Philes’ Forum – Spring 2017


Trip Lee (1947 – 2017) – New Jersey Chapter Icon

The New Jersey Chapter, as well as humanity, suffered a great loss when Trip Lee passed away on 14 February. Trip was a unique, consummate gentleman of intellect and character, and I feel privileged to have known him for more than 30 years. If you are thinking I greatly respected and admired Trip, you are correct.

While some gearheads tend to be one-dimensional, Trip had varied interests, including history and aviation, in addition to his love of all things mechanical. One time he told me that as part of his study of the U.S. Civil War, he was reading soldiers’ letters written during the conflict. That’s some pretty serious study if ya ask me.

Trip and I would occasionally recommend books to each other. Our most recent correspondence, late in 2016, concerned a book about the closing months of WWII and how British airmen, at great cost, helped ameliorate the swarm of Kamikazes over the waters near Japan. The Brits did this by attacking Kamikaze airfields.

I can neither count nor recall all the times Trip helped me out, whether it was instructing novice-driver me at Lime Rock, mentoring me when I aspired to become a driver-school instructor, tactfully advising me when I became Chief-of-Tech for our driver schools, giving me lathe-operation pointers, or finding cool gearhead stuff for me or us. He once found a source in Germany and had imported two “dogleg” or “close-ratio” 5- speed transmissions, one for wife Judy’s M3 and one for mine. Trip found me a very nice, industrial-quality, [made in U.S.A., no less] floor-mount drill press that I use in my shop nearly every day. When Trip upgraded his TIG welder, I got his old one. One time he gave me a completely functional, 12” Clausing turret lathe.

I could continue, but knowing Trip, he would say, “Enough already; let’s get to the good stuff”. [But Trip would phrase it tactfully.] So Trip, if you are reading this, thanks, man.

The good stuff this month concerns BMW power-steering reservoirs. I looked in the Philes’ Forum archives, and the best I can tell I have not written on this subject in more than 10 years.

In January 2007 I was writing about oil filters, and I wrote that in addition to the oil filter, air filter, fuel filter, and cabin filter, your Bimmer also has a power-steering filter. This filter is located in the bottom of the powersteering- fluid reservoir, and unfortunately, unless your Bimmer is 40 or so years old, the filter is not replaceable without changing the reservoir.

Photo #1 depicts the power-steering reservoir found on many Bimmers from model year 1982 right up to much later models, such as the E84 X1 and E87 1-Series. Photo #2 shows a reservoir cut in half to reveal the internal filter. I think it a good idea to change the reservoir/filter whenever you do maintenance on the power-steering system such as changing the fluid, hoses, pump, or steering box. While you’re at it [actually, before you install any new parts], it’s also a good idea to flush out the system. The January 2007 Philes’ Forum [available on the NJ Chapter Website], describes one procedure for flushing the power-steering fluid.

Photo #1 – Ubiquitous Power Steering Reservoir
Photo #2 – Power Steering Filter Revealed

Driver-school Padrone Jeff White emailed me about his 2000 528i E39 5-Series touring [manual trans!]. Jeff is replacing the power-steering reservoir, and the replacement-reservoir’s cap indicates that Pentosin CHF 11.S fluid is required, and Jeff has been using Dexron-type automatictransmission fluid [ATF] as specified in his owner manual. Jeff was told by the aftermarket supplier of the new reservoir that Jeff needed to convert the system to CHF 11.S fluid, and Jeff questioned me on how to do this.

The current BMW part number for Jeff’s power-steering reservoir is 32 41 6 851 217. The only apparent difference between the current version and superseded versions [eg: 32 41 1 097 164] is that the cap on the current version specifies CHF 11.S fluid, not ATF. See Photo #3 [Courtesy of Jeff White].

Photo #3 – Cap From Current Replacement Reservoir
Photo by Jeff White

My response to Jeff is that the steering-system design, not the reservoir, is what determines which fluid is to be used, and that he should continue to use ATF in the E39’s power steering. Just to double-check, I contacted Matt Kimple, service manager at Bridgewater BMW, and he confirmed that IF YOUR BIMMER ORIGINALLY USED ATF IN ITS POWER-STEERING, DO NOT PUT CHF 11.S IN IT, REGARDLESS OF WHAT THE RESERVOIR CAP INDICATES. If you are in doubt about which fluid to use, call Bridgewater’s parts department [888-579-0048] with you VIN and they will supply the correct fluid. Pentosin CHF 11.S fluid is greenish in color while ATF is reddish. Old yucky ATF can be a reddish-brownish.

Further investigation suggests that when BMW switched to CHF 11.S steering fluid on most models beginning circa the E60 5- Series, they changed the fluid-reservoir cap such that it indicates that CHF 11.S is required. But what if you, like Jeff, need a reservoir for an older model? BMW thought of this as well, and provides a label indicating that ATF should be used.

The part number of this label for Jeff’s E39 is 71-24-6-798-132. Or you can make your own label like Jeff did. That’s what I would do. So too would Trip.

That’s all for now, bimmerphiles. See you next time.

Anyone wishing to contribute to Philes’ Forum can contact me at I’m interested in tech tips, repair / maintenance questions, repair horror stories, emissionsinspection sagas, product evaluations, etc.

© 2017; V.M. Lucariello, P.E.

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