First of all, there’s no need to loose sleep over IMS failures! The best preventative measures that can be taken are to be religious with your maintenance schedule. But keep reading, there’s more that you can do.
So what can be done to minimize the likelihood of an IMS failure?
Although a greatly debated subject, most experts agree that more frequent oil changes every 6 months or 5,000 miles is a good first step. If you drive short distances frequently or in cold climates, more frequent changes every 3,000 miles or 3 months is advisable. One of the most common sources of trouble in bearings is wear and pitting caused by foreign particles and is responsible for 70% of all early bearing failures. As the IMS Retrofit employs an open bearing and is lubricated by engine oil in the crankcase, filtration is even more important. We use factory Mann, Mahle, or Hengst oil filters because of their high quality standards.
Secondly, use of premium engine oil such as Total Quartz 5w40 (which is a Porsche approved oil) can also provide added protection to all critical engine components. By no means should you use any oil thinner than a 0w40 – do not use 0w30, 5w30, or 10w30 viscosities! Also, use of low SAPS oil (has less Zn and P) isn’t recommended.
Lastly, actually driving your Porsche more often and avoiding higher gears in order to keep the revs above 2500-3000 rpm is another good step to take to improve the life of the ball-bearing in the intermediate shaft (the faster you spin the IMS bearing, the longer it will last and less it will wear). Although there is limited data, the general trend is that lower mileage vehicles with infrequent oil changes or driven light-footed (as in run at low speed/engine rpms) are most likely to suffer a failure rather than those cars that are driven hard and well-maintained.
Along with more frequent oil changes, the addition of a magnetic drain plug coupled with close inspection of the oil filter and magnet at these shorter intervals may help owners identify a failure in its early stages, but later models using the single row bearing can fail with little warning. When inspecting the filter and magnetic drain plug, ferromagnetic debris from the intermediate shaft bearing can be identified easily, appearing like silver glitter. Larger debris than this is indicative of a complete failure. With proper lubrication, more frequent oil changes, and spirited driving, longevity of your original IMS can be greatly extended.
For those with MY06-08 intermediate shafts that cannot have their bearings replaced, we recommend to remove the grease seal from the existing ball bearing, which allows for engine oil to lubricate the bearing, but only when doing another procedure like a clutch, flywheel, or rear main seal replacement.
Timing is everything. If you wait too long, a catastrophic failure may preclude the ability to replace your IMS bearing with an IMS Retrofit™ kit. Remember, often there is little warning of an impending IMS failure. Bare minimum, you need add a magnetic drain plug. This makes for easy inspection for IMS debris at time of performing an oil change.
Any oil leaks at the rear of the engine should be checked out immediately – it is common to think you have a RMS leak, but in fact, a failing bearing can cause the IMS flange seal to leak.
Lastly, any technician who knows what a failing water pump or idler belt bearing sounds like should be able to use a stethoscope to listen to the IMS for similar problems from the general vicinity of the IMS bearing. If there is any noise that may be IMS related, remove the serpentine belt to isolate idler pulleys, power steering pump, alternator, and even water pump noise.