My e320 is coming on 94K miles and I was wondering when do I need to get the timing chain replaced.

Many thanks,
CM

If it is a metal chain, then it should be changed at 90K to 100K.

But if it is a rubber belt.... 60K to 70K.

That is what my knowledge tells me, I am sure you already know this, but just in case you don't...

If a timing belt/chain were to break, the valves hit the cylinder heads causing servere damage.

Please make sure that you change it, but only by a competent mechanic or yourself if you trust that person in the mirror.

Your car has a strong double row chain with a short run from the cam to the crank.

On the M104 I would not say it is necessary to change the chain at 100k miles just for the fun of it. If the engine has been cared for and had regular oil changes, the chain should really last much much longer than 100k miles.

That being said, a check of the chain stretch will determine if the chain needs to be replaced. This is what you should use to determine if the chain needs a replacement if you are worried about it.

__________________
Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record

The double row chain on the M104 engine is very stout and with frequent oil changes can last a very long time. I have seen M104's and M111's (the four cylinder cousin to the M104) with 300,000km's (190K-miles) or more on the original chain without any noise from the chain.

A mechanic can check the chain for stretch by measuring the change in cam timing.

The only Mercedes engines I would change the chain as early as 100K-miles is some of the V-8 models with very long chains with severe direction changes. Also, some of the V-8's (especially the M116) have plastic guides that age badly.

__________________
John Shellenberg
1998 C230 "Black Betty" 240K

http://img31.exs.cx/img31/4050/tophat6.gif

I just had mine changed on the '94 wagon with 238,000 miles on it because it was 'a little slack'. I drive a lot and pretty much change my oil every month. I didn't know it is a double chain though . I know the wife's '99 E300 is double chain.

__________________
dtf
1994 E320 Wagon (Died @ 308,669 miles)
1995 E300 Diesel (228,000)
1999 E300 Turbodiesel ( died @ 255,000)
2006 Toyota Tundra SR5 AC 4X4 (115,000 miles) rusted frame - sold to chop shop
2011 Audi A4 Avant (165,000 miles) Seized engine - donated to Salvation Army
BMW 330 xi 6 speed manual (175,034 miles)
2014 E350 4Matic Wagon 128,000 miles
2018 Dodge Ram 21,000 miles

Drove my 1990 300E to 175K on original chain. I just had the chain replaced on my 1992 300E at 214K. I bought the '92 at 100K and have run it on Mobil 1 with changes at 3 to 5K, 95% long Interstate trips.

There was no noise, but thought it should be done. If you are changing the
oil and filter regularly, why worry about it?

Steve