I have a Merc W163 ML500 which uses a A1635450416 control unit and a A0044310412 hydraulic unit for the ABS. If I replace both units , can I use a A1635459832 control unit and an A1634311312 hydraulic unit ?

 

Please UPDATE YOUR PROFILE in USER CP to include the year and where you live.

Also post your full vin#.

Why do you want to change these components?

 

I am guessing, your current ABS unit is failing? The ABS units are starting to fail on the W163s as they are getting into their 12-20 year lifespan...I just had it fail on my 2000 ML320 at 225,000 miles...
If that is indeed the case, you can get an exact replacement rebuilt module and a core credit from one of several rebuild shops...
Here is one, that does it for around $450ish..including shipping...
https://www.shop.modulerepairpro.com/

I just got mine done 2 months ago...extremely happy so far...

 

You should consider rebuilding it, if possible. There are hundreds of threads and many youtube videos on this for your year of vehicle, including links on where to buy the exact brushes and bearings. I think most people are simply replacing the brushes.