Hello has anyone experienced a diesel fuel leak from above the fuel tank. It seems that it is just a small enough leak to cause diesel fuel to run down the sides of the tank. I took it to a shop and they said that it could be the fuel pump or fuel return line leaking but would have to drop the tank to inspect to make sure of what it is. They also said to drop the tank you have to pull the drive shaft and also remove some of the exhaust pipes. I was wondering if you can access the fuel pump thru a hatch under the seats like you can on 2008 GL450's. The shop that looked at it wanted over $4k so I said heck no. If anyone has some suggestions let me know. I do most my own mechanic work but I cant seem to find any Youtube videos or anything online about fuel leaking from the tank. This leak is way back from the engine and is coming from above the tank. Not sure if it is leaking from the lock ring and seal that holds the fuel pump in or not. It seems to leak slightly more when it has a full tank of fuel compared to half or less.

@Keyser4 Please post your VIN and someone can take a look in WIS for you.

Do you think you could get a look on top of the tank with a borescope type camera? $4k is a lot to spent when it's probably a $0.50 o-ring.