I've got something slipping in the drivetrain. There's a couple of steep mountain passes I frequent, 10%+ grade, traveling 25 - 40 mph, I'll experience a subtle "pop" then a power loss that correlates with increasing RPMs. The experience is very much like driving a standard trans with a worn clutch that's starting to slip.
If I let off the throttle and slow the truck way down it will stop until I bring it up to speed again. Or, if I let off the throttle and press the CDL button it goes away, no slipping. I've gotten to the point that, if I take that road, I lock the center diff before I even attempt it, and the problem doesn't occur.
It's kind of intermittent and illusive. I haven't got all the variables nailed down. I think it usually occurs in 3rd gear, and if I drop in down into second it goes away too, or doesn't occur as often maybe.
I haven't torn anything down, but I've thrown it on a lift and gave it a quick look over. I'm running AVM hubs that seem healthy. No metal shavings around the slip yokes. No metal or anything odd about TC, trans, diff fluids.
So if it's not coincidence that the problem goes away if I press the CDL switch I figure it's got to be something with splines past the center diff, e.g., front hubs, both ends of the front axles, inner ends of the rear axles, pinion flanges, slip yokes, TC driveshaft output flanges.
Anything possibilities I'm missing? What's the most common failure point? In an effort to save time/sanity, what should I check first?
I've thought about trying to gather more data on the problem by, instead of pressing the CDL button, locking the ARBs one at a time to try to eliminate possibilities at least down to inner axle splines, but that sounds sketchy on a winding mountain road. Not trying to die.
If I let off the throttle and slow the truck way down it will stop until I bring it up to speed again. Or, if I let off the throttle and press the CDL button it goes away, no slipping. I've gotten to the point that, if I take that road, I lock the center diff before I even attempt it, and the problem doesn't occur.
It's kind of intermittent and illusive. I haven't got all the variables nailed down. I think it usually occurs in 3rd gear, and if I drop in down into second it goes away too, or doesn't occur as often maybe.
I haven't torn anything down, but I've thrown it on a lift and gave it a quick look over. I'm running AVM hubs that seem healthy. No metal shavings around the slip yokes. No metal or anything odd about TC, trans, diff fluids.
So if it's not coincidence that the problem goes away if I press the CDL switch I figure it's got to be something with splines past the center diff, e.g., front hubs, both ends of the front axles, inner ends of the rear axles, pinion flanges, slip yokes, TC driveshaft output flanges.
Anything possibilities I'm missing? What's the most common failure point? In an effort to save time/sanity, what should I check first?
I've thought about trying to gather more data on the problem by, instead of pressing the CDL button, locking the ARBs one at a time to try to eliminate possibilities at least down to inner axle splines, but that sounds sketchy on a winding mountain road. Not trying to die.
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