I've got a Fleischmann 5297 heavy load freight car, which has 8 axels, 4 at each end, which I want to run in freight trains on my layout.



For S88 detection to work, I'm thinking of replacing the DC wheelsets it has on it now, with AC wheelsets. But thats 8 wheelsets.

So one option, rather than spending $30+ to get 8 wheelsets, is to instead only replace some of the DC wheelsets, such as 2 of the axels (one at each end) or 4 of them (on at each end of the cars groups):

So go from
D D D D --------------------- D D D D

to
A D D D -------------------- D D D A
A D D A -------------------- A D D A

Where D is a DC wheelset, and A is an AC wheelset.

Now having read that differences may not just be the current conduction side to side, but also the spacing and other physical rolling dimensions, I've got the question, will replacing only some of the wheelsets, so having a mix of AC and DC wheelsets on the car, cause problems?

Well this just got a lot more interesting.
First there was the need to disassemble the wheel bogies from the car and bend some metal tabs to get the wheel sets out. Needless to say I'm only reinstalling once I have the wheels in hand to limit bending those small two tabs.

Then there turn out to be two different sizes of axels and styles on the car. Each end has 4 axels. The outer two on each end (the ones I'd planned to replace with AC wheelseta, have the sharp pint on them and ride inside a tight well the way one expects. Those are 23.91 mm in axel length. So 24mm. The inner two axels are looser without the ends being as captive my the wagon frame and longer and have a flat end to the axels. They are 27.06mm long. So 27mm.



So I need four 24 mm wheelsets to do the job.
Replacing all eight wheelsets would not be possible I think.