E55 Making a very Strange Noise From the Oil Pan Area
So my question is, what could cause the oil pump to make such a noise, and how to repair it? I have seen the infamous video where the guy from XF Motorsports makes the claim that the seal on his oil pump cost him an engine, and part of me does think this noise sounds vaguely reminiscent of a straw with a hole in it, only amplified many times. It could be that air bubbles are getting into the system and causing cavitation, which tends to make similar noises in power steering pumps for example.
The car has been making a sort of "groaning" noise off and on for a while now, and I think this may be the source of that sound. It often shuts up if you give the engine some revs, either through spirited driving or shifting to neutral for a moment and blipping the throttle.
I should think that having the steering rack off is actually a somewhat opportune time to do any sort of work on the oil pump, as from my understanding you need to drop the front subframe in order to get the oil pan off the car anyway.
Here is the video of the noise for reference.
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You will have to live with it as I know of no fix....
Last edited by SICAMG; Oct 21, 2020 at 08:46 PM.
I have had it for 6 years now and only a particular oil will make it quieter. I have completely dissasembled my engine and rebuilt it for race season...new bearings , OIL PUMP, and every other wear item and still it has the same noise.
Most complaints always start off the same way... "As soon as I started the car after my oil change there was this noise". Trust me I would love to know what it is as this winter it will be out again for some work so now is the chance.
I have had it for 6 years now and only a particular oil will make it quieter. I have completely dissasembled my engine and rebuilt it for race season...new bearings , OIL PUMP, and every other wear item and still it has the same noise.
Most complaints always start off the same way... "As soon as I started the car after my oil change there was this noise". Trust me I would love to know what it is as this winter it will be out again for some work so now is the chance.
Also, it has nothing to do with oil changes etc, and has been present for nearly a year now, and has been slowly gaining intensity.
Last edited by feeshta; Oct 23, 2020 at 02:17 AM.
When i pull in the pits from a 1/2 mile run.....not a sound. Let the car sit for an hour....there it is !!
If you keep reving the engine in neutral you can make it fade away to an extent.
When i pull in the pits from a 1/2 mile run.....not a sound. Let the car sit for an hour....there it is !!
If you keep reving the engine in neutral you can make it fade away to an extent.
I've seen mentions of switching to Liquimoly Brand and/or different oil weights to help quite this noise down. Which oil weight and/or oil additive as I can only assume that would be what gives with Liquimoly brand in particular, helps to calm down the noise? I've been using Mobil 1 0-40 full synthetic on it since I bought it. Getting much else requires a lot of planning ahead, as I have to order it from the USA. Oil prices here in Germany are absolutely Bonkers. Not joking, it's like 20 Euro per liter for regular non-synthetic.
THIS IS NOT NORMAL.
Clear enough?




THIS IS NOT NORMAL.
Clear enough?
Last edited by E55Greasemonkey; Oct 23, 2020 at 06:26 PM.




That said, I really don't see the point of taking the car in for an expensive evaluation procedure that can't actually correct any problems it may discover and cannot actually check the main potential trouble area I am worried about. It costs less to open the oil pan and replace the possibly faulty grommet, which the suggested procedure cannot evaluate the health of, as well as address any other issue that might be discovered.
I'm already planning on doing the job, just need to sort out some other potential concurrent work such as replacing the steering rack which is worn out. Having some trouble finding a shop that will confirm that the part they want to send me in exchange is actually a steering rack from a later model year E55 like my 06, rather than the slower rack from the earlier model years. Can buy one of the newer ones of course, but they want crazy money even for refurbished ones. Generally over $1200, even after core exchange. Can't imagine it would cost $3-400 worth of labor and parts to refresh this steering rack.
So, if you execute opening the pan, please keep us posted what is it like there and if noises change or settle when you change the O-ring. I can't remember if XF Motorsport ever reported anything regarding the noise in his.
Even though there is cavitation, regardless of the the reason, it might not affect the oil pressure directly. If front pump cavitates, the secondary still might feed the engine well enough. If the secondary cavitates, it's not good, but lubrication might still be sufficient for the engine and thus we don't see damages.
Btw, my car has 90K kilometers. But these start to be oldish, so it's no suprise if some rubber gets hard and brittle even though being specified for chemicals. I'm running Liqui Moly 0w40 + Mos2. Pretty sama noise level as Mobil 0w40. LM 5w40 was louder or maybe not louder but it didn't fade away very easily even with revs.
So, if you execute opening the pan, please keep us posted what is it like there and if noises change or settle when you change the O-ring. I can't remember if XF Motorsport ever reported anything regarding the noise in his.
Even though there is cavitation, regardless of the the reason, it might not affect the oil pressure directly. If front pump cavitates, the secondary still might feed the engine well enough. If the secondary cavitates, it's not good, but lubrication might still be sufficient for the engine and thus we don't see damages.
Btw, my car has 90K kilometers. But these start to be oldish, so it's no suprise if some rubber gets hard and brittle even though being specified for chemicals. I'm running Liqui Moly 0w40 + Mos2. Pretty sama noise level as Mobil 0w40. LM 5w40 was louder or maybe not louder but it didn't fade away very easily even with revs.
I am planning to do the job is a couple weeks. Can't drive the car right now due to an airmatic leak, and decided to go with BC Racing coiloversas a replacement option, which should be here in about a week. Then I have 2 weeks of leave in late November, and plan to just do the whole list(oil pan, suspension, and steering rack) at once. Might take a few days to finish that whole list, but its not like I have anything better to do with my time off given that travel is a no-go now.
I'll try to see what the seal status of the grommet is if possible and report back, as well as the the status of the noise after completion.



