That strange noise from your truck’s rear end? It’s easy to ignore until something really lets go. YouTuber Josh from Truck Master got a nasty surprise like that in his ’06 Duramax giveaway truck – a shredded differential – right before the giveaway concluded, making for a very timely video warning for other truck owners.

Josh stated early in the video, “The giveaway truck’s rear end is smoked.” He quickly decided that he should fix it before giving it away. This commitment sent him on a six-plus hour haul to Kodiak Truck / Ryan’s Diesel Service in Wisconsin.

There, expert mechanic Mark inspected the General Motors (GM) Gov-Lock differential and confirmed the damage. “We’ve got a cracked ramp plate … broken in quite a few pieces.”

At Kodiak Truck, Mark wasn’t too shocked by the busted Gov-Lock. “It’s the GM’s claim to fame. I’m not a big fan of it,” Mark commented, adding, “they work as long as you don’t beat the snot out of them too hard.”

The repair involved swapping in a used 90,000-mile Gov-Lock unit from another truck, which Mark set up with a “beautiful” gear pattern. The team also tackled leaking seals in the front differential, with Mark offering a classic piece of shop wisdom: “… fluid’s cheaper than parts so it always will be.”Josh used the video as a teachable moment for his audience. “If you own a pickup truck you need to make sure you check this,” he urged viewers, later warning, “…that could be you guys… not trying to freak you out but it’s possible.”

The repair happened just in the nick of time, as the giveaway for the Duramax wrapped up on May 12. After the fix, Mark noted the truck now “drives straight and everything else and handles nice … accelerates nice,” an assessment Josh echoed after his test drive.

Josh’s trip to Kodiak Truck really showed what can go wrong inside a differential and how pros tackle the fix. It’s a good reminder for truck owners to pay attention to their drivelines. Have you ever run into a surprise differential problem like this one? These kinds of open-book repair videos showing real-world fixes are often a big help to other owners.