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2002 SLK32 Silver Renntech pullies
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Discussion Starter #1 (Edited)
Sorry if this is redundant for yet another oil change note.
I was changing oil yesterday. Since I didn't have a pump, I did the traditional drain and fill. The following may help someone who wants to do the drain and refill.

1) Jack up the car, leave on jack stands.

2) Before you can get to the drain plug, you need to remove the plastic under body cover. Use an 8mm socket to take out 4 screws that holds the under body cover. I found out that my interchangeable screw driver base (without a tip) was actually 8mm. So I used that.
There is the 5th screw, a 10 mm, on the left side towards the front that also need to be taken out. Once these 5 screws are out, you can take down the whole plastic cover.

3) With the cover removed, you can identify the drain plug, a small (13mm) bolt on the left side on the aluminum oil pan. Take that out and oil starts flowing. In my case, since the oil was pretty hot, I used a double gloved hand to quickly remove the plug/washer out of the running hot oil.

4) While the oil is draining, you need to take out the oil filter on the top (once you break the seal, more old oil will come out at the bottom). Remember to place all 4 o-rings (3 for the shaft, 1 for the cap) that should come with the new filter.

5) Install new filter.

6) Plug back the 13mm drain plug with a new copper washer.

7) Add oil BEFORE putting back the body cover. Check oil level.

8) Start engine, check for any leak at the drain plug, and at filter seal. If no leak,

9) Stop engine. While waiting for the oil to return to the pan, put back the cover. Lower the car, reset the computer.

10) Now check oil level again. I had to add almost another qt. You're done.

Folks, If I miss anything, please add.

What I found was that the under body cover keeps much heat from dissipating. It doesn't seem to provide much protection. I think if next time I should just remove it. Will probably see the engine temp go down multiple degrees.

Jerry
 

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2003 SLK32 AMG
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What I found was that the under body cover keeps much heat from dissipating. It doesn't seem to provide much protection. I think if next time I should just remove it. Will probably see the engine temp go down multiple degrees.
Imagine though it must also help keep the water mud and other road stuff out the engine bay. May help aerodynamics too at speed, especially on the 32.
 

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2002 SLK32 Silver Renntech pullies
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Discussion Starter #3 (Edited)
Possibly. I shall test it without the cover at speed.
I hardly drive mine in the mud or snow, or even in rain.
 

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SLK32, ML430
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My last oil change using a topsider I was curious to see how good of a job the top sider did in removing all the old oil.

So after removing a vast majority of the old oil I dumped in 1/2 a quart of new mobile 1. After letting it sit for a couple of minutes I worked the topsider again. After just a bit of used oil the clean fresh oil started to come out and I would guess I got very close to 1/2 a quart of fresh oil out.

As others have said the topsider does just as good of a job in our car as the drain plug.
 

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2002 SLK32 Silver Renntech pullies
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Discussion Starter #6 (Edited)
How much oil did ya use and did ya use for oil?
Used 0w40 M1. I got out 7.8 Qts in 10 min. It was still coming out but very slowly. I didn't bather waiting. I figure had I really waited for an hour or two, I would have collected another 1/3 qt maybe? I jacked up the right (driver) side a little higher than the left.

BTW, the old oil had been in the car for almost 2 years, looked really black. I felt bad for not changing it sooner. Was trusting the computer to tell me when. The computer initially was calculating the miles left, but two weeks ago suddenly changed to days left. I guess the max time it would allow for the oil to sit in the car is about 2 years. I had only driven this particular car like 5000 mile during this time, never reached the 10,000 mark.
 

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2002 SLK 32 AMG, bone stock. 1987 190E 2.3-16 valve (destroyed). 2005 E320 new toy.
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Imagine though it must also help keep the water mud and other road stuff out the engine bay. May help aerodynamics too at speed, especially on the 32.
Actually I believe it maintains the airflow past the entire engine and exhaust system, and that will help keep everything cooler in the long run.
 

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Discussion Starter #9 (Edited)
Actually I believe it maintains the airflow past the entire engine and exhaust system, and that will help keep everything cooler in the long run.
The cat-exhaust actually need to stay hot for it to do its thing and exhaust maintain flow velocity.
 

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2002 SLK 32 AMG, bone stock. 1987 190E 2.3-16 valve (destroyed). 2005 E320 new toy.
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The cat-exhaust actually need to stay hot for it to do its thing and exhaust maintain flow velocity.
The front cats are well behind the end of the lower panel, and at least partially in the open, so I don't see where that has a bearing on what I said.... :)
 

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2001 SLK 320(217K Miles), 2002 E320 Special Edition(183K Miles)
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The front cats are well behind the end of the lower panel, and at least partially in the open, so I don't see where that has a bearing on what I said.... :)
Actually, you're not that far off. The underbody covering started after the 1st fuel shortage in the mid-70's. The idea was two-fold: (1) Improve the underbody airflow to increase aerodynamics and thus reduce fuel consumption. Of course, at the same time Formula 1 racing showed that it also increased the top-speed by having improved underbody airflow. (2) Help the engine to reach optimal operating temperature quicker and thus reduce the time that the choke was required. When catalytic converters became the norm, this also helped to heat up the catalytic converters faster, since the engine reached optimal temperature faster and also reduced heat-loss on the exhaust manifold.. Now if you have a SLK320, you also have double-walled manifolds to reduce temperature losses even further - so that's why one of the reasons why the 320 engine is rated SULEV.

So while the engine compartment temperature are higher than it would be with the underbody tray, everything has been designed with that in mind. So unless you were stupid enough to just remove your stock cold-air intake to replace with this (old-fashioned) oil-saturated sponge filter (which will remain nameless :D) WITHOUT fashioning a new cold-air intake box, you will not see any benefit by removing the underbody panel.

You will however loose top speed and increase fuel consumption by removing it.
 
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