Oil Pans/drain plugs Fragile????
 

Hi,

Are these oil pans (W166) known to be temperamental in terms of leaking drain plugs?

Moved to new town.

Found a new Indy garage and had oil changed a couple times ('18 GLE 350).

Most recently discover oil spots on driveway.

Brought it back and left it.

Mechanic called and said "Oil drain plug is causing leak, very fine treads, will have to put in a new oil pan".

I said that his shop changed the oil last.

He said some stuff about how the plug and pan break down over time from use and thats why the dealerships suck the oil out of the dip stick tube.

I feel like he is lying to me.

Is this your experience? Has not been my experience for several years of driving these cars.

Thanks,
Peter
2018 GLE350 4matic 60k
2017 GLE350 4matic 100k (sold)

They're as fragile as any other steel oil pan and oil drain. There is a copper washer on the drain plug that's supposed to be replaced at each oil change (if you drain it from the pan) that seals the connection so it doesn't leak. If that washer hasn't been replaced, it could leak. It's also possible, of course, that the shop cross-threaded the drain plug in the hole, and it's leaking. If that's the case, you'll have to fight with them to get it fixed.

Once you get this issue resolved, it's time for you to find a new shop.

Sadly, I think they cross threaded it and made up a story.
I will look for another shop.

I've been changing my own oil on the dozens of cars I've owned over several decades, and I have never stripped or cross threaded an oil drain plug. But then I haven't used an air hammer wih a broken torque limiter to save myself 30 seconds.

He stripped the threads on your oil pan and is too scared to admit it. These are robust oil pans if the screw is not overtightened and a new crush washer is used every time.

If it is leaking oil from the drain plug I would install a new drain plug and new washer and see if it fixes it. Even stop at the Mercedes dealer for the drain plug and washer, they arent expensive. I think the drain plug torque spec is 22ft/lbs. I havent personally seen a GLE drain plug but the drain plug in my C300 is not fine thread, so the "fine thread" comment seems suspect to me.

If the threads are stripped then someone put the drain plug on way too tight.

I work on my own cars since im cheap, enjoy working on it actually, and dont really trust shops.

Next oil change i would install the new drain plug and gasket, torque the drain plug to proper spec, then pour in a quart of oil and wait to see if it leaks. if all good fill the rest of the oil.

If you plan to take it to a shop to do the oil maybe its worth buying at least the washers on your own and giving them to the shop. They are cheap if ordered online, like 19 cents each. I dont see a reason to replace the drain plug since it should last the life of the car.

Quick story why I dont trust shops. Years ago I cross threaded a sway bar bolt so drove to a local shop thinking they can simply rethread the hole for me. Kid put the car on the lift then started repeating "oh man, oh man, that's not good" over and over. I asked whats the problem where he said i need an entire new wheel carrier. I told him hes crazy and to get it off the lift, how i was expecting a simple rethread job for $20. He said he can try that, where he did and fixed the issue. Charged me $40. Since then I bought my own tap and die set to do it myself if needed.

Then more recently i needed a new TPMS installed in a wheel. Bought the new sensor and took it to a local tire shop. Things went great, only charged me $20 to swap the sensor. BUT a week later i went to install new sway bar links and could not get 3 of the wheel bolts. He put them back so tight i ended up using a 4' length of pipe over my breaker bar to get the bolts off. Im not exactly a weak guy so if i couldnt budge them with my breaker bar theres something really wrong, nevermind needing a 4' piece of pipe.


I think these are the right parts, may want to double check.

https://cimg6.ibsrv.net/gimg/www.mbw...4d0c5f73fe.png

https://cimg6.ibsrv.net/gimg/www.mbw...93bb82c2ae.png


https://cimg2.ibsrv.net/gimg/www.mbw...f28f92e545.png

https://cimg8.ibsrv.net/gimg/www.mbw...37a4727253.png

And there are progressively more complicated remedies.

https://knowhow.napaonline.com/cross...lug-solutions/

You need to make them fix it at their cost, preferably by a Mercedes dealer, so you have more confidence that it was done correctly and with Mercedes parts.