S-Class (W221) 2007-2013: S 320 CDI, S 350, S 450, S 500, S 550, S 420 CDI, S 600

Line into radiator - oil cooler?

Old Sep 15, 2023 | 11:21 AM
  #1  
E.Murray's Avatar
Thread Starter
Newbie
 
Joined: Jun 2023
Posts: 13
Likes: 4
2008 S63
Line into radiator - oil cooler?

I have a small oil leak somewhere under the hood. I noticed last time I drove the car that I could smell oil. When I popped the hood, there is evidence of oil that has been blown (by the fan or just driving) on the passenger's side of the engine bay. I noticed that the line in the picture feels loose. Two questions. First, is this a transmission or oil cooler line? Second, how is it connected? I can wiggle it around, which I figure isn't normal. But I don't see how the connector works. Can something just be tightened or is something broken?
Thanks!

Reply
Old Sep 15, 2023 | 12:03 PM
  #2  
BOTUS's Avatar
MBWorld Fanatic!
10 Year Member
Community Builder
Community Influencer
Liked
 
Joined: Aug 2014
Posts: 5,322
Likes: 1,678
S500
trans cooler isn't it....

not a great idea to lose fluid from there... would be worth changing the fluid and getting it full - needs doing every 37k miles on the 7g boxes - they changed their minds after they all died in the warranty period - from never to a one off 37k mile change - then changed again to every 37k miles as they are so well made they still died
Reply
Old Sep 15, 2023 | 02:02 PM
  #3  
E.Murray's Avatar
Thread Starter
Newbie
 
Joined: Jun 2023
Posts: 13
Likes: 4
2008 S63
Thanks. How do I tighten it up?
Reply
Old Sep 18, 2023 | 01:48 PM
  #4  
Shadly1's Avatar
Senior Member
5 Year Member
Liked
Loved
 
Joined: May 2019
Posts: 305
Likes: 114
2007 S550
Originally Posted by E.Murray
Thanks. How do I tighten it up?
Pull the clip, pull out the tube, replace the o-ring, install the clip, push in the tube until it clicks. You wont lose much trans fluid at all doing this but you have already lost some. The o-ring replacement will only stop additional fluid loss. You really need to do a full fluid replacement so you can get the right amount in there.
Reply
Old Sep 20, 2023 | 08:28 AM
  #5  
sdhayuj's Avatar
Junior Member
 
Joined: Sep 2023
Posts: 33
Likes: 2
kia picanto
This is 100% doable without taking literally anything off. Maybe the air box for a little extra room but it’s all accessible once you take upper radiator hose off.



Kodi

Last edited by sdhayuj; Sep 20, 2023 at 07:25 PM.
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 09:40 AM.

story-0
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

Slideshow: Mercedes-AMG's new electric GT 4-Door Coupe trades combustion for software, synthetic noise, and more than 1,100 horsepower.

By Verdad Gallardo | 2026-05-20 20:08:15


VIEW MORE
story-1
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-2
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-3
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-4
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-5
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-6
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-7
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-8
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-9
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE