Hmmm. Well...I think I now know enough that I am probably going to be safe by referring to those trucks with roller bearings as...well...roller bearing equipped trucks and those without roller bearings as..well...non roller bearing trucks.

OTOH, I forsee great difficulty in the future when I prepare to describe the type of bearings used on UP Big Boys. It is true that these engines had roller bearings associated closely with all tender and locomotive wheels [ notice how carefull I am now ], but they did not have roller bearings on the engine's rods [ gasp! ] instead using McGill needle bearings. To add to the problem, the engines suffered failures in the front engine's lubricator actuating rod, replacing it with a chain link drive. Regretfully, a small number of obscure narrow gauge locomotives used chain link drives to turn the drivers. My friend, the late Lou Ullian, actually had a model of one. Alas, imagine my dilemma...do I call a Big Boy a chain link drive engine, one with some roller bearings, one with McGill bearings or...maybe just a Big Boy?

Mike Brock...preparing to lose sleep tonight over this issue

At 06:53 PM 4/29/2012 -0400, you wrote:

Alas, imagine my dilemma...do I call a Big Boy a chain link drive engine,
one with some roller bearings, one with McGill bearings or...maybe just a
Big Boy?

I've always thought it slightly odd that no other road built a 4-8-8-4. I suppose had steam ruled for another decade, someone would have built one. Which may have caused it to have another name. Or maybe PRR would have built an 8-cylinder duplex 4-4-4-4-4-4 and called it a Pittsburger.

Andy