FRAME GP-UPPER 3832374 - Caterpillar

Sealed And Lubricated Track
The D4H Custom Skidder with 18" shoes is a standard track group for D4H LGP Tractors. The D5H Custom Skidder with 20" shoes requires a special 42-section track group. Custom skidders requiring wider shoes than those mentioned above must use quad link track.
Quad Link Track
The shoe widths requiring quad link track are 23" and 30" for the D4H Custom Skidder and 26" and 32" for the D5H Custom Skidder. These skidders have increased loading and severe operating conditions, which require the quad link. See charts for correct part number for link assemblies and track shoes.
Illustration 1. Quad link track.The quad link track offers the following features and benefits: ...An additional single rail link assembly is bolted near each end of the shoes to distribute the concentrated loads to several shoes and the center link assembly. This reduces dry joints, bore stretching, link cracking, and shoe bolt loosening....Undercarriage life is increased in severe applications where service and replacement is required before normal track wearout. This reduces cost per hour for the undercarriage.
Center Link Assemblies
The center link assembly is the same as the link assembly on a standard sealed and lubricated track assembly.
Outboard Link Assembly
Existing links with sealed joints for Series H Tractors are used on the outboard link assemblies. The pin is similar to a sealed track pin, except it is shorter. The bushing is a shorter version of a bushing for a Series H Tractor. An additional seal plug is added to the bushing to close the open end of the bushing (see Illustration 2).The outboard links of a quad link can be built using any worn D4H and D5H links on the outboard sides, since no further rail wear occurs on these links.
Illustration 2. View A from Illustration 1.Shoes
Special track shoes are needed for the quad link track. These have two additional pairs of bolt holes and clearance notches. Existing D4H and D5H standard track shoes can be retrofitted by drilling outboard holes and cutting clearance notches for the outboard links.
Idlers
Due to the high rear loading custom skidders, accelerated rear idler wear can be expected. The idlers can be swapped if they meet the criteria stated in the CTS (Custom Track Service) Handbook on page 52. See the parts list for the correct idler part numbers.
Sprocket Segments
D4H Custom Skidders use the same segments as D4H and D4H LGP Tractors. D5H Custom Skidders use a special five-tooth segment. See the parts lists for the correct segment part numbers.
Track Rollers
Standard track rollers are used. The configuration is the same for both D4H and D5H Custom Skidders. Refer to Illustration 3 for the correct placement of single (S) and double (D) flange rollers. Use all double flanged rollers if improved track guiding is required.
Illustration 3. Location of track rollers.Carrier Rollers
Custom skidders do not require carrier rollers.
Track Sag
Track sag should be measured and adjusted as specified in reference IRM UC 88-5. Correct track sag is 75 10 mm (3.0 .4").
Track Roller Guards
Always use full-length track roller