General instructions, Further information, Specifications – SkyTrak 3606 Service Manual User Manual
Page 128: Serial number plate, Technical data, Transfer case, Transfer case inspection and service

Section 6
6-4
6.1
GENERAL INSTRUCTIONS
IMPORTANT:
To help ensure optimum performance, the
drive shaft assemblies are specially balanced as a unit at the 
factory. When servicing any flange yoke, slip yoke or drive shaft 
tube, order a complete assembly if components are bent or 
damaged. Refer to the Sky Trak International Model 3606 Parts 
Manual for ordering information.
Before performing any inspection, maintenance or service 
operation, thoroughly clean the unit. The transfer case and 
drive shafts should be checked and repaired only by expe-
rienced service technicians who are aware of all safety 
instructions and particular component features.
Use suitable products to thoroughly clean all disassem-
bled mechanical parts to help prevent personal injury to 
the worker and damage to the parts. Carefully inspect the 
integrity of all moving parts (bearings, yokes, tubes, 
gears, shafts, etc.) and fasteners (nuts, bolts, washers, 
etc.) as they are subject to major stress and wear. Always 
replace elastic-lined nuts and any damaged, worn, 
cracked, seized, or otherwise improper parts that could 
affect the safe and proper functioning of the vehicle, 
transfer case and drive shafts.
6.1.1 Further Information
Detailed transfer case service instructions covering 
repair, disassembly, reassembly, adjustment and trouble-
shooting information is provided in the Carraro Model TB 
420 Transfer Box Maintenance and Repair Manual, Carraro 
part number CA355026.
6.2
SPECIFICATIONS
Refer to Section 2 General Information, Specifications 
and Maintenance Instructions.
6.2.1 Serial Number Plate
The Carraro serial number plate is riveted to the rear of 
the transfer case above the center of three cover plates. 
Information specified on the serial number plate includes 
Drop Box Type (TB 420), Serial Number, Carraro refer-
ence number, Oil Specific (oil type), and Ratios (final 
gear ratio, 1:1). Write this information down in a conve-
nient location to use in transfer case correspondence.
Figure 6–1. Location of Carraro serial number plate.
6.2.2 Technical Data
1. Transfer Case Type:
Carraro Model TB 420
2. Description:
Single-speed transfer case
3. Forward Reduction Ratio:
1:1
4. Reverse Reduction Ratio:
1:1
5. Total Reduction Ratio:
1:1
6. Parking Brake (front axle):
Spring applied, hydraulic
release, wet-brake disc type
7. Input Rotation:
Reversible; clockwise and
counter-clockwise
8. Maximum Input RPM:
3,000
9. Oil Capacity:
1.5 quarts (1,425 liters)
10. Oil Type:
SAE 80W90 EP or 80W140,
to comply with API GL4,
API GL5 (respectively),
MIL-L-2105 and MIL-L-2105D
Specifications
11. Dry Weight:
N/A
12. Bearing Preload:
125-130 lb/ft (55-59 Nm),
measured without oil seal
ring fitted
(NOTE: Transfer case shaft bearing adjustment procedures 
are not covered in this manual. Refer to the Carraro Model 
TB 420 Transfer Box Maintenance and Repair Manual, 
Carraro part number CA355026.)
13. Sealing Compounds:
Loctite
®
518, 540, 638
6.3
TRANSFER CASE
6.3.1 Transfer Case Inspection and Service
Whenever servicing the vehicle, conduct a visual inspec-
tion of the transfer case. A few moments spent doing this 
can help prevent further problems and down time later.
Inspect the transfer case in its entirety, especially the 
main casting, for any cracks, dents, or other damage. 
Look for oil seepage or leaks around the drive shaft 
flange mounts. Check all bolts for proper torque.
While the vehicle is under warranty, Sky Trak Interna-
tional does not recommend the servicing of gears, shafts 
or bearings inside the transfer case. Attempts at disas-
sembly of these internal transfer case items may void the 
warranty, cause damage to other parts and to the transfer 
case casting (housing) itself. If internal service of the 
transfer case is required while still under warranty, return 
it to Sky Trak International for replacement with a new 
transfer case pursuant to the Sky Trak International war-
ranty and return policy in effect when the vehicle was 
purchased.
If service of internal transfer case components is required 
and the transfer case is not under warranty, refer to the 
Carraro Model TB 420 Transfer Box Maintenance and 
Repair Manual, Carraro part number CA355026, or con-
sult an authorized Carraro repair center or dealer.
Serial number plate
Front of vehicle
Rear of transfer case
MS0440
Model 3606 • Origin 10/99
