300E - W124 durability
 

I see many sigs on this board indicating high mileage for this model engine. What is a reasonable expectation before major work is required. My '86 (owned since new) has 170K and has not yet required major work, not even valve stem seals. It uses a quart about every 1,500 miles. Can I reasonably expect over 200K? I'm not asking for guarantees, just educated guesses. :)

Well from my experience with my previous and current 300E I would look into:

Rear control arms

valve job or stem seals (they will go bad soon)

transmission


Anyone else have ideas??

I just finished a valve job on my car.
 

My car has 250K+. It was consuming 1 quart of oil for every gas tank. In my case, I think it was a combination of a leak in the front upper timing chain cover and bad valve guides and seals. If you don't mind small leaks and keep an eye on the oil consumption, your car should last for another 100K miles without touching it. You can also try replacing the seals to minimize oil consumption, which can be done without taking the engine apart, and it is relatively cheap. Keep up with oil changes.
Good luck!

Since66

Our 91 300E (2315k miles) uses oil, but it is from the front cover seal. I slowed that seeping by trying the "high mileage oil" MaxLife from Valvoline. It improved the oil consumption (leak).

It is my understanding that in 1990 or 1991 the valve guides and valve stem seals were improved. I also believe that in the last ten years oils have very much improved so it doesn't surprise me that your '87 with 170k miles is doing well.

I just started using Mobil 1 15w-50 in the project '87 190e. The car seems to really like this oil. It starts easily and even in our 100+ degree days, never gets too hot. We also noticed the engine to be much smoother. This I can't explain but it is so.

I have been following the Mercedes service recommendations carefully. I also have flushed the power steering fluid and change its filter. All the cars have synthetic AFT and differential lubes.

Enjoy your drive,

Haasman

Thanks for the input. The A/C was totally redone last year (compressor + freon conversion) and one of the rear suspension links a while back. Just did front .... and rear shocks. I've previously noticed the jackpoint rust, and there is a "thunk" coming on or off the accelerator in normal driving. Might be a flex-disc or.......!
I'm keeping it for the "duration" though.

All your comments are appreciated.

My 300TE has the normal front cover leak (will have to fix that sometime) and has had the head rebuilt (PO -- about 160000 miles). Other than some fuel delivery trouble, nothing else.

With good oil and proper change intervals, I'd expect the bottom of the engine to last at least 500,000 miles without work. Probably going to have to do head work once or twice, nothing lasts forever.

Older ones had valve guide wear problems, the replacement guides are harder, shouldn't recur.

Bodywise, watch out for rust at the jack points (need to fix this on the 300 TE, passenger front), the rear suspension links will fail, the replacements are from the 210 chassis and will last longer, normal AC problems. Fuel distrubutor will eventually go, cost big $ these days for some reason.

Else pretty maintenance free.

Peter

Front flex disk is a 60,000 mile part most of the time, causes the thump.

Another source of thumps is the differential mounts on the rear subframe. The rubber deteriorates, and the steel sleeve bangs on the subframe. You can check by taking a peek at them from the rear of the car -- if they are not both centered, or if they more when you apply upward force with a floor jack, they are toast.

If you are also getting some torque steer, pull the rear wheels and take a look at the torque link -- its the diagonal one from the wheel carrier to the inside of the subframe. Shreds of rubber indicate a bad bushing, meaning a new link.

The rear subframe mounts will eventually go bad, too, will also cause a thump.

I know all this because I just put some links in the 300D, and will be doing the rest (might as well put them all in, why do it one at a time?) and subframe mounts, mine are cracked.

Peter

To answer your original question concerning the engine, mine is at 256K and going strong. It's the rest of the car that will keep you buisy, not the engine. The M103 engine is an amazingly great engineering masterpiece.

Good luck,

I had a 86 300e 5 spd , i bought it with 350k and drove it to 400k with NO engine problems, used a qt. of oil every 1500 miles or so. still got it up to 130mph on the highwway too.

Mines has 252k, driving it coast to coast next week. Mileage really means nothing on these things. Maintenance is key. :)

205k- running strong and smooth. Engine has never been touched. 1 quart every 1500 miles, though I am losing some of this around a leaky front cover.