Truck thumping noise diagnosis

[Irving]

The diff shouldn't thump. If it's getting old, it would need a fluid change and maybe the clutches are wearing. Even if the clutches are worn, it'll just act like an open diff.

[Hummer]

The diff shouldn't thump. If it's getting old, it would need a fluid change and maybe the clutches are wearing. Even if the clutches are worn, it'll just act like an open diff.

Thanks for your comments. I've never had a differential problem in a vehicle. U-joints, carrier bearings, clutches but never killed a transmission or differential. I've raced cars, rebuilt engines and done a wide variety of mechanical work from motorcycles to heavy equipment but now I'm at the station in life that I can let specialists do the high tech or heavy lifting work.

Apparently the Toyota mechanic readily heard knocking in the differential with a stethoscope.

A few other points that were suggested; the tires are new, everything good there. All the fluids were changed in early March. Actually, I suspected the differential and that it might have been drained but not refilled, but no. At the cabin I don't have a garage or a safe lift, only ramps. So, to the shop it went.

For the past several months i've been hauling heavy loads of apple wood from Palisade. It's now more expensive smoking wood and firewood.