How many of you actually drain the oil from the oil cooler in your M156?




isn’t there only one oil cooler? It’s part 209-500-01-00; and looks (at least) the length of the radiator. This is the one I’m replacing at least as it has the oil drain plug under the radiator towards the passenger front wheel. 



Sincerely,Marco Mercedes




Sincerely,Marco Mercedes
The S65 oil cooler should be located in the same exact spot as every other AMG of that era. If you lift the car up on a lift, and remove the front engine belly pan, you'll see the oil cooler, just in front of and below the radiator.
The oil cooler drain plugs is located on the below right side of the cooler. Sorry, but I can't seem to locate any of my photos. But I do have old threads that has it. The copper washer is embedded, so no new washer is needed.
I don't use a torque spec, when tightening, as I don't have a torque wrench that goes that low. But I believe the correct spec is 18-20 ft/lbs. I just tighten them both down snugly by feel, and never had a oil leak. But definitely order a new crush washer for the oil pan drain bolt. Remember that you don't want to use tremendous torque on either bolt, especially the oil cooler. I just tighten it until it's tight, then turn a 1/4 turn. And that is it.
William
take the o rings off and check where its at after a refill, or carefully slide in dipstick to where the o rings just touch the neck of tube and measure the difference. On mine the low mark is actually full. took me a while to work this one out!
take the o rings off and check where its at after a refill, or carefully slide in dipstick to where the o rings just touch the neck of tube and measure the difference. On mine the low mark is actually full. took me a while to work this one out!
The Best of Mercedes & AMG




This was after letting the oil warm up. Now thinking about it, I should recheck the oil level again.
It uses the same metal gasket as the oil pan. Remember not to over tighten it, or you risk cracking your oil cooler.

On a side note, the Black Series has a couple more oil coolers... Would you recommend also draining it once in a while?




On a side note, the Black Series has a couple more oil coolers... Would you recommend also draining it once in a while?
The secondary oil cooler that has a cooling fan attached could also be drained, by unbolted the lower drain tube, but would require replacing the o-ring.
I don't drain this because, disconnecting the drain lines along with replacing the o-ring, could result in leaks.
Sorry, don't have any photos, but did see some on the internet awhile back. I drain the oil cooler because they contain at least a 1/2 quart of oil.
And I prefer not to have that much oil mixing with the new oil, but it's inevitable. The BS does have additional coolers, I'm pretty sure that they must have drain plugs as well.
Last edited by Yuille36; Nov 12, 2019 at 09:49 AM.




Last edited by Yuille36; Nov 18, 2019 at 08:53 AM.




I do prefer to buy them directly from the dealer. That way, I can be assured that I have the right part. But if Autozone sells a 16mm aluminum or copper crush washer then it should fit.
Last edited by Yuille36; Jan 10, 2020 at 10:00 AM.






