Two problems related to engine cooling system have been reported for the 2005 GMC Sierra. The most recently reported issues are listed below.
Since we purchased the 2005 GMC Sierra we have had problems with the radiator hose bursting within the first few months and having to have it towed. Since then we have had several overheating problems. The dealer constantly says they can not find anything wrong. We insisted they change the thermostat on one of our times there = they replaced that and a hose. We came home and anti-freeze was leaking. We thought it may be they overfilled it. Then it kept leaking and the truck overheated again 4th or 5th time. This was just driving home from about 10 miles. We had it towed in again and again were told they can find nothing wrong!!! we want answers to this problem. This truck is used for our business and in a year have had to have a new vehicle towed in 3-4 times and driven in. We want answers. We suggested they change the water pump after talking to another mechanic and they said they had problems with that in a different year truck, but have since fixed it. So instead they send you home and do nothing.
Extreme overheating of 3500 duramax while towing. Loss of power and overheating of transmission and engine. Numerous contacts with general motors and attorney general in michigan. Gm acknowledges there is a problem but don't know what the problem is therefore no fix for the problem. Are continuing to find a fix. We tow a 5th wheel in the colo. Mountains and this could lead to very serious problems if the engine should blow and we would have loss of steering and braking.