upgrading MTH DCRU F-3 to Legacy

Well, but they aren't the same price, and they aren't the same function, and they aren't the same wiring.

ERR-Cruise- back EMF tachless- no motor sensor, no extra wiring, standardized connections. Outputs example like lighting and smoke are track power level TRIACs. Very backwards compatible with typical upgrade engines that had incandescent lights, already had can motors, no need for extra sensor or wiring.

Lionel Legacy (specifically RCMC)- requires matching flywheel encoder ring and sensor, additional wiring, typically LED outputs for lighting, and specific smoke units if you used one.

Legacy BEMC- can be tachless, but then requires the RCDR- and wiring, so it's more components and more wiring.

Yes, it can be done and some folks specialized in it, however, again, they are not the same price, not the same components, and Legacy typically needs some experience and knowledge to know what to buy, what is compatible.

Legacy RCMC, RCDR, BEMC, RSLITE documentation found here- excellent PDFs!!! https://ogrforum.ogaugerr.com/...47#70411412245343347

Thanks to both @Bruk and @gunrunnerjohn

Again, the gotcha is:

#1 Lionel does not often provide or list complete wiring harness systems for an engine via parts

#2 Legacy- can be very specific in compatibility and requirements, and part A does not work with part B because the serial data commands do not line up. In  other words, you may run into mismatches and compatibility problems when trying to make something custom.

So as an example with some searching.

A BEMC is $90 but that requires an RCDR to receive the TMCC/Legacy Radio signal so another $89, and you still have to make your own wiring harness system. So $180 in parts right off the bat.

An RCMC is a little easier setup IMO as a more or less all in one board, but again, then requires a motor tachometer flywheel and encoder PCB combination to be installed physically into your chassis and motor system- and any clearance or other problems that might cause? Again, the board is $149 list, the sensor is $35, but then you still need that flywheel and that encoder ring to retrofit to your motor. Using this Legacy F3 as an example https://www.lionelsupport.com/...Pennsylvania-6-85207

And, by leaving off the bluetooth and the IR downward LCS sensor, you don't have those features.

Meanwhile, list for ERR Cruise commander the last I checked was about $150

I will say this, if Lionel hadn't pulled the handful of LCP2 boards both used in Legacy and Lionchief Plus 2.0 recent products (previously the only ones listed in parts were programmed with Lionchief Plus 2.0 code) then it might be a different conversation. That was a true all in one board, that did have sounds in the LC+2.0 format, and if one was retrofitting- that was a nice platform. It gave you everything (bluetooth, TMCC/Legacy receiver, sound or could use external RSLite for sound).

But Lionel removed that from the parts listing from us, and so unless you have some inside connection to Lionel- that upgrade path is currently not viable to my knowledge.

If you're wanting to do this upgrade, I recommend the ERR stuff, it's easy to install.  You can, with a little work, modify the Cruise Commander for a tethered bridge and run four motors with it, I've done it a few times, and others have as well.  The ERR Railsounds Commander has decent F3 sounds available as well.