G-F-45 R01
PARTS-SERVICE
DATE: Oct. 22, 1974
MODEL: M600A
GRAM
STEERING
NOTE: The revision is only
to allow reissuing the gram.
It was cancelled in error.
No changes in content.
SUBJECT: STEERING - CORNER SUSPENSION
A new fork tube arrangement is available to service trucks used in excessively rough operations. The new
arrangement increases the service life of the corner suspension. Improvements in this design are listed:
1. Higher strength fork tube bushings.
2. Chromed fork tubes for wear resistance.
3. Knockout holes and a puller ledge in the bearing carrier for removal of the bearing cup.
4. Knockout holes in the upper bushing for removal of the bearing cone.
5. Snap ring retains upper bushing in the bearing carrier.
6. Quad rings replace the o-rings in the bearing carrier.
7. A grease seal is added to the lower bushing.
8. Two grease cups are added per corner for forced bearing lube of upper bearing.
9. A cover plate protects each corner bearing from foreign material.
Parts affected by this change are listed:
New Part Number Description Qty. Original P/N
191659 Lower Bushing - Fork Tube 4 75049
192544 Capscrew - 12 pt. 1/2 UNF X 2 32 16304
192538 Seal - Rod 4 -----
191647 Upper Bushing - Fork Tube 4 75050
191637 Quad - X Seal 4 18966
191643 Bearing Carrier 4 75051
191435 Quad - X Seal 4 18960
191434 Snap Ring - Internal -----
4
15483 P. Ftg. Plg. Ctsk. S-2 8 -----
192545 Cup - Lubrication -----
8
16001 L. Ftg. Str. Thd.2 8 -----
13960 L. Ftg. Str. Thd. 1/4 - 28 8 -----
NOTE: Part numbers for the new chromed fork tubes do not change. Use the same part numbers when ordering
fork tubes.
We reserve the right to make changes in design or add improvements without incur-
ring the obligation to make such changes in equipment previously manufactured.
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G-F-45 R01
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Steps for Installing New Arrangement:
A. Chrome the original fork tube according to the following directions (See also Figure III - Fork Tube
Alteration) or purchase a new fork tube.
1. Machine 12 3/4 long, to 9.758 maximum diameter and 13 long, to 8.256 maximum diameter. See
Figure III for dimension locations.
2. Build up sufficient weld material in these areas (use A.W.S. E90 18 B3 electrode) to obtain the
following machined diameters.
Machine 12 3/4 long to 9.868 maximum diameter (63-125 finish).
Machine 13 long to 8.366 maximum diameter (63-125 finish).
3. Chrome plate and grind and polish to the dimensions and finishes shown.
NOTE: This alteration applies to fork tubes with P/N 75118, 76614, 157741, 140335,
189938, 89415, and 163574.
B. Weld the 191433 cover plates to the front steering arms and rear driving heads according to Figure
II. Center the cover plate on the center line of the hole in the steering arm as dimensioned in
Figure II.
C. Assemble the corner according to the following directions: (See Figure I)
1. Place the 191659 lower bushing and the 192538 rod seal in position over the fork tube.
2. Place the fork tube into the frame corner and install the 192544 twelve point capscrews and
177949 lockwashers.
3. Place 1/2 inch of grease in the cavity above the lower bushing. Use a grease meeting the specifica-
tions stated in Figure V.
4. Place the 75123 spring seat, 75124 plate spacer and 75028 spring on the fork tube.
5. Check dimension X of all four corners. Add 75124 plate spacers so the total stack height of the
(75123 spring seat, 75124 plate spacers, and 75028 spring) shorter spring stacks are no more than
1/8 inch shorter than the longest spring stack.
6. Assemble the bearing assembly as a group before placing them on the fork tube. Place parts
230435, 230436, 191435, 191637, and 191647 in the 191643 bearing carrier. Pack the bearings
with grease having the specifications of Figure V. Check the 191435 and 191637 quad-X seals for
correct installation. Retain these parts in the bearing carrier by installing the 191434 snap ring.
7. Place the 192545 lubrication cups (two per corner) and the 15483 fitting in the 191643 bearing
carrier as illustrated in Figure IV.
8. Place the assembled bearing carrier on the fork tube and correctly index the lube cup by rotating the
bearing carrier. See the bottom of Figure IV for the correct position of the lube cup at each corner
of the truck.
9. Secure the bearing carrier to the frame with the 12482 capscrews and the 15162 lockwashers
(Figure I).
10. Place the 16001 lube fitting in the lube cup.
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Oct. 22, 1974
11. Lubricate these lube fittings:
a. 13960 lube fitting on the 191659 lower bushing.
b. 16001 lube fittings on the 192545 lube cup.
Use a grease that meets the specifications stated in Figure V.
12. The spring force in the lube cup which dispenses grease to the upper bearings is adjustable. The
knob on the outer end of the lube cup may be turned in to increase the rate that grease is dis-
pensed.
13. Lube the truck corners at least every 100 hours of truck operation.
Interchangeability:
Service old trucks prior to the effective serial number with old parts.
The new 191647 upper fork tube bushing and related parts [191643 bearing carrier (1), 191637 quad
seal (1), 191435 quad seal (1), 191434 snap ring (1), 15483 P. ftg. plg. ctsh (2), 192545 lube cup (2)]
must be used as an assembly only.
The new 191659 lower fork tube bushing must be used as an assembly with the new 192538 rod seal.
NOTE: The new 191647 upper bushing and 191659 lower bushing will give the best service life if
used with the chromed fork tube.
Parts Stock:
At the option of dealers, stock may be returned to the Parts Depot for credit of the part numbers 75049,
75050, 18966, 75051, and 18960. Form HY184Rl must be submitted to the depot within 90 days of the
date of this gram. Authorization must be received before parts are returned.
Effective Serial Number:
A14P-
Parts Reference:
Parts Book Microfiche
Form 934 R7, page K5 Grid F1, Card 2
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G-F-45 R01
Oct. 22, 1974
FIGURE I - Arrangement of Fork Tube Components
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Oct. 22, 1974
FIGURE II - Weldment, Cover Plate to Steering Arm
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Oct. 22, 1974
FIGURE III - Fork Tube Alteration
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G-F-45 R01
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FIGURE IV - Installation of Bearing Carriers and Lubrication Cups
Place the 191643 bearing carrier in each of the
frame corners indexed as shown below for
proper positioning of the 192545 lubrication
cup
NOTE: Use two (2) lubrication
cups in each bearing
carrier. Locate them at
the arrows of each
corner.
L.H. Rear Corner
R.H. Rear Corner
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G-F-45 R01
Oct. 22, 1974
FIGURE V  Grease Specifications For M600 Corner Lube
This grease must be compounded from a high grade lithium soap, a 2 to 4% micronized
molybdenum disulfide additive, and refined high grade mineral oil.
This is a multi-purpose grease generally intended for use as a chassis, universal joint,
and cup grease lubricant.
This grease must meet the following requirements.
N.L.G.I. No. 2
Dropping Point °F 340 (min.)
(ASTM D-566)
Oil Viscosity 750 (min.)
@ 100 °F SSU
Bomb Oxidation Test 10 psi (max.)
ASTM D-942 after 100 hours
Several possible sources for this type of grease are listed:
United States and Canada
Atlantic Richfield Company: Rocolube Moly D
Mobil Oil Corporation: Mobilgrease Special
Shell Oil Company: Lithal MDS Grease
Texaco Inc.: Molytex #2
Sun Oil Company: Prestige Moly Grease M3
Imperial Oil Ltd.: Esso MP Grease Moly
Citgo: Premium Moly Lithium #2 Grease
Gulf: Gulflex Moly Grease
Standard Oil Co. of California: RPM Moly Grease
Chevron Oil Co.
Sinclair Oil Corporation: Litholine EP Moly Grease
Australia
BP Australia Ltd.: BP Energrease LMS 22