SPRING 7I7239 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Illustration 1 g06143834
(A) 149-2835 Bolt
(B) 246-6762 Bevel Pinion
(C) 271-9167 Hub
(D) 6V-7742 Full NutBolts (A) and Nuts (D), which secure bevel pinion (B) to hub (C), may loosen during operation on certain 797 Off-Highway Trucks.Solution
Refer to Disassembly and Assembly, KENR8372, "Differential and Bevel Gear - Assemble" for information to assemble the differential and bevel gear.When reassembling the differential and bevel gear, the following items must be considered:
After bevel pinion (B) has been heated to 71° C (160° F) and seated onto hub (C), a minimum of 12 hours must elapse before the tighten process.
Ensure that all bolts, nuts, and washers are replaced during each overhaul
Apply sufficient Loctite 243 (blue) to bolts (A). Shake the product thoroughly before use. Fully cover the thread engagement length of the exterior threads that will engage with the interior threads. Torque procedures shall be completed within 10 minutes of insertion of threads.
Do not use red Loctite 277, or equivalent
Do not use any lubricant
Illustration 2 g06140016
First torque pattern
When first tightening nuts (D), use a cross pattern for nuts 1-4, as shown in Illustration 2 and torque to 200 50 N m (148 37 lb ft).
Illustration 3 g06140053
Second torque pattern
When tightening nuts (D) a second time, use a circular pattern for nuts 1-27, as shown in Illustration 3 and torque to 530 70 N m (384 52 lb ft).Note: Use the same nut 1 for both tightening sequences.