I use the electric fan/shroud setup from a '03 Viper on my cuda. Pretty cheap if you have a friend at a dealership get it for you w/ their discount. It has 2 speeds...I just use the lower speed setting. Cools my hemi good.
I do have a big Griffin radiator that does a real good job too.

True about a poorly designed fan drawing excessive amperage.

The OEM fans all draw fairly high current because of their capacity. There's no free lunch. Hard work requires hard effort.

The Mercedes fan shown above is by far the most powerful I've dealt with and is a really nice fit on our factory radiators. It spikes over 60 amps on soft startup and pulls more than 50 amps at full speed. Lower speeds obviously pull less amperage.

Spal makes good stuff. I've used their fans. Flexalite is hit and miss. Their low priced fans are too weak for primary cooling.

What's the part #, application & pricing on that Mercedes fan?

The radiator is a significant obstruction to air flow. A properly set up car will control the air well enough to shove it through the radiator at speed. It will reach a limit and begin to spill out around the front of the car.

The reason you see chin spoilers under and behind front bumpers is to create a low pressure area in the engine compartment. That helps draw the air through the radiator.

A pusher fan has to be crazy strong. It is hanging out in front of the radiator where air flow is highest. If the fan isn't capable of moving air as fast as the natural flow it will become an obstruction.

I have tested this myself. A pair of typical parts house fans, when installed in a pusher location, caused higher engine temperatures when powered up. The engine cooled back down when the fans were turned off. Various speeds were tried. At 45 mph and above the engine heat increased.

Putting the fan behind the radiator gives it a lower velocity and lower volume air flow to deal with. Powerful fans perform well in this position.

Shrouds are just as critical with electrics as they are with mechanical fans. In one pair of tightly shrouded puller electrics I experienced heating problems at speed. I cut openings in the shroud and made flaps that were slightly larger than the openings. The fans would draw them closed at low speeds and the natural air flow would blow them open at speed.

Mercedes C230 through C320 from 2001 to 2006.

Aftermarket fans will require Hooziewhatsits controller (in the Moparts Products section). A direct 12 V line will burn them out quickly. Some factory fans can take a direct power input without a controller but that makes them run at insane speeds full time.
Factory fans are quite expensive.

We went through great lengths to test factory Mercedes vehicles and find out what kind of signal they used to power the fans.

100%

The OP's comment about I need a shallow depth of less than 3 inches
Led me to post what I did. I am Ass-uming the Mercedes fan, nor any of the other OEM suggestions will meet his space requirements. Maybe I am wrong and mis-informed but to my knowledge, Efficient OEM fans require both amperage and space. The space is usually the issue in my experience.
When Space is lacking creativity, IE: custom build is required. Again, correct me if I'm wrong.

Expensive,... IF, looking for new & OEM.

Had a friend in the local Dodge dealership try'n get me one for cost from the closest Mercedes dealer & the Mercedes parts guy wouldn't cut any slack on it. Don't remember for sure but think it was in the $550-650 range,...been a bit to long ago!

Had to dig back 3 yrs for the receipt on the new one I found on the net at Autotech in Nashville, Tn. $489.97 ymmv. Think I paid high 300's for the twin 12" spal's 15 yrs ago.

P/N A203 500 16 93 was the type shroud i liked.



PS: My fan motor ended up being 3&5/16" from the core.

I got lucky and found mine at a junkyard for $100. Check out car-parts.com

I would,ve done that also, if I was working on one of my other "gear head" projects,...but this one,s a bit different, with most everything new on it.

I do need to measure from core to shortened pump shaft for this thread.

I went out and measured one of the mercedes fans I have in the garage. It was 3.25-3.5". It also wasn't mounted to a radiator, so there may have been some tricks to shave off some height.

I've also tested the controller with a couple aftermarket fans, and it works just fine.

I measured my mercedes fan and got 3.125" I did have to use shorter allen head bolts to mount the water pump pulley.