Synthetic oil in 1988 560SEC? - Page 2 - PeachParts Mercedes-Benz Forum

lws1 · #16 05-29-2007, 10:13 PM

Quote:

Originally Posted by jhodg5ck

Valve guides etc usually run in the 4-5K range. The most you can expect from the originals is 200K @ which point they will be quite worn and sloppy. You can buy time by band-aiding the problem w/ new valve guide seals, but it is just that..a band-aid.

You'll know by the amount of oil your engine consumes over a given mileage, whether or not she smokes after sitting/idling..a compression test is also a good indication.

I've switched many cars over to synthetic, but they were all tight engines, ie no leaks, good heads etc.. If a car is burning oil/leaking it pays to stick w/ dino.

FYI, off the shelf consumer oils no longer have the necessary zinc/phosphate additives that our cars need to keep cams etc happy.

For Dino oil Valvoline's Racing 20/50 is good, or for synthetic I run Mobil 1 20/50 w/ GM valve/tappet additive (all the additives that manufacture are pulling out this puts back in). Or, any 4 stroke motorcycle oil is Good.

Jonathan

Thanks, Jonathan. I am going to try the Valvoline Racing 20/50 in my car. It has 161,000 miles and that's a good weight, right? I live in Miami and drive the car once a week.

t walgamuth · #17 05-30-2007, 06:05 AM

when i first got my 500sec i switched over to rotella in it. i found with the rotella one of my valves ticked for about ten minutes on startup until i had 1500 miles on the oil. so i switched to the mobil one 10 w 30 just to clean it out and next oil change switched back to the rotella. it ticked again so i switched to mobil one permanently.

i suppose it could have been an additive or characteristic that is beneficial to diesel engines causing the problem.

i think newer engine designs with much tighter tolerences are a lot more oil sensitive than the older designs i grew up with.

my conclusion for myself is to be very careful about using oil and oil weights specified by the manufacturer.

tom w