GM Halts Full-Size Truck Sales to Check Bearing Failures(Pic)

GM 4L80-E General Motors Corp. (USA) halted U.S. deliveries of its popular full-size pickup trucks, vans and sport utility trucks equipped with 4L80-E Hydra-Matic transmissions produced in its Willow Run plant. Approximately 25,000 trucks are affected. Bearings in the automatic transmission's overdrive fourth gear may be running dry due to faulty transmission oil pumps, GM said. The problem is likely to affect only a quarter of the transmissions, but the trucks are in such demand that over 8,000 of the 25,000 potentially affected trucks had already been delivered to customers by the time the problem was detected. The 4L80-E is the latest iteration of GM's Turbo-Hydramatic 400, but includes full electronic controls, direct-drive third gear and .75:1 overdrive fourth gear. The suspect 4L80-E transmissions were installed in Chevrolet Express, Chevrolet Silverado, GMC Suburban, GMC Sierra, GMC Savana, GMC Yukon XL and GMC W4 trucks and vans. General Motors said it will not issue a formal recall because it does not believe the overdrive bearing failure represents a safety issue. Instead, the company will attempt to notify all 8,000 vehicle owners by mail and phone calls. They are being instructed to use only first through third gears and avoid overdrive until the transmission can be inspected and serviced.