"D" in registration number

[mercurygrandmarquis1]

What does the D in the apparatus registration number mean?

 

[memory master]

What type of rig did you see this on?

 

[mercurygrandmarquis1]

it appears on the list of registration numbers. the newest ones with a D are the mid 90s Seagrave engines. also there are T's and H's which im also trying to figure out. (I know H on an engine means high pressure but there were a few trucks with H in the number).
http://nyfd.com/frontpage/shops.html

 

[lucky]

Could possibly be dual rear axles.

 

[R1SmokeEater]

Could possibly be dual rear axles.

D was for dual axle (prior deliveries were all single) now all are dual

T denotes Tiller

 

[downtownmedic]

The "D" was indeed for dual rear axles - no longer used.  The "H" on pumpers is for high-pressure - on ladder apparatus the "H" was for high ladder - specifically the 4 1989 and 1990 110' rear-mounts...the "T" on ladder apparatus is technically for TRAILER but is commonly used for tillered - you'll also see the "T" on the 1995 SuperVac trailers as well as some other trailers.