What is the real service interval for a fuel filter?
 

I'm trying to decide what the proper service interval is for a fuel filter on a MY99 E300. I'm not exactly remembering at the moment what the interval is in the manual, I'm thinking maybe it's 30K, or 45K. Whatever.... I haven't changed mine yet, and I'd like to determine when I really should.

Thanks......

All it takes is one bad load of fuel to clog a clean filter. A lot of folks just let the filter tell them when it's time for a new one. The loss of power is pretty noticable when the filter gets obstructed.

30k is scheduled, but I seem to do mine every 20-25k. I can usually tell when my mpg starts going down.

It's every 60,000 miles for both filters on the E300TD.

Len

a very senior member here would say until it won't pass fuel anymore..
for me i changed a filter that appeared to be good in the end (the canister type) and have been running it's replacement for at least 4 years.. with no issues.
of course a w123 has the clear prefilter to be able to judge things fairly easily.

when in doubt change it as they are cheap insurance and keep a spare in the trunk!

The clear pre filter is the way to go. Since I changed to a clear pre filter I haven't changed it for 50,000 + miles. I do change the main filter about every 25,000 mi because my 603 has remined me to do so twice - just a slight lessening of power. But, as previously said, one load of bad fuel and you may need more than one filter change! Try to buy your fuel at a station that sells a lot of diesel fuel; where the local truckers use.:) :)