I agree in the designation of the D10 as an unofficial D10L in conversation. This being that D10 can also be used generically. Cat made a 621. Many people refer to this as a 621A even though it was just a 621. Later Cat came out with a 621B. If someone says 621 would you know specifically if they were talking about a 621 or a 621B or a 621E or a 621F or a 621G or an upcoming 621H? I have Caterpillar produced literature that refers to a 621 (23H) as a 621A. D10L would mean more to more people than the D10 84W. The lettering implies generation. Why know 621C or 621D? Because they ran the 621B until they updated the other products (631s, 651s) to E models. The D10 84W was closer to the generation of the D9L and D8L.
If you agree, then i am afraid to say you are wrong.
If someone was talking about a 621 then to me it would be a 621 with a V8 engine and an outboard rear axle retainer. If some one referred to a 621B to me it would be a 3406 equipped machine, i am sorry but to me it is that simple, that is why they have a letter designation to identify them after the first model which if it is given any designation it would be as you say an "A" model, therefore if anything the 84W D10 should really be refered to as a "D10A".
The lettering and generation thing is drawing a long bow in the Case of "L"lettered tractors, the only reason the D9 & D8 had it is because it was a natural progression from there last models, the D10 never had a last model so it can not be an "L"
At the end of the day if you go by Cat,s numbering system there can be no confusion as to what is what, it is only when people dream up there own stuff that it gets all &^%$#@ up.
Very much like a track loader always being called a Drott, an artic truck being called a Moxy and a skid steer loader being called a Bobcat. It is just bull$hit and we should be educating people not letting them go off and be wrong because they heard someone else say it.
Flame away.
