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. 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
In This Article...
Porsche IMS Bearing: Should It Be Replaced?
More of the Porsche 996 and 986 Boxster are changing hands as a result of their recent increase in popularity. An increase in sale price and a large number of purchasers seeking the security of a car with the IMS bearing changed come along with this increase in attraction. As a result, we are replacing one IMS bearing virtually every week in our workshop right now. So how likely is it that your Porsche’s IMS Bearing (Intermediate Shaft Bearing) will fail catastrophically and cause an engine failure? The failure rate is expected to be around 4% for the Boxster 986 and Model 996 from 1998 to 2005, which are the models most prone to this problem. In light of this, Stu does advise replacing the IMS bearing in some versions for added security. The decision is far more difficult for other less vulnerable types.
The following models are vulnerable to IMS failure:
Many people believe it’s better to be safe than sorry, especially if you own one of these devices, because there is sadly no pattern to when IMS failure happens and there are few warning indications. Failure can occur at any time over the lifespan of the car, even after 100,000 miles. In our experience, the majority of purchasers demand that the bearing has been changed or, alternatively, factor its replacement cost into the purchase discussions if you’re preparing to buy or sell one of these models.
There are a few choices for IMS bearing replacement. The price varies based on the replacement parts you select and whether your vehicle is a manual or automatic. The prices listed here apply to the most vulnerable 996 and Boxster models from 1998 to 2005.
Option 2: Replace the oil-fed system
Unfortunately, by the time indications of IMS failure become visible, the damage may have have been done as there are few early warning indicators that may be recognized. Metal debris found in your oil and filter is the best sign that there is a problem. Oil seeping from the engine’s rear is another sign, and your engine may also start to knock. Even if you quickly stop driving the car once the engine starts to knock, the harm to the engine can already be done.
There are considerable savings of scale in changing your IMS bearing and clutch at the same time if you’re thinking about getting a new clutch but haven’t done so yet. Having both of these replacements done at once will save you a lot of money on labor as they both need the removal of the transmission.
If you own a 996 and are looking for additional Stuart-recommended improvements, you might want to click on this link to an earlier post. What’s on the menu? 996
THE CORRECTIVE
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.
When was the IMS bearing fixed by Porsche?
Following the release of the IMS Retrofit by LN Engineering in 2008, Porsche introduced their own IMS bearing replacement in 2017 using a sealed ceramic hybrid ball bearing.
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.
What does a Porsche IMS bearing mean?
IMS bearing failure is a problem that affects Porsche vehicles quite frequently. The intermediate shaft, which runs the length of the engine, is supported by the IMS bearing (also known as the intermediate shaft bearing). In most Porsches, the issue is not the actual intermediate shaft. The infamous engine issues that beset this antique automobile brand are caused by the IMS bearing.
The IMS bearing in your Porsche could break down from regular wear and tear. However, mechanical errors account for the majority of this feature’s failures. Due to their older designs, the Porsche models 986, 987, 996, and 997 are more vulnerable to IMS bearing failure.
Lack of lubrication causes the bearing to repeatedly overheat, which eventually leads to IMS bearing failure. The only real defense against this is to get your automobile serviced on a regular basis by qualified mechanics and to get an oil change every two years.
IMS bearing failure may not be completely preventable, but any mechanic with expertise in Porsches will be able to spot any little details that might point to this system malfunctioning. To avoid a complete failure, they will give you advice and make improvements while conducting inspections.
What year Porsches experience IMS issues?
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.
Which Porsche models are affected by IMS issues?
All Boxster, Cayman, and 911 vehicles from MY1997 to MY2008, with the exception of Turbo, GT2, and GT3 variants, are susceptible to IMS bearing failure.
But over time, the types of bearings utilized changed, and some of them were more likely to fail than others. According to statistics, the Boxster 986 and 911 models built between model years 2000 and 2005 are the most likely to experience IMS bearing failure, whereas the odds are extremely low for a Boxster 987 or Cayman built after a stronger bearing was introduced in late 2005.
In terms of mileage, there is no clear trend in the failures; some owners were unfortunate enough to encounter IMS issues at less than 20,000 miles, while others assumed they were safe only to have the bearing fail at 130,000 miles. In summary, you should be aware of potential issues if you now own or intend to purchase one of the versions with the weaker bearing that were in use from 2000 until late 2005.
The base engine (3.6) bears the designation “M96,” and depending on your engine number, you may have the smaller IMS or the revised bigger bearing:
Engine (3.6) number M96/05 69507476 has the larger updated IMS bearing, while Engine (3.6) number M96/05 69507475 has the smaller IMS bearing.
The “S” Engine (3.8) is designated “M97” and features a choice of a smaller or bigger upgraded IMS bearing:
Engine (3.8) numbers beginning with M97/01 68509791 have the larger updated IMS bearing, whereas Engine (3.8) numbers up to M97/01 68509790 have the previous IMS bearing.
How much does an oil change for a Porsche 911 cost?
Porsche 911 oil changes typically cost between $517 and $534. While parts are priced between $473 and $480, labor costs are predicted to range between $43 and $55. Taxes and other fees are not included in this range, nor are your particular model year or geographic area taken into account. Additional fixes could be required.