Automatic Transmission Cooler problems of the 2006 GMC Sierra 2500

Went to GMC dealer because truck has a transmission oil leak. Technician noted that all three transmission oil cooler line are leaking. . Read more...

I have a 2006 GMC sierra that has had transmission lines replaced and that keep having to be replaced because of hose leaking every year.

Transmission cooler line leaking transmission fluid at an aluminum crimp that connects a rubber hose to the transmission cooler; an inferior design. As such, a transmission oil leak is a fire hazard. I am aware of two car fires that were caused by leaking transmission cooler lines. The last one involved a Ford taurus station wagon where the owner had the transmission rebuilt by his local transmission shop (a national franchise transmission repair shop) and they cross-threaded the lower cooler line at the transmission. The transmission fluid leaked on to the exhaust cross-over pipe and the car burned to the ground on the side of road in the interstate. The owner's insurance company subrogated against the transmission shop for the damages. Fortunately, no one got hurt, but they came close.

I have a 2006 GMC 2500hd that has 31000 miles on it. The transmission cool er lines are leaking and the dealer has been notified about this problem. The new parts are on backorder, meanwhile the truck leaks transmission oil on the ground which could be a potential fire hazard alone with an environmental hazard. Many GMC 2500hd owners are having this problem. This is not yet a recall but needs to be addressed.