MB recommended oil and oil change interval? 4.5LV8

[edboyles]

for a 1980-450SL with the 4.5L engine? What does MB recommend as oit type and how long before oil changes? Thanks.......

[rickjordan]

I gather your owner's manual is missing. I'll quote the owners manual for my 380SL. FOr oil/filter change "to be carried out every 7500 miles, but at least once a year." "Under severe operating conditions the oil and filter should be changed every 3750 miles"

As for type. Let's start off with the weights the owner's manual recommends. For temps. of -4 and up use 10W-40. For temps of +5 and above use 15W-40 or 15W-50. For temps from +32 and above use 20W-50. I don't about the 4.5 V8 but my 3.8 takes 8.5 qts of oil.

Now for the explosive subject of what type of oil to use. The owner's manual does not state oil type as in conventional vs synthetic. It just lists weights. For the above recommended weights, you won't find a synthetic 10W-40 15W-40 or 20W-50. You can get 15W-50 from Mobil 1.

As to which one is best, I will avoid starting another oil debate. That is why I am quoting the owner's manual and not interjecting my opinion on which way to go.

Any brand oil from today will exceed the oil standards that were in place in 1980.

[edboyles]

Thanks Rick for the reply. My Euro version has the German manual so I first used 20W-50 by looking at previous oil change records and changed it at 3000 miles. This next round I used the same brand but a 10W-40. My oil still looked clean with 3000 miles and I heard that due to the large sump size of 8.5 qts that the oil change interval could be extended. Thanks for clearing this up. One day I will be able to pick up a English version owners manual. Here in southern Arkansas it gets hot!! Thanks again......Eric

[rickjordan]

Well, the extended interval would only apply to gas engines. My wife's 87TD also has a 8.5 qt sump, but requires oil changes every 5,000 miles. This is simply because it's a diesel.

[kip Foss]

Eric,

You don't have enough time between now and when you die to read all the messages on this site about oil.

At 62 and having driven many, many gas and Diesel cars and trucks over 150k miles each in the US and 20 years overseas and having NEVER lost an engine from an oil related problem or, for that matter, even had the slightest oil related problem, I suggest a couple of things.

To start with you must rememberr that when talking to MB owners you are dealing with a bunch of anal retentives about their car maintenance. I am not saying that these guys are not top notch but they get a bit bound up about oil.

About 6 years ago I read an article in the Consummer Union magazine about a test they did involving 77 New York taxies. They put new rebuilt 350 engines in these cars and tested them with a wide variety of oil brands, types, change intervals, additives, and all things related to oil. I don't remember just how long they ran the taxis but I think that it was long enough so that they could say that they had given the test a fair go.

The results were basically this: Straight name brand non-synthetic 30 wt. oil without any store bought additives and changed at 6 to 7K miles is as good as you can get. They concluded that synthetic oil and store bought additives were a waste of money.

I run a parts shop brand 30 wt. oil in all my 5 cars. The oil has an API seal just as the major name brands have and conforms to all the same specs. I change my oil and filter at 10k miles. I have torn into 3 engines in the 17 years that I have been back in the States and each was as clean as a whistle inside. I now drive a 1982 GGM 6.2 Diesel with 240k miles on it and it still runs at 50-60psi oil pressure. I live in S.Tx. where it is hot and I drive fast (I have the insurance record to prove it), esp. in my 1977 450slc and as I said have never had an oil problem.

A lot of people on these sites swear by synthetic yet most have never lot an engine to dino oil. Some may have but it was probably an bad oil pump or some such that carsed the failure rather that a failure of the oil. I think syn. oil is expensive and overrated. Perhaps if you are doing 70K a year in the desert it might be worth the effort, but most MB owners, esp. those with older cars are lucky to put 10k a year on their car.

Save your money. Use a name brand dino oil, change your oil and fuel filter and rotate your tires every 10k miles. Ten K is easy to keep track of and you can put the money you save into maintenance.