Numbering conflicts

Do railroads usually avoid giving the same number to a piece of rolling stock and a locomotive?

MMA 100 is a GP7. http://www.rrpicturearchives.net/showPi ... ?id=392948
MMA 100 is a boxcar. http://www.rrpicturearchives.net/showPi ... ?id=577513

Nope cars and locomotivesare two diffrent things and will be numbered in the order of which the that railroad prefers to number them.

Now Railroads will avoid giveing the same number to two Locomotives or 2 railroad cars which has happened a good many times with all the mega mergers that have taken place in the last 30 years or so.

I have also seen a few close ones with cars being almost being mirror images of each outher such as CP/SOO Hoppers 908098 and 909098 being coupled together the chance of that was more then likley 1 in a million to see them both at the same time in the same location.

In the case of a newly merged large railroad, often two different engines
might have the same numbers but they are still lettered for different
railroads as well. Before these engines get a re-lettering, they will have
to be renumbered.
Case in point, when the Penn Central took over the New Haven Railroad
the FL-9's were numbered 2000-2059 but this number series conflicted
with some former New York Central Alco's so the FL-9 got renumber to
the 5000-5059 series quite quickly but it took a bit of time, they were all
renumbered before they were relettered.
Noel Weaver

There have been a very few rare instances where through a painter's error, there were two cars with identical initials and numbers. I vaguely recall seeing one such instance in an old RAILROAD magazine, and reading about another. This was back in the days of paper and pencil recordkeeping. Such a mistake would be far less likely to happen with today's computerized reporting.

About 25 years ago the shortline I was on received two cars with the same initial, but with 2 digits transposed. For example, 27548 and 27458. They were billed to two separate food processing plants. When the crew was done I found they had given the cars to the wrong customers because of the similarity. But as I was preparing to make panicked phone calls I looked at the waybills and saw that not only did each contain the same commodity from the same shipper, but the weights and quantity were identical. I called each plant and they agreed to just unload the car they had and call it even - which it was!

The same thing happened with Amtrak's F40s (which were being retired at the time), all of the Rohr Turboliners and some of the Amtrak's GP40 switching Engines which needed to be renumbered since that sequence (1-209) was needed for the then new P42DCs, so the Amtrak GP40s were renumbered to the 500-series, any Remaining F40s (converted to NPCUs) would have the 90 prefix installed before the original 200 or 300-series number (e g 214 would be 90214 and F40PH 368 would be NPCU 90368), and the RTL's were renumbered to the 2100-series (not to be confused with the Acela Express Train trip numbers).

Re my post above about occasional painter's errors, October 1968 TRAINS magazine has a photo on page 54 of two boxcars coupled together in a WP yard in San Francisco. Both are EL 50623. It states the cars arrived from different directions and caused a lot of confusion. Finally it was established there were duplicate numbers and initials, and the cars were switched together for a photo to prove the point.

Also in the R.R. Registry books they do make in point to double check car reporting marks and car numbers. Case in Point cars with PGE were not to confused with PG&E and there were two railroads that used the first letters THB in there begining of there names but only one used THB for reporting marks.