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Message: IMS Failure Root Causes
Changed By: thom4782
Change Date: July 03, 2013 12:13PM
IMS Failure Root Causes
Change Date: July 03, 2013 12:13PM
IMS Failure Root Causes
This is my understanding of the root cause of Boxster IMS failures.
SWhen bearing seals degrade, small amounts of oil enter the bearing and mix with the bearing grease when the bearing seals degrade. . When this happens, the oil-grease mixture loses the ability to lubricate adequately and the bearings fail from friction.
How does this relate to driving style. The answer is indirectly. Seals degrade when they sit in contaminated oil for extended periods. This happens to all cars if the oil isn't changed frequently. It also happens to low mileage cars because the lower halfs of the bearing seals sit in acid / moisture ladened oil for long periods when the car is garaged for extended periods. It can also happen to more frequently driven cars that take short trips where the moisture doesn't get a chance to evaporate because the oil doesn't get hot enough for a long enough period of time. For these reasons, low mileage cars regardless of oil change frequency and cars with long oil change intervals tend to experience more IMS failures.
IMHO the best advice for extending the IMS bearing life is this. Change oil frequently (say every 5000 miles or every year whichever comes sooner). Drive the car often at operating temperatures for 30 minute periods or longer. Don't let the engine lug or run at low rpms to avoid high side loading of the bearings.
BTW: the ceramic retrofit bearings avoid the OEM bearing problems in two ways. One, ceramic bearing just last longer than steel ones. Two, ceramic bearings like the LN Retrofit are unsealed and don't face the mixed lubrication problem that the OEM bearing with a degraded seal does
SWhen bearing seals degrade, small amounts of oil enter the bearing and mix with the bearing grease when the bearing seals degrade. . When this happens, the oil-grease mixture loses the ability to lubricate adequately and the bearings fail from friction.
How does this relate to driving style. The answer is indirectly. Seals degrade when they sit in contaminated oil for extended periods. This happens to all cars if the oil isn't changed frequently. It also happens to low mileage cars because the lower halfs of the bearing seals sit in acid / moisture ladened oil for long periods when the car is garaged for extended periods. It can also happen to more frequently driven cars that take short trips where the moisture doesn't get a chance to evaporate because the oil doesn't get hot enough for a long enough period of time. For these reasons, low mileage cars regardless of oil change frequency and cars with long oil change intervals tend to experience more IMS failures.
IMHO the best advice for extending the IMS bearing life is this. Change oil frequently (say every 5000 miles or every year whichever comes sooner). Drive the car often at operating temperatures for 30 minute periods or longer. Don't let the engine lug or run at low rpms to avoid high side loading of the bearings.
BTW: the ceramic retrofit bearings avoid the OEM bearing problems in two ways. One, ceramic bearing just last longer than steel ones. Two, ceramic bearings like the LN Retrofit are unsealed and don't face the mixed lubrication problem that the OEM bearing with a degraded seal does
Original Message
Author: thom4782Date: July 03, 2013 12:09PM
IMS Failure Root Causes
This is my understanding of the root cause of Boxster IMS failures.
Small amounts of oil enter the bearing and mix with the bearing grease when the bearing seals degrade. When this happens, the mixture loses the ability to lubricate and the bearings fail from friction.
How does this relate to driving style. The answer is indirectly. Seals degrade when they sit in contaminated oil for extended periods. This happens to all cars if the oil isn't changed frequently. It also happens to low mileage cars because the lower halfs of the bearing seals sit in acid / moisture ladened oil for long periods when the car is garaged for extended periods. It can also happen to more frequently driven cars that take short trips where the moisture doesn't get a chance to evaporate because the oil doesn't get hot enough for a long enough period of time. For these reasons, low mileage cars regardless of oil change frequency and cars with long oil change intervals tend to experience more IMS failures.
IMHO the best advice for extending the IMS bearing life is this. Change oil frequently (say every 5000 miles or every year whichever comes sooner). Drive the car often at operating temperatures for 30 minute periods or longer. Don't let the engine lug or run at low rpms to avoid high side loading of the bearings.
BTW: the ceramic retrofit bearings avoid the OEM bearing problems in two ways. One, ceramic bearing just last longer than steel ones. Two, ceramic bearings like the LN Retrofit are unsealed and don't face the mixed lubrication problem that the OEM bearing with a degraded seal does
Small amounts of oil enter the bearing and mix with the bearing grease when the bearing seals degrade. When this happens, the mixture loses the ability to lubricate and the bearings fail from friction.
How does this relate to driving style. The answer is indirectly. Seals degrade when they sit in contaminated oil for extended periods. This happens to all cars if the oil isn't changed frequently. It also happens to low mileage cars because the lower halfs of the bearing seals sit in acid / moisture ladened oil for long periods when the car is garaged for extended periods. It can also happen to more frequently driven cars that take short trips where the moisture doesn't get a chance to evaporate because the oil doesn't get hot enough for a long enough period of time. For these reasons, low mileage cars regardless of oil change frequency and cars with long oil change intervals tend to experience more IMS failures.
IMHO the best advice for extending the IMS bearing life is this. Change oil frequently (say every 5000 miles or every year whichever comes sooner). Drive the car often at operating temperatures for 30 minute periods or longer. Don't let the engine lug or run at low rpms to avoid high side loading of the bearings.
BTW: the ceramic retrofit bearings avoid the OEM bearing problems in two ways. One, ceramic bearing just last longer than steel ones. Two, ceramic bearings like the LN Retrofit are unsealed and don't face the mixed lubrication problem that the OEM bearing with a degraded seal does