2003/10/06 Caterpillar

Use 1U-9891 Hydraulic Oil Additive to Eliminate Brake Chatter and Reduce Noise in the Limited Slip Differential {3263, 5095}

Usage:

980C 13B

Articulated Truck: D20D (S/N: 9MG1-UP); D250D (S/N: 6NG1-UP); D250E (S/N: 5TN1-UP); D25D (S/N: 1HK1-UP); D300D (S/N: 5MG1-UP); D300E (S/N: 7FN1-UP); D30D (S/N: 3AJ1-UP; 1PK1-UP); D350D (S/N: 9RF1-UP); D350E (S/N: 9LR1-UP); D400D (S/N: 8TF1-UP; 4EJ1-UP); D400E (S/N: 2YR1-UP); D40D (S/N: 2JJ1-UP)
Compact Wheel Loader: 914G (S/N: 7ZM1-UP; 9WM1-UP)
Integrated Toolcarrier: IT12B (S/N: 1KF1-UP); IT12F (S/N: 1KF1-UP); IT14B (S/N: 3NJ1-UP); IT14F (S/N: 4EL1-UP); IT14G (S/N: 8ZM1-UP; 1WN1-UP); IT24F (S/N: 4NN1-UP; 6KN1-UP); IT28F (S/N: 1JL1-UP; 3CL1-UP); IT28G (S/N: WAC1-UP; 8CR1-UP; 9AR1-UP; DBT1-UP); IT38F (S/N: 6FN1-UP; 5DR1-UP); IT38G (S/N: 7BS1-UP; 1CW1-UP); IT38G Series II (S/N: JAN1-UP; CSX1-UP); IT38H (S/N: JNJ1-UP); IT62G (S/N: AKP1-UP; 6PS1-UP); IT62G Series II (S/N: AYA1-UP); IT62H (S/N: M5G1-UP)
Landfill Compactor: 816F (S/N: 5FN1-UP; BMR1-UP); 826C (S/N: 87X1-UP); 826G (S/N: 7LN1-UP); 826G Series II (S/N: AYH1-UP); 826H (S/N: AWF1-UP); 836 (S/N: 7FR1-UP); 836G (S/N: BRL1-UP; 7MZ1-UP); 836H (S/N: BXD1-UP)
Soil Compactor: 815F (S/N: BKL1-UP; 1GN1-UP); 825C (S/N: 86X1-UP); 825G (S/N: 6RN1-UP); 825G Series II (S/N: AXB1-UP)
Wheel Dozer: 814F (S/N: BGF1-UP; 9DM1-UP); 824C (S/N: 85X1-UP); 824G (S/N: 4SN1-UP); 824G Series II (S/N: AWW1-UP); 824H (S/N: ASX1-UP); 834B (S/N: 7BR1-UP; 92Z1-UP); 834G (S/N: BPC1-UP; 6GZ1-UP); 844 (S/N: BBN1-UP; 2KZ1-UP); 844H (S/N: BTW1-UP); 854G (S/N: AMP1-UP; 1JW1-UP); 854K (S/N: 2211-UP; H9K1-UP; H8M1-UP)
Wheel Loader: 910E (S/N: 1SF1-UP); 910F (S/N: 1SF1-UP); 924F (S/N: 4YN1-UP; 5NN1-UP; 6MN1-UP; 7PN1-UP); 924G (S/N: DDA1-UP; RBB1-UP; WMB1-UP; AAN1-UP; 9SW1-UP; 3PZ1-UP); 924GZ (S/N: RTA1-UP; AAB1-UP; 6YW1-UP; WGX1-UP; DFZ1-UP; 3DZ1-UP); 928F (S/N: 8AK1-UP; 2XL1-UP; 7YM1-UP); 928G (S/N: DJD1-UP; WLG1-UP; 6XR1-UP; 7SR1-UP); 936F (S/N: 8AJ1-UP; 4TK1-UP; 9MK1-UP); 938F (S/N: 1KM1-UP; 2RM1-UP; 8SM1-UP; 7SN1-UP); 938G (S/N: 4YS1-UP; 6WS1-UP; 8RS1-UP; 9HS1-UP); 938G Series II (S/N: RTB1-UP; CRD1-UP; PHN1-UP; B9Y1-UP); 938H (S/N: MJC1-UP; JKM1-UP; LKM1-UP); 950F (S/N: 7ZF1-UP; 6YG1-UP); 950F Series II (S/N: 4DJ1-UP; 5SK1-UP; 8TK1-UP; 2LM1-UP); 950G (S/N: 2JS1-UP; 4BS1-UP; 6NS1-UP; 3JW1-UP; 5FW1-UP; 5MW1-UP; 8JW1-UP); 950G Series II (S/N: BAA1-UP; AYB1-UP; AYD1-UP; AYL1-UP; AXR1-UP; AYS1-UP; AXX1-UP); 950H (S/N: N1A1-UP; M1G1-UP; J5J1-UP; K5K1-UP); 960F (S/N: 9ZJ1-UP; 4CL1-UP; 6XL1-UP; 1YM1-UP); 962G (S/N: BDP1-UP; 3BS1-UP; 5AS1-UP; 5RS1-UP; 9BS1-UP; 4PW1-UP; 6EW1-UP; 6HW1-UP; 7BW1-UP); 962G Series II (S/N: BAB1-UP; BAC1-UP; BAD1-UP; AYE1-UP; AYG1-UP; AXS1-UP; AXY1-UP); 962H (S/N: N4A1-UP; M3G1-UP; J6J1-UP; K6K1-UP); 966F (S/N: 4YG1-UP; 8BG1-UP; 3XJ1-UP; 1SL1-UP); 966F Series II (S/N: 9YJ1-UP); 966G (S/N: AAH1-UP; HDH1-UP; 3ZS1-UP; 9RS1-UP; 3PW1-UP; 3SW1-UP; 8XW1-UP); 966G Series II (S/N: AXJ1-UP; AXL1-UP; ANT1-UP; AWY1-UP; ANZ1-UP; AWZ1-UP); 966H (S/N: A6D1-UP; A6G1-UP; A6J1-UP; FMW1-UP); 970F (S/N: 7SK1-UP; 9JK1-UP; 7PL1-UP); 972G (S/N: 7LS1-UP; AAW1-UP; 1EW1-UP; 4WW1-UP; 6AW1-UP; 9GW1-UP); 972G Series II (S/N: AXC1-UP; AXE1-UP; AXN1-UP; AWP1-UP; AXP1-UP; ANY1-UP); 972H (S/N: WLA1-UP; A7D1-UP; A7G1-UP; A7J1-UP); 980C (S/N: 13B1-UP; 2XD1-UP; 63X1-UP); 980F (S/N: 8CJ1-UP; 3HK1-UP); 980F Series II (S/N: 5XJ1-UP; 4RN1-UP; 8JN1-UP); 980G (S/N: 9CM1-UP; 2KR1-UP; 2SR1-UP); 980G Series II (S/N: AXG1-UP; AWH1-UP; AYT1-UP); 980H (S/N: MHG1-UP; A8J1-UP; JMS1-UP); 988B (S/N: 50W1-UP); 988F (S/N: 8YG1-UP); 988F Series II (S/N: 2ZR1-UP); 988G (S/N: BNH1-UP; 2TW1-UP); 988H (S/N: BXY1-UP); 990 Series II (S/N: BCR1-UP; 4FR1-UP); 990H (S/N: BWX1-UP); 992 (S/N: 25K1-UP); 992B (S/N: 25K1-UP); 992C (S/N: 42X1-UP; 49Z1-UP); 992D (S/N: 7MJ1-UP); 992G (S/N: 7HR1-UP; ADZ1-UP); 992K (S/N: 8801-UP; H4C1-UP; ZMX1-UP)

Service Magazine, SEPD1501, 26, September 2012, "Use 1U-9891 Hydraulic Oil Additive to Eliminate Brake Chatter and Reduce Noise in the Limited Slip Differential". Disregard this article. The correct information follows.

Reference Material

Service Magazine, SEPD0371, 28, July 1997, "Differential Oil Changes Require 1U-9891 Hydraulic Oil Additive"
Service Magazine, SEPD0332, 11, November 1996, "Hydraulic Oil Additive Used That Eliminates Noise In Differentials"
Service Magazine, SEPD0174, 27, September 1993, " 1U-9891 Hydraulic Oil Additive Eliminates Noise From Enclosed Brakes"
Service Magazine, SEPD0122, 17, August 1992, " 1U-9891 Hydraulic Oil Additive Eliminates Noise From Final Drives"
Service Magazine, SEBD1992, 13, November 1989, " 1U-9891 Hydraulic Oil Additive Available To Quiet Noise From Limited Slip Differentials"

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NOTICE

1U-9891 Hydraulic Oil Additive is a friction modifier. Use of the additive will lower the static coefficient of friction between mating parts. Do not use this additive in compartments without approval from Caterpillar. If the use of 1U-9891 Hydraulic Oil Additive is approved by Caterpillar, use only as directed.

Note: 1U-9891 Hydraulic Oil Additive, 185-4771 Hydraulic Oil Additive, and 9U-7062 Hydraulic Oil Supplement are different part numbers because requirements need individual part numbers, but all the part numbers are the same field service product. Each bottle is 0.95 L (1 qt).

Normal brake chatter does not cause extra wear. Chatter is a vibration. If the static coefficient of friction of the brakes is greater than the dynamic coefficient of friction, chatter is caused. Chatter occurs with newer brakes as the machine is approaching a stop. The 1U-9891 Hydraulic Oil Additive minimizes normal brake chatter by reducing the static coefficient and maintaining the dynamic coefficient. In time, the brake coefficient will change. Then, the normal braking chatter will be eliminated. Because the time for elimination of the chatter cannot be predicted, use of the additive is recommended at every oil change of the axle.

The same coefficient conditions that are described above will cause a limited slip differential to make noise. The noise does not cause extra wear. The addition of the recommended amounts of additive at every oil change of the axle will reduce the noise. The noise will not be eliminated.

The following table shows the recommended minimum amount of additive to use for each specific model. Production machines are presently shipped from the factory with the minimum amounts. Extra additive may be required for the differences in oil volume or for changes in the condition of the oil.

Note: Do not exceed three times the recommended amount of oil additive that is noted in the table. Apply 0.47 L (0.5 qt) per axle on an hourly basis until the chatter stops. Using more than three times the amount will only dilute the chemistry of the oil. Also, using more than three times the amount of 1U-9891 Hydraulic Oil Additive may break down the viscosity of the oil.

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NOTICE

Do not use the additive for brake chatter without checking the machine for a more serious problem.

Refer to the following list of potential serious problems that may cause brake chatter.

Water or antifreeze in the axle oil Concentrations of 0.5% or greater can significantly raise the static coefficient of friction of the brakes. This static coefficient of friction may cause chatter. Concentrations of 0.5% or greater can cause swelling of the brake friction material and separation from the discs core. Drain the compartment and flush the compartment as soon as possible. Monitor brake disc wear and watch for elevated iron in the S·O·S Oil Analysis.
Degradation of axle oil If the oil is used beyond the wear life, the friction modifiers may be depleted. This depletion may initiate brake chatter. Oil degradation can result in rapid brake wear and the reduction in protection of the oil film thickness for the gears and the bearings. Wear life of the oil will vary depending on the application and operator techniques. Monitor the levels of contaminant in the oil. Monitor the oil condition by using S·O·S Oil Analysis to develop the best oil change interval for the machine. Never use oil beyond the scheduled maintenance interval that is recommended by Caterpillar.
Axle oil can become oxidized or burnt. When oil becomes oxidized, the friction modifiers are depleted. This depletion of friction modifiers may cause brake chatter. Excessive oil temperatures will produce rapid brake wear and reduced protection in oil film thickness for gears and for bearings. Correct the problem that is producing excessive oil temperature, or change the axle oil more frequently to sustain good oil condition.
Brake discs worn beyond maximum allowable condition. When the friction material of the brake disc is worn to the bonding material or the core, the coefficients significantly change. This change will increase the probability of brake chatter.
Unapproved oil Gear lube is one example of unapproved oil. Most gear lube contains extreme pressure additives. Extreme pressure additives that are combined with elevated brake temperatures can glaze the surface of the friction material. As a result, the dynamic coefficient is reduced and the probability of chatter is increased. Drain and flush the compartments. Remove all gear lube. Replace the wheel brake friction pad with a new pad.

Another example of unapproved oil is Final Drive Oil for the Axle. 1U-9891 Hydraulic Oil Additive will not effectively eliminate brake chatter if the FDAO is mistakenly used.

Reference: Refer to the machine Operation and Maintenance Manual for the correct oil, or Special Publication, SEBU6250, "Caterpillar Machine Fluid Recommendations" for additional information.

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Table 1
Sales Model	Amount of Additive per Axle
Wheel Loaders
910E, 910F, 910G, 914G	0.47 L (0.5 qt)
924F, 924G, 924GZ	0.47 L (0.5 qt)
928F, 928G	0.47 L (0.5 qt)
936F, 938F, 938G, 938G II, 938H	0.47 L (0.5 qt)
950F, 950F-II, 950G, 950G II, 950H	0.47 L (0.5 qt)
960F, 962G, 962G II, 962H	0.47 L (0.5 qt)
966F, 966F II, 966G, 966G II, 966H	0.95 L (1.0 qt)
970F, 972G, 972G II, 972H	0.95 L (1.0 qt)
980C, 980F, 980F II	1.42 L (1.5 qt)
980G, 980G II, 980H	1.42 L (1.5 qt)
988B, 988F, 988F II, 988G, 988H	2.8 L (3.0 qt)
990, 990 II, 990H	3.8 L (4.0 qt)
992B, 992C, 992D	3.3 L (3.5 qt)
992G, 992K	4.7 L (5.0 qt)
Integrated Toolcarriers
IT12B, IT12F, IT14B, IT14F, IT14G	0.47 L (0.5 qt)
IT24F, IT28F, IT28G	0.47 L (0.5 qt)
IT38F, IT38G, IT38G II, IT38H	0.47 L (0.5 qt)
IT62G, IT62G II, IT62H	0.47 L (0.5 qt)
Wheel Dozers and Compactors
814F, 815F ⁽¹⁾, 816F ⁽¹⁾	0.95 L (1.0 qt)
824C, 824G, 824G II, 824H	1.4 L (1.5 qt)
825C ⁽¹⁾, 825G ⁽¹⁾, 825G II ⁽¹⁾.	1.4 L (1.5 qt)
826C ⁽¹⁾, 826G ⁽¹⁾, 826G II ⁽¹⁾, 826H ⁽¹⁾	1.4 L (1.5 qt)
834B, 834G	2.8 L (3.0 qt)
836 ⁽¹⁾, 836G ⁽¹⁾, 836H ⁽¹⁾	2.8 L (3.0 qt)
844, 844H	3.8 L (4.0 qt)
854G, 854K	4.73 L (5.0 qt)
Articulated Trucks
D20D, D250D, D250E, D25D, D300D, D300E, D30D, D350D, D400D, D40D	0.47 L (0.5 qt)
D350E, D400E	0.95 L (1.0 qt)