Any obvious spots to check for a Urea leak?
 

We recently bought a 2010 ML350 Bluetec with about 130k miles on it. It had tons of regular maintenance as a corporate vehicle including replacing the oil cooler twice.

Unfortunately it also has a leak from the Urea tank.

Does anybody know common areas where they leak? Or if o rings are available?

So far all I'm finding are threads about failing heaters.

I just went through air spring repairs on two different cars that were the rescue of leaking o rings, not the actual air springs. And Id rather try replacing a few o rings rather than a $1000 tank. Yes I'm frugal, but more so I hate replacing perfectly good parts.

Here's what ours looked like after a recent 3 hour drive. Thankfully around town it's not so bad. https://cimg5.ibsrv.net/gimg/www.mbw...5e4e3757cc.jpg
8https://cimg4.ibsrv.net/gimg/www.mbw...78dd563aeb.jpg

Ouch. With such visible signs you should not have a problem to pinpoint the leak.
Just check it after shorter drive, not when everything is soaked.
Good technique is also wrap suspicious parts with paper towels.

Yeah hopefully it won't be too hard to spot. But given the cost of the system I'm just hoping I don't break anything!

I've decided to go for the DEF/EGR/DPF delete. At 20k miles, I've already had to replace the DEF tank heater, thankfully under warranty.
Warranty's over in October, doing the delete thing shortly thereafter.

https://cimg2.ibsrv.net/gimg/www.mbw...7a86a35e4c.jpg
The top of the tank was pretty bad. Thankfully it washes off and dissolves easily. I will keep an eye on it and check for leaks in a day or two.

Glad you got it figured out, and sad that a professional shop would forget something so simple!