A guy I work with has an 01 6speed cummins. He said every once in a while he will be in 6th gear and no power even if he floors it the rpm stays the same and does not accelerate at all. He can push the clutch and it revs fine, let the clutch out and still nothing... Drop it in 5th and it'll go like hell like nothing's wrong. Back into 6th and its fine for a while. Anyone ever run into this sort of issue? Thanks folks!

 

Usually when they totally fail they will lock in gear usually 6th. Apparently they came from the factory over a quart low on fluid.

My guess would be a bearing starting to seize up.

 

He's had the truck a few years and it's only happened a few times I guess. It's got him concerned an me wondering

 

I've only had my 01 HO for a week and kind of disappointed with the nv5600 transmission.

Upshifts/downshifts fine in all gears and reverse EXCEPT for 6th.

If I double clutch 6th sometimes it goes in no grind other times a slight grind and then sometimes like you hit a wall noway its going in, have to go back to 5th and try again.

Tried shifting from 5 to 6 with no clutch and surprisingly the 1st time it went it with no issues. Next time same crap as with using the clutch.

I had a 12v with the nv4500 and had no complaints with it. I thought the 6 speed was suppose to be an upgrade. Should have done my homework.
Apparently even wehen new they always were notchy and finiky to shift.

 

Hmmm. He said he was on the interstate on cruise control, saw a car coming up and tapped the brake to disable the cruise without hitting the clutch or leaving 6th. Went to throttle back in and nothing.... I guess it's happened a few times.

 

If it only happens after disabling cruise i wounder if it isn't something related to cruise control.
I noticed on mine when you hit the break/clutch it disables the speed control but the cruise light stays on in the dash until you actually hit the off button. Has he tried turning the cruise off then accelerating ?

 

Not sure. I'll ask him when I see him in the morning. We work different shifts.

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Asked him and he said its even happened while not using cruise. He's wondering if the truck sitting for a couple weeks at a time between uses has anything to do with it... He just hauled 10bails of hay at roughly 800lbs a piece the other day n no problems at all... Weird