Service intervals – Quick Guide


Why are there recommended service intervals for Porsche IMS bearings?

The factory did not originally offer any replacement IMS bearings for the intermediate shaft nor did they offer tools, a procedure to change out the IMS bearing, or even a service interval for the original bearing.

We all know that load capacity is the primary issue with the single row 6204 bearing and that the failure rate is significantly reduced with the dual row bearing by virtue that the dual row has twice the load capacity and that having a grease seal on the original bearing greatly reduced lubrication of the original bearing. That said, we all know that cars that were infrequently driven, poorly maintained, or driven short distances, especially in cold climates, are more likely to suffer an IMS failure.

One reason we mandate service intervals based on time or mileage, whichever comes first, is that contamination of the bearing lubricant (IE your engine oil) by water or moisture as well as by combustion byproducts significantly reduces the bearing life. In fact, as little as 0.002% water will reduce bearing life by 48% and 6% water content reduces bearing life by a whopping 83%* (figures quoted by the McNally Institute). So letting your car sit really is one of the worst things you can do for it, especially your IMS bearing. And regardless of whether you use a ball or roller bearing, contamination in your oil leading to corrosive wear will reduce the service life for any replacement IMS bearing, with exception of the IMS Solution.

The choice of lubricant also has a huge effect on the life of your replacement IMS bearing. A40 oils have reduced levels of ZDDP anti-wear additives and most have only trace amounts of active EP additives such as moly, both of which directly affect bearing wear. The additive package is even more important for your IMS bearing as the typical 0w40 oil will have a viscosity at 100 deg C of 12.9 cSt which is significantly lower than what most bearing manufacturers recommend for lubricant viscosity for a ball or roller bearing of 15 cSt. Those running Driven DT40 should have reduced wear and longer useable life for their replacement IMS bearing than anyone running any Porsche A40 approved oil and use of Driven FR50 or DT50 will provide superior protection given they have a typical viscosity index over 17 cSt @ 100 deg C.

IMS Retrofit™

4 years or 50,000 miles

IMS Retrofit™
Dual Row

6 years or 75,000 miles

IMS Retrofit™
Single Row Pro

6 years or 75,000 miles

IMS Retrofit™
MY 06-08

6 years or 75,000 miles

IMS Retrofit

6 years or 75,000 miles

IMS Solution
All kits

Life of the engine

Triple Row
IMS Upgrade

6 years or 75,000 miles

Pelican Parts

3 years or 36,000 miles

“Cleanliness is next to Godliness.”

The same rule applies to your engine. Long drain intervals kill engines as does inferior engines oils. Once you have installed an IMS Retrofit or IMS Solution bearing in your engine, the cleanliness and quality of your engine oil will directly affect bearing life.

To maximize bearing life, the correct oil filter and engine oil needs to be used. We only recommend use of Joe Gibbs Racing Driven BR Break-in and DT40 engine oils.

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. Use of the LN Engineering Spin-On Oil Filter adapter by design prevents any oil from bypassing the filter, so 100% of the oil gets filtered 100% of the time and is recommended for every M96 engine.

The IMS Solution comes standard with a Spin-On Oil Filter adapter, which provides superior engine oil filtration and it makes oil changes easier, which is an added bonus.

Recommended Service Intervals

The IMS Solution is designed to last the lifetime of the engine and does not have a service interval.

The Dual Row IMS Retrofit™ and Single Row Pro IMS Retrofit™ both have a 6 yr or 75,000 mile service interval. The RND Roller Kits have a 4 yr or 50,000 mile service interval.

Service interval recommendations are valid only with use of Joe Gibbs BR break in oil during the new IMS bearing break-in period of 200-400 miles along with use of an LN Engineering Spin-On Oil Filter Adapter with subsequent oil changes at 6 months or 5,000 miles using Joe Gibbs DT40. Severe service interval is 3 months or 3,000 miles.

Track use requires use of a race oil with more frequent change intervals due to lower levels of detergents and corrosive inhibitors in race oils.

The Classic Single Row IMS Retrofit has a 4 yr or 50,000 mile service interval; as the last Classic Single Row IMS Retrofit was manufactured and sold in 2014, it is safe to say that every Classic Single Row IMS Retrofit bearing is past the original service interval and past due for replacement. Replacement is recommended at time of clutch service and upgrading to the new Single Row Pro IMS Retrofit or IMS Solution is recommended. If upgrading to an IMS Solution, please note that the replacement snap ring originally supplied with the PEL-IMS-1, Classic Single Row IMS Retrofit, and the single row RND RS Roller kits is not compatible with the IMS Solution; we have a limited number of original clips that we can supply if requested.

If your engine was rebuilt prior to 2014 and fitted with our Triple Row IMS Upgrade, this product was superseded by the Single Row Pro IMS Retrofit and the IMS Solution. All Triple Row upgrades are past their service interval and are due for replacement. Please contact LN Engineering for more information on your available upgrade choices for the Triple Row IMS Upgrade.

The posted service interval for the Pelican IMS-PEL-1 was determined by Pelican Parts and is listed for reference purposes only; LN Engineering does not sell or support this product.

Refer to the table below to approximate installation date (+ / – 6 months) based on the serial number ranges.

Serial Number Production Date
2000 April 2011
5000 April 2012
9000 April 2013
12000 April 2014
17000 April 2015
22000 April 2016
25500 April 2017
28000 April 2018
31000 April 2019
33000 April 2020
36000 April 2021
39000 April 2022