HIGH TRANSFER CASE SHIFT EFFORT REPAIR PROCEDURE

VEHICLES AFFECTED: 1988-89 K1, K2, K3 W/NEW PROCESS 241 TRANSFER CASE

High transfer case shift effort may occur when attempting to shift the transfer case from 2HI to 4HI in cold weather (below 4 DEG C (25 DEG F). In order to shift into 4HI the speed of the front propshaft must be increased significantly in order to synchronize the front axles for engagement. This may result in a high shift effort.

To reduce the shift effort, regular production front axle gear lube may be replaced with a synthetic 75W90 gear lube which has a lower viscosity in cold weather conditions. This results in greatly reduced shift effort. One such lube for Canada is Petro Canada, part number 4704780. Front axle lube capacities are 1.66 liters for K1 and K2 trucks and 2.13 liters for K3 trucks.

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