Usage:
768C, 772B Tractors;
769C, 773B Trucks
- SUPPLEMENT: 12/12/92
SERVICE MAGAZINE; NOVEMBER 28, 1988; PAGE 4; "Improved Wheel And Longer Bolts Provide Better Retention Of Front Brake Disc" on 768C, 772B Tractors and 769C, 773B Trucks. In the last sentence of the article, put a mark through 750 ± 60 lb ft. The correct tightening torque for the longer bolts is 750 ± 80 N·m (550 ± 60 lb ft).
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Description of Change: An improved wheel is used in the front wheel group and new longer bolts are used in the service brake group. The improved wheels have counterbored mounting holes for the front brake discs. The longer bolts and the improved wheels will permit more stretch of the bolts when they are tightened. This will result in better retention of the brake discs.
Adaptable To: The new 1D4627 Bolts, when used with the improved wheels, are a direct replacement for the former 9F9522 Bolts. The part numbers of the 6G6438 Wheel (772B, 773B) and 6G6439 Wheel (768C, 769C) did not change. Existing 6G6438 and 6G6439 Wheels can be modified for use with the longer bolts. See the illustrations. When the longer bolts are installed they should be tightened to 750 ± 60 lb ft).
Holes which need to be modified.
Section A-A.