please I need your help :)

You have now passed the Quiz.

 

#1 - Not sure. Guessing it could be an ABS modulator?

#2 - Looks like the trolley/brakesaver valve.

#3 - Auto slack adjuster

#4 - Piggyback brake chamber (MGM style)

#5 - Some kind of shroud or guard for a Mercedes engine or truck

 

#5 according to what I found on a cursory search:

Product Details | OIL PAN
2520-01-301-9948 A metal item designed to be attached to the lower portion of an internal combustion engine, compressor, hydraulic transmission, and the like. It serves as a reservoir for lubrication oil and may include baffle(s), oil cooler connectors, or the like. For items furnished with gasket(s), hardware, drain plugs, and the like, see PARTS KIT, OIL PAN.20425200039Vehicular Power Transmission Components28050063Gasoline Reciprocating Engines, Except Aircraft; and Components28150029Diesel Engines and Components43100028Compressors and Vacuum Pumps

Part Alternates: A4602700412, 101007008010A, 4538742867, 4538742-867, 460 270 04 12, 4602700412, 94445991, 94445-991, 2520-01-301-9948, 01-301-9948, 2520013019948, 013019948

Vehicular Equipment Components | Vehicular Power Transmission Components

 

The bottom black one is an oil pan made by Daimler/Chrysler. It's at least 11 years old.

 

Hello,
So you now have a complete list of part numbers for these items.
It is now just an easy search on Google to identify them.
If they are for sale as new old stock, I would list at 60 percent of listed value.

 

Wtf

 

The top part has a stamped serial number on the plate below the brand.

The second part concerns me. That might actually be a railroad locomotive device. From a Alco engine. But don't look at me. What do I know.

The rest of them are truck parts related to the air braking system with the exception of the last one that says Freight-liner Oil Pan or a Mercedes car or truck. Its all there on that label.

I don't generally do quizzes but if you are sitting on heavy truck parts with nothing going on with them in your life I wonder what in the world are you doing with them? Then I get suspicious etc if I think too much.