Initially, ball bearings were selected for the Porsche IMS bearing due to their balanced handling of both axial and thrust loads. While roller bearings are prevalent in car gearboxes, they typically only manage about 10% of their total load capacity in thrust, compared to 50% for ball bearings. Additionally, roller bearings usually handle thrust in one direction, often requiring pairing with a ball bearing for balanced thrust control.
Porsches from the 2006 model year onwards, including 911 997, Boxster, and Cayman models, come equipped with an IMS bearing that's non-serviceable without a full engine disassembly.
When it comes to replacement engines, they will feature the type of IMS bearing that was standard during that model year. Engines replaced after 2006 will also possess the non-serviceable, larger IMS bearing.
Nearly ten years after the release of the IMS Retrofit, Porsche released their own IMS bearing upgrade kit in 2017. This kit uses a ceramic hybrid ball bearing, similar to the IMS Retrofit.
Once an IMS bearing fails, it can't be replaced; the intermediate shaft can also be damaged, and metallic particles can circulate throughout the engine.
The dual-row bearings used in specific IMS Retrofit solutions have load ratings comparable to similar-sized cylindrical roller bearings designed for IMS. Contrary to claims by some competitors, these cylindrical roller bearings can handle both fore and aft thrust loads and serve as a suitable ceramic hybrid ball bearing alternative.
The M96/M97 engine features a wet sump system, meaning the intermediate shaft is immersed in oil, lubricating the IMS bearing. This eliminates the need for a direct or forced oiling system. Ceramic hybrid ball bearings require less lubrication, needing only a small amount of oil for effective functioning.
A permanent solution exists that modifies your Porsche's IMS to function like the oil pressure-fed plain bearings in both air-cooled and water-cooled Mezger engines. This solution uses a patented filter adapter and an external oil line to feed oil to a plain bearing, offering a no-fail mechanism.
Since 2008, over 40,000 IMS bearing replacement kits have been successfully installed worldwide in Porsche Boxster and 911 996 models. No reported failures have occurred when qualified installations have been made, whether using dual-row ceramic hybrid or cylindrical roller bearings, or the oil pressure-fed plain bearing.
How Do I know if my IMS Bearing is failing?
Often, the initial indicator of a failing IMS bearing is severe engine damage, making early detection crucial. Porsche's original sealed ball bearing keeps the wear debris confined within itself until it's near total failure. When the grease seal on the bearing eventually deteriorates, this debris escapes and gets caught in the oil filter, appearing like metallic glitter. If you run a magnet through the filter media, it will pick up these metallic particles. Importantly, the single-row bearing in models from 2000-2005 can suddenly fail without emitting any visible debris, unlike the dual-row bearing, which often releases wear particles for several thousand miles before total failure.
Some owners rely on used oil analyses and filter checks to assess the condition of their IMS bearings. However, this method can be deceptive. Such analyses cannot detect IMS debris, as the particle size is larger than the detection threshold. Similarly, a clean oil filter doesn't necessarily imply that the IMS bearing is in good condition; it can deteriorate rapidly without any signs.
The advisable course of action is proactively replacing the IMS bearing as a part of regular maintenance, even for engines with already replaced ball or roller bearing IMS units. These are all wear-and-tear parts, with the exception of specialized solutions that convert the problematic IMS bearing to an oil-fed plain bearing similar to those found in Mezger engines.
How To Reduce The Risk of Porsche Intermediate Shaft Bearing Failure?
Firstly, it's important to note that not using your Porsche as intended can exacerbate the issue. The consensus among specialists is that frequent oil changes using high-quality 5W40 motor oil, such as MOTUL 8100 X-CESS, every 6 months or at 5,000-mile intervals can be an effective preventive measure. Moreover, driving your Porsche regularly and keeping the RPMs between 2500 and 3000, especially by avoiding higher gears, may also contribute to prolonging the lifespan of the ball-bearing in the intermediate shaft. Vehicles with lower mileage that have infrequent oil changes and are not driven energetically (i.e., at low RPMs) are generally more susceptible to failure.
Alongside consistent oil changes, installing a magnetic drain plug and closely inspecting the oil filter and magnet during these shorter intervals could aid in early detection of potential issues. However, later models with the single-row bearing can still fail suddenly. Ferromagnetic particles from a deteriorating intermediate shaft bearing may be evident in the filter, appearing similar to silver glitter. If you find larger debris, it usually signifies a complete failure. Using a Spin-On Filter Adapter can help in preventing these particles from causing additional engine damage by eliminating bypass routes. When this adapter is used in conjunction with the Oil Filter Magnet, a filter cutter should be employed for thorough inspection. As a general rule, replacing the IMS bearing as part of your routine maintenance schedule is advisable. The oil-fed plain bearing is often considered the most effective method for preventing IMS bearing failures.
What are my options to fix my IMS Bearing?
Porsche IMS Bearing Replacement
At HBi Auto, our expertise in Porsche vehicles allows us to provide tailored advice to each client on whether their car requires an IMS bearing replacement and which type would be most suitable. Understanding that the IMS bearing can be a complex issue, we offer comprehensive evaluations using the latest diagnostic tools to assess the current condition of your vehicle's bearing. Once assessed, we'll discuss the various IMS bearing solutions available, helping you make an informed decision that aligns with your driving habits and the longevity of your vehicle. Our goal is to ensure your Porsche is maintained at the highest standard, providing you with peace of mind on the road.We pride ourselves on serving a broad range of locations, catering to major cities and offering an array of value-added services to make your experience as convenient as possible. Our complimentary enclosed transport ensures that your Porsche arrives safely at our facility, no matter your location. Once it's here, we offer a free alignment check, complimentary inspection, and free diagnostics with repair. Additionally, your vehicle will receive a complimentary detail to have it looking as impeccable as it performs. All of our repair and replacement work is backed by our 24,000-mile/24-month warranty, cementing our commitment to quality and customer satisfaction. Reach out to one of our specialists today to discover the best IMS bearing solution for your Porsche.