So I checked out my operational reference guide. Info as follows
FDR Drive - because of weight limitations a light weight vehicle is used in place of an Engine Company to respond to fires and emergencies on portions of the FDR in manhattan. The FDR response vehicle at Engine 22 is a Ford F-450 flatbed with a removable Salsbury brush fire module. A second unit at engine 16 was de-activated in April of 2001. No backup company is designated.
Belt Parkway - Highway Response Vehicles (HRV) are in service with TL 159 and TL 170 because of weight restrictions on the Belt PKWY at the Paerdegat Bridge. The company officer and two firefighters respond with the HRV, the ladder does not enter the PKWY. Each utility type truck is equipped with Hurst and Rabbit Tools, Sawzall and Air chisel, partner saw, forceable entry tools, extinguishers, air bags and cribbing, stokes basket, 5kw generator and lights and three SCBA masks.
FDR Response Vehicle is a 1995 Ford F-450 with a Salsbury Brush Fire Module with a Shop Number of FM 9535 the unit retired in 2001 was identical.
The HRV's were originally 2000 GMC Sierra 3500HD's with Reading Body's, One is still serving as a SOC support unit, I am not sure if only HRV 159 is the only one in service or if HRV 170 was replaced by a Ford F-450 same set up as a SSL or CPC type vehicle. HRV 170 shop number GM 00020 is the one that was transferred to SOC to serve as support unit.