This has happened a couple times (~5 times over a couple months). Running 55-60 on cruise with exhaust brake on. I'll get on the brakes and the truck will judder like when you bring a manual to a stop in gear without using the clutch. Truck normally brakes just fine so I'm thinking it's transmission related. I did the trans filter and partial fluid change at 150K when I adjusted the valves. 6.7 Cummins, 68rfe, 4x4, 180K miles (owned since 143K) on it. I don't tow real heavy with it (~8K lbs once or twice a month for 400 miles). I have the Smarty set on the performance tune and have it dialed down to 80% power just for the timing and trans tuning without the smoke. Anyone have any ideas?

 

I'm having sort of the same issue but I have a 6 speed manual tranny. I'm looking at the driveshaft slip joint and the carrier bearing. Does your engine die? If it does, look at the converter. It may not be coming out of lock-up.
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