Not another oil confusion
 

Guys, I just need some advice on which oil weight to use.
I have a 1994 C280 with 91,000 miles.
Should I use 10W 30, 10w 40, or what?
I know I won't be using a synthetic oil & I will change it every 3000 mile while it's hot:D

Thank you!

It's my understanding that Mercedes now has two specifications for oil (gasoline engines). For engines manufactured from 1997 they recommend 0W-40 Mobil 1. There is a different specification for all others. Check the oil container to see if the oil meets the MB specification.

I do know that 0W-30, 5W-30 and 10W-30 DO NOT meet MB specifications (even if it's a synthetic).

I'd recommend 10W-40, 15W-50 or 20W-50 depending on where you live. Low viscosity oil has been pushed by auto companies to help them with their CAFE averages under the guise that it's good for the consumer. As someone once said, you have to wonder if any of those auto engineers in Detroit actually use that crap they recommend.

I change my own oil and use Mobil 1 15W-50. The cost of this oil and MB filter is no more expensive than if I took my car to some fast oil change place that uses no name oil and American filters.

BTW, look under the hood of a new Mercedes and notice the sticker that says you should use Mobil 1.

If your car is one of those FSS cars, then you should be using full synthetic. Regardless of which oil you use, it should be nothing less than xxW-40.

The previous owner has been using 10W 30, I guess I will have to switch. I live in Portland, OR with temp. range from about 30-100 degree, so which one is my best bet? 10W 40 or 15W 50 consider that I have 91,000 miles on the engine?

It's unfortunate that the previous owner used that oil. I don't have the owner's manual for your car but I'll bet it doesn't recommend 10W-30.

A person can argue that using a good brand of petroleum based oil changed frequently is more than adequate. I agree. However, I personally avoid the lighter weight oils and using a synthetic allows me to use a 15W-50 oil in temps where a lighter weight petro based oil would be needed.

My suggestion is to use a good name brand petroleum based 10W-40.

10W 40.

Thanks guys!
I will be using 10W 40 since the owner's manual does not say which oil to use.