Three problems related to transfer case have been reported for the 2004 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 GMC Sierra 1500 based on all problems reported for the 2004 Sierra 1500.
Power train pcm defective with transfer case with bad designing with shoe pump, and brake line corroded and leak. Brake system will not prevent vehicle to stop when brake lines are leak. For my 2004 I was lucky driving on slow speed on city road, and I was able to use emergency brake to stop my truck.
The contact owns a 2004 GMC sierra. The contact was towing a boat and discovered there was transfer case oil splattered all over the boat. The vehicle was taken to an independent repair facility where he was informed that there was a hole in the transfer case. A new transfer case and pump housing were installed at the independent repair facility. The failure did not recur. The failure and current mileages were 82,000.
Transfer case nv 246 internal oil pump wears hole in magnesium case and leaks oil completely out of transfer case. Oil coats underside of vehicle including hot exhaust system. Smoke appeared from vehicle. Transfer case made abnormal grinding noise and then overheated damaging internal components. Transfer case requires replacement. Vehicle was completely disabled because of failure. Fire was averted. Vehicle maintained at dealer exclusively except for oil changes. Dealer never provided any info regarding potential major design flaw. Repair quote from dealer $2200.