98 ML320 work done, work in progress, and a couple of questions! - PeachParts Mercedes-Benz Forum

1994C220 · #1 03-23-2005, 11:33 PM

Hey guys...I have been reading posts nonstop it seems for the past few days and have a couple of questions.

The bad news is that I am replacing the Transfer Case but was able to find a decent one for $650 used, out of a 99 ML430. Is there anything I should watch while installing the transfer case? I have been assured its the updated 52/48 split, but is there a way to tell? Serial # or a specific thing that it would have that the 50/50 one wouldnt? Also, how good of a fix it is to fix the transfer case? In other words, does it go out every couple of years? Or can I rest assured that I wont have to mess with it again?

Now to the fuel filter. According to the diagrams from other posts, I have the newer fuel filter because I have the fuel loop that goes back towards the fuel tank instead of the end that just goes on to engine. This is the first good news Ive had this year! Unfortunately, I do not know when the last time it was replaced! The car was bought with around 84K miles and it is now at 126K. The fuel still goes all the way to full when I fill up, so I think the pump is ok. My question on this is, should I replace the fuel filter anyway? Also, what about the fuel pump? Should I replace it? My wife said that the ML wanted to die on her one time a few months back, but it has never done it since....Also, on this point, I wanted to see why it is necessary to take the seat out to get to the pump? I went in and after folding and sliding seat forward, had very good access to the cover plate(i actually pried it off(need to reseal) and it looks like the pump just screws right out...doesnt it? I wasnt able to find anything on the board regarding the actual procedure to swap it out for new one....Cant a new one be installed without the hassle of removing seat? I know it looks pretty long, but it really looks like there is enough room to clear.

Thanks for your help...Also, since Im spending all this money to get this ML back to perfect, anything else that I should replace just for safety's sake or peace of mind? I already have new radiator, water pump, window switches, oil filler cap($5), tie rod ends, transfer case(soon), ac compressor, and MAF. The sunroof has a broken bracket, but I never use sunroof so i havent bothered to look into fixing it.

Carlisle · #2 03-28-2005, 02:11 PM

I also have a 98 ML320. I bought it new.

Regarding the fuel filter: The update was not available until April 2001, so it is very likely the update was done just prior to sale. MB does not call for replacing the filter until 100K. You should not have anything to worry about for a while yet.

Regarding the Fuel Pump: Just because the gauge reads full does not mean the pump is alright. It means the level was adjusted which could have been done when the filter was updated. The functioning of the pump and the gauge are separate issues. They are a single unit, but operate independently. My gauge was fine, but my pump failed. BTW, this update means the dealer opened up the fuel tank access port making it easier for you now. I have 130K and did the filter very recently. When I took off the electrical connection at the fuel pump, I noticed green corrosion on the 12+ contact (green wire). Ultimately the pump went on my wife but only a few miles away. I replaced the pump and the wiring harness. I suggest you open up the access port and determine if the pump is original. A new one is $180 to $200 and easy to replace. If you have corrosion, let me know and I will advise the best solution.

Regarding the back seat: Move the driver's seat and the rear seat forward. You only need to remove the four bolts holding the two bracket furthest to the rear. The seat will then swing forward and you can brace it up while you work on the fuel pump.

Any more questions?

Gilly · #3 03-28-2005, 09:35 PM

The fuel filter replacement is done every 60,000 miles.
Gilly