Milton CAT 374D L - Manual (Page 8)

8
Undercarriage
The link that transmits the reaction forces from digging to the ground
Undercarriage
The undercarriage supports the swing bearing and upper structure and is the link that transmits
the reaction forces from digging to the ground. The strength of the undercarriage plays a major factor
in machine stability and durability.
Track Roller Frame
The track roller frame has been improved by installing a longer stroke recoil spring and lowering
the front idler. The longer recoil spring improves durability and service life of the undercarriage while
the offset idler increases the stability of the machine while working over the front.
Positive Pin Retention 2 (PPR2)
Track links with the PPR2 are provided as standard on the 374D L. The PPR2 track link is designed
to prevent looseness of the track pin in the track link and to reduce stress concentrations. The PPR2
system eliminates pin walking for increased service life.
Carrier Rollers
The carrier rollers use a floating “Duo-Cone” seal. The Duo-Cone seal protects the moving parts
in the carrier roller from water and dirt, and makes lubrication maintenance-free.