An engine’s front and back are traversed by a geared shaft called the Porsche IMS, or intermediate shaft. By means of the crankshaft’s mechanical revolution, it indirectly drives the camshafts on either side of the engine. The issue was not with the shaft itself. Since the 911 has existed, the shaft design has been used, and it has been successful as a component of the flat-six engines for which the Porsche is famous. However, the sealed cartridge-style ball bearings that support the IMS were the source of the IMS issue that existed previous until 2009.
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How much will it cost to replace my Porsche’s IMS bearing?
bearing replaced. The actual replacement of the ims bearing will take 10–14 hours.
To separate the engine and transmission, the engine and transmission must be dropped.
to have the IMS bearing changed. There are other more things that should be considered as well.
For a Bearing, $20,000?
Although a high-quality replacement improved IMS bearing does not cost “$20,000,” failing to do so could easily necessitate a significant engine repair or rebuild for your 911 or Boxster, which could cost more than $20,000.
Porsche 911s and Boxsters are an exceptional blend of power, usability, and top-notch German engineering. Because of its reputation as one of the highest caliber automakers, Porsche is adored all over the world. Even when Porsche automobiles have mileage that is up to 2-3 times that of their direct competitors, they nonetheless maintain an exceptional resale value. It is not unusual to find a contemporary water-cooled daily-driven 911 on the market with 150,000km or more with routine maintenance by a Porsche specialist.
Like other vehicles, 911s and Boxsters require special maintenance that must be done with great care. For Porsche, this includes the Intermediate Shaft Bearing, sometimes known as the “IMS” bearing.
Most of us Porsche owners have heard of the IMS bearing, but what is it and why are we interested in it? In essence, it’s a bearing in the back of the engine that needs the transmission to be removed in order to access. We don’t want to get into all of the “since you’re in there, let’s replace more” components, but there are quite a few of them. The two most important ones are that a clutch replacement and a rear main seal replacement can frequently be done simultaneously with an IMS retrofit installation at a low additional labor cost.
The IMS problem primarily affects years 1999 through 2005.
5 Porsche 911 and Boxster models with early M97 and M96 engines. Owners of turbos are not required to apply. In your autos, this problem is not present.
Returning to the IMS bearing now. The intermediate shaft’s main function is to use the crankshaft as an indirect drive for the camshafts. By using an intermediate shaft, the speed of the chains is decreased, improving chain life and the durability of all related components. The six-cylinder aircooled Mezger Porsche engine was built using this fundamental concept from its inception until 1998. The horizontally opposed flat 6 engine that Porsche uses has come to rely heavily on the addition of an intermediate shaft, which powers the camshafts indirectly off the crankshaft.
A dual-row ball bearing was used into the first IMS design, which was in service until 1999. (and included some 2000 and 2001 Boxster models). Porsche started to phase out the dual row bearing in late 1999 and switched to a single row bearing that was smaller but had a much lower load capability. All Porsche 911 models manufactured between 1999 and 2005.5 should have the single row OEM bearing replaced with our improved IMS bearing. The design was once more altered beginning with the 2006 model year to utilize a significantly larger single row bearing with a load capacity equivalent to the early dual-row IMS bearings. For 911 vehicles manufactured from 2006 to 2008, the factory-installed “grease seal” may need to be removed even though the IMS bearing does not need to be replaced. This makes it easier for the bearing to have enough lubrication to ensure a long life. The transmission must be removed in order to remove the grease seal, which is frequently done when the clutch and rear main seal are replaced.
Porsche Single-Row IMS Bearing Is Shown, and Special Installation Tools Are Needed
IMS bearing problem with Porsche explained
Porsche’s intermediate shaft bearing was one component of the new engine. This bearing, according to Autohaus Hamilton, uses chains to connect the engine’s crankshaft and camshafts. This prevents the chains’ lifespan from being significantly shortened when the crankshaft drives the camshafts. According to Car Throttle, the oil pump for the engine can also be driven by the crankshaft. Even air-cooled 911s have these shafts, according to RPM Specialist Cars. The component itself is not extraordinary.
But as Jalopnik noted, the Porsche IMS bearing has a defect in its design, which RPM Specialist Cars claims is related to the switch to water-cooling. The oil pump was assisted by the IMS, but there was no means for oil to lubricate it. It was forced to rely on the internal grease it already possessed. The grease would wear away and degrade with time. After then, its failure was only a matter of time.
Additionally, you would need to acquire a new engine for your 996 911 if it failed and you didn’t notice it in time. The 996 is often the least expensive 911 model because the Porsche IMS bearing problem is still a problem.
Porsche used a dual row intermediate shaft bearing from 1997 to 1999, and this bearing has proven to be just as durable as the larger single row used from model years 2006 through 2008. According to the IMS Class Action Lawsuit brought against Porsche, the Dual Row produced in-house was far more robust than the Single Row utilized from 2000 to 2005.
Porsche started phase-out of the dual row bearing in 2000 and switched to a smaller single row bearing with a much lower load capability. All engines used this smaller intermediate shaft bearing from 2002 through 2005, but for the 2006 model year, they switched to the larger third revision, which restored the load capacity to that of the original dual row bearing. The larger bearing for model years 2006 and later also had a larger diameter, which improved the bearing by increasing the bearing and ball speed. The IMS failure concerns have not entirely been resolved despite this adjustment, though.
Paul Kramer’s The Truth About the IMS Bearing
Not to pick on, but the 2009 model year marks a change in that Porsche fully did away with the IMS bearing. Although the IMS bearing was not completely abolished by the 2006-20008 (with the exception of a few very early model years that still had the leftover M96 engine), the failure of the bearing was essentially eradicated. I sincerely doubt that I have read about a single instance of an IMS failure on an M97 motor. It’s interesting to note that IMS bearings have been used in Porsche engines since the 996s. Every 911 from 1964 to 2008 had an IMS bearing, in actuality. Even the cherished Mezger automobiles, such as the Turbos and GT3s, lacked IMS bearings. They simply never fell short. The M96 motors’ failure was mostly the result of poor upkeep. It’s true that poorly designed seals permitted bearing failure in vehicles with little mileage and irregular oil changes. I have never saw an IMS bearing fail in a vehicle that was frequently driven and received regular/appropriate oil maintenance (at least once a year).
With Dwain Dement (the owner of Vision Motorsports), I had a lengthy conversation on the M97, M96, and 2009 direct injection motors. I even went on a tour of his engine manufacturing facility. Each year, Dwain produces around 100 M96 engines as well as almost as many M97 race motors. The IMS bearing is a genuinely trivial problem, which is funny. Any wear issues can be easily detected WELL before catastrophic failure with the right maintenance, etc. However, the majority of individuals simply follow the lore that is widespread online. The casting of the cylinders into the casing is the major problem with M96 motors that is frequently disregarded. They may crack with prolonged use or high mileage. Since their cases are thicker, M97 motors rarely experience cracking problems. According to Dwain, he has never witnessed an M97 motor’s IMS bearing fail. He claimed that the bearing is considerably bigger and stronger.
The M97 IMS failure rate is interestingly close to zero…even with rather subpar care. Additionally, due to how much larger the bearing is than its predecessor, it cannot be replaced until the engine case is opened. Since they are better for higher RPM and a little more durable than direct injection motors in terms of boring to bigger displacement, etc., Dwain employs the M97 motor for the majority of his race car engines. After each race, he conducts an oil study on every M97 engine he supports (well over 20-cars). It’s interesting to note that he rarely observes excessive metal wear until there has been a serious missed shift, which he notes using the Motec(r) system, which is far more accurate than the original DME.
Sorry for the rant, but I’ve written numerous articles about it, visited four engine shops, and spoken with a ton of mechanics and engine builders, including Dwain, Deiter (Andial), Tony Callas, and others. There are numerous misconceptions regarding IMS bearings, etc. I went directly to folks who see these motors and bearings on a daily basis rather than depending on what is written online or in magazines.
Personally, I believe that direct injection motors are given far too much credit. Think about all the troubles that VW and BMW are experiencing with that configuration. All day long, I would choose an M97 engine to save money.
Porsche stopped utilizing the IMS bearing in what year?
The IMS (middle shaft) of an M96 or M97 engine is supported by a sealed ball bearing. the bearing installed on the intermediate shaft by
Porsche offers an interval, replacement process, or replacement IMS bearing for
It was not able to replace or upgrade the original factory IMS bearing until LN Engineering.
inquiries to find out all there is to know about intermediate shaft bearings
and why the best IMS bearing Retrofit and Solution products are those made by LN Engineering
How much does a Porsche 911’s IMS bearing cost to replace?
Thousands of independent technicians advocate IMS Retrofit ceramic hybrid ball bearing as the best preventive treatment because it is the only long-term fix for IMS bearing issues in M96/M97 engines. IMS Retrofit replacement bearings typically cost more than $4,000 in labor and materials, but they can be installed at the same time as the clutch. Compared to the price of rebuilding or replacing the entire engine, this is a relatively low expenditure. The cost of this repair should be weighed against the minimal likelihood that an IMS breakdown will occur in an older Porsche. You might decide it is worth the risk if you carefully evaluate the possibility of a future failure and compare it to the cost of an IMS Retrofit bearing. This preventative procedure, however, may very well be a worthwhile outlay to avoid future harm and larger spending in the future if you are worried about the health and well-being of your Porsche.
Which model Porsche 911 is having an IMS issue?
The intermediate shaft bearing, commonly known as an IMS bearing, has a significant failure rate in the Porsche 911 and Porsche Boxster from model years 1997 to 2005. Its build and design cause the bearing to prematurely fail, which causes a catastrophic engine failure.
Should my IMS bearing be replaced?
Any IMS bearing replacement is meant to be installed as a proactive step in routine maintenance and preventative care. The replacement of the intermediate shaft bearing is no longer an option once an engine has failed.