USNA1970

So after owning my car for 6 months, it developed a slow oil leak. a few drops in the garage each night. Leak coming from RMS or IMS flange as it is coming from between engine and tranny. I made sure my oil was always at an acceptable level over the next few months. However, after about 2-3 months the leak had stopped. I have not had one drop on the garage floor in about 2 months. Has anyone had this happen? I've been using motul for the last two oil changes and redline the oil change before that. The leak started after using Redline. The two oil changes before redline was Mobil 1.

dkraige

Mine leaks if it sits for a long time, and stops leaking if it's driven daily. I've had a mechanic tell me this is pretty typical for the RMS; they leak if they sit. Don't know if he knows what he's talking about or just doesn't want to work on my car

USNA1970

I've been driving mine almost every day. I am wondering if doing three oil changes over the course of about 9k miles cleaned it so well that it started leaking past the RMS or the IMS flange. haha, probably not. But not sure why it hasn't leaked in a few months. I did use some of the lqui moly oil saver, but that was probably 3-4 months ago and I only used it once. I didn't use it in the last oil change. I guess I'll keep doing what I am doing and not change my oil type. Maybe Motul 5w40 is better for these leaks than 0W40 redline or Mobil 1.

Macster

The seal doesn't get dirty inside. As dkraige touched upon at least in some cases just frequent/regular use can keep the RMS from leaking.

My Boxster's RMS only leaked a few drops after I'd let the car sit for a long period of time, a week or so while I was away in my other car. But on a nearly 8K mile road trip the car never spotted one hotel parking lot with oil as I was driving it every day all day long. Even had the oil changed while I was on the road and using 0w-40 then too. When I got back home I booked the car in for a new RMS -- covered by the car's warranty.

At some point -- probably -- your car's RMS (or IMS end flange seal will leak more even if you continue to drive the car frequently and regularly. RMS leaks never get truely better on their own nor, I am told, do they get severe to the point keeping oil in the engine is a problem.

Just so you know, might as well mention that it is SOP to when replacing the RMS to replace the IMS end flange and its 3 bolts. Older cars with the factory IMS end flange can have the one with the crummy single o-ring vs. the 3 ribbed seal the new flange comes with. Additionally the new bolts are treated with something that when they are threaded into the block and torqued down create a thread seal.

The IMS end flange and its bolts are replaced because it is not possible to know if the leak is form just the RMS or from both the RMS and the end flange and its bolts.

USNA1970

Good info thanks! At some point I am going to get all that addressed but thinking of waiting until my clutch needs work. I bought the car with 47k and I now have 66k after 10 months. I like to drive to work every day and that is about 60 miles round trip. Oil analysis has been good and very little iron paste on the magnetic drain plug at oil changes. Just hoping I don't have one of those instant IMSB events.

Macster

Regular use and reasonably spaced oil/filter services can go a long way to having a long and relatively trouble free service life from your car.

For years now -- since maybe 2005 -- my work commute has been 60 miles (round trip) and the Boxster gets the call 3 or 4 days out of 5 days.

My 2002 Boxster is nearly to 309K miles now (last fill up on 2/24 the odometer was at 308892 miles) and still runs great and the engine and drivetrain show no signs of the nearly 1/3rd of a mllion miles of use.

'course, not all those miles were accumulated making the work commute. Sometimes -- several times a year in fact for most years (but not since 2012) -- the car gets the call for a nice long (4K/5K miles or more) road trip where I spend a week or so running around the western part of the USA.

USNA1970

That's good to hear. My previous car was a 98 M3. I bought it back in 2006 and it already had 174k. The PO drove long commutes. Anyway, I owned it for 8 years and when I sold it I just passed 335k miles. I pretty much did all my work. Never replaced clutch, did all the basic stuff but no major issues. I changed oil about 5-6k miles and just used mobil 1 or whatever synthetic was on sale.


Having said that, I was hoping to get at least half those miles out of my 02 996. I am wondering if the reason we see lower miles on these cars before major engine trouble is because people don't drive them as much as normal daily driver cars. Maybe my 996 can do about as well as my M3 its just that you don't read about it because most 911s don't get driven in winter and don't get driven 5 days a week etc.