2002/06/24 Caterpillar

Correction to Testing and Adjusting , "Transmission Hydraulic Control Primary Clutch Pressure - Test and Adjust" {3167}

Usage:

776D AFS

Off-Highway Truck/Tractor: 776D (S/N: AFS1-UP) 777D (S/N: AGC1-UP) 777D HAA (S/N: AGY1-UP)

Testing and Adjusting, RENR3320, "776D, 777D and 777D HAA Tractor/Off-Highway Trucks Power Train", "Transmission Hydraulic Control Primary Clutch Pressure - Test and Adjust". This module is part of Service Manual, RENR3330.

Disregard Table 31. Disregard Illustration 97. Disregard Table 32. Disregard Table 33. Refer to the following information.

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Table 31
Primary Clutch Pressure
Station ⁽¹⁾		"A"	"B"	"C"	"E"	"F"	"G"	"H"
Clutch		No. 4	No. 2	No. 1	No. 5	No. 6	No. 7	No. 3

Speed Position	Engaged Clutches	Pressure	Pressure	Pressure	Pressure	Pressure	Pressure	Pressure
NEUTRAL-1	1	0	0	345 kPa (50 psi) ⁽²⁾	0	0	0	0
NEUTRAL-2	1	0	0	345 kPa (50 psi) ⁽²⁾	0	0	0	0
REVERSE	1 and 7	0	0	345 kPa (50 psi) ⁽²⁾	0	0	415 kPa (60 psi) ⁽²⁾	0
FIRST	2 and 6	0	275 kPa (40 psi) ⁽²⁾	0	0	415 kPa (60 psi) ⁽²⁾	0	0
SECOND	1 and 6	0	0	345 kPa (50 psi) ⁽²⁾	0	415 kPa (60 psi) ⁽²⁾	0	0
THIRD	3 and 6	0	0	0	0	415 kPa (60 psi) ⁽²⁾	0	550 kPa (80 psi) ⁽²⁾
FOURTH	1 and 5	0	0	345 kPa (50 psi) ⁽²⁾	345 kPa (50 psi) ⁽²⁾	0	0	0
FIFTH	3 and 5	0	0	0	345 kPa (50 psi) ⁽²⁾	0	0	550 kPa (80 psi) ⁽²⁾
SIXTH	1 and 4	515 kPa (75 psi) ⁽²⁾	0	345 kPa (50 psi) ⁽²⁾	0	0	0	0
SEVENTH	3 and 4	515 kPa (75 psi) ⁽²⁾	0	0	0	0	0	550 kPa (80 psi) ⁽²⁾

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^( 1 )	Station "D" is not used.
^( 2 )	The tolerance is ± 40 kPa (± 6 psi).

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Illustration 1	g00877208
Pressure control valve (1) Selector piston plugs (seven) (2A) Modulation reduction valves (five) (2B) Modulation reduction valves (two) (3) Load piston orifices (seven) (4) Decay orifice plugs (seven) (5) Shims (seven places) (6) Load piston plugs (seven) (7) Inner springs (seven) (8) Outer springs (seven) (9) Load piston (10) Selector piston (A) (B) (C) (D) (E) (F) (G) (H) Pressure taps (identification for the load pistons)

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Table 32
Specifications and Identification of the Components of the Pressure Control Valve
Location of the Load Piston Body ⁽¹⁾	A	B	C	E	F	G	H
Thickness of the Load Piston Orifice	2.54 mm (0.100 inch)	2.54 mm (0.100 inch)	2.54 mm (0.100 inch)	4.58 mm (0.180 inch)	4.58 mm (0.180 inch)	4.58 mm (0.180 inch)	4.58 mm (0.180 inch)
Color of the Outer Spring of the Load Piston	Light Blue	Yellow	Light Green	Yellow	Yellow	Light Green	Light Green
Color of the Inner Spring of the Load Piston	Yellow	Light Blue	Light Blue	Light Blue	Light Blue	Yellow	Orange
Size of the Decay Orifice	1.57 mm (0.062 inch)	1.19 mm (0.047 inch)	-	1.57 mm (0.062 inch)	1.57 mm (0.062 inch)	-	1.40 mm (0.055 inch)
Color of the Decay Orifice	Green	Blue	-	Green	Green	-	Yellow
Overall Length of the Load Piston	58.5 mm (2.30 inch)	51.5 mm (2.03 inch)	51.5 mm (2.03 inch)	51.5 mm (2.03 inch)	51.5 mm (2.03 inch)	51.5 mm (2.03 inch)	58.5 mm (2.30 inch)

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^( 1 )

The location of the load piston body is identical to the location of the station for the valve. Station "D" is not used.

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Table 33
(7) Shims for the Pressure Control Valve
Valve Location ⁽¹⁾	A	B	C	E	F	G	H
Clutch that is engaged	4	2	1	5	6	7	3
The thickness of the shim	Pressure Change	Pressure Change	Pressure Change	Pressure Change	Pressure Change	Pressure Change	Pressure Change
5J-2721 Shim
0.13 mm (.005 inch)	13 kPa (1.9 psi)	16 kPa (2.4 psi)	20 kPa (2.9 psi)	17 kPa (2.4 psi)	17 kPa (2.4 psi)	18 kPa (2.7 psi)	18 kPa (2.6 psi)
6J-3993 Shim
0.25 mm (.010 inch)	26 kPa (3.8 psi)	33 kPa (4.8 psi)	41 kPa (5.9 psi)	33 kPa (4.8 psi)	33 kPa (4.8 psi)	37 kPa (5.4 psi)	35 kPa (5.1 psi)
4M-1751 Spacer
0.40 mm (0.016 inch)	42 kPa (6.1 psi)	53 kPa (7.7 psi)	65 kPa (9.4 psi)	53 kPa (7.7 psi)	53 kPa (7.7 psi)	59 kPa (8.6 psi)	56 kPa (8.2 psi)
5J-1036 Shim
0.80 mm (0.032 inch)	84 kPa (12.2 psi)	103 kPa (15.0 psi)	126 kPa (18.2 psi)	103 kPa (15.0 psi)	103 kPa (15.0 psi)	1144 kPa (16.6 psi)	109 kPa (15.8 psi)