Transfer Case Grinding
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From: Flaherty, KY
Transfer Case Grinding
This may be a dumb question. When sitting at a stoplight , I was messing with the four-wheel-drive selector and noticed that with the clutch out the gears would clash between neutral and four high and low. With the transmission in neutral, presumably the output shaft is stopped; and with the drive wheels stopped, what is there to grind? Or is my understanding of these systems flawed?
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From: Virginia
The tranny has a input shaft that fits over the output shaft with small needle bearings in it. When you are in neutral and let the clutch out, you can hear some whirring because the input shaft and a couple of the gears are turning. And those needle bearings are turning and running against the output shaft. The truck/transfer case is holding the output shaft still.
When you put the transfer case in neutral, you are releasing the output shaft of the tranny, letting it freewheel. So the needle bearing area would rather go ahead and turn the output shaft instead of turning the needle bearings.
I don't know if I explained that very clearly.
When you put the transfer case in neutral, you are releasing the output shaft of the tranny, letting it freewheel. So the needle bearing area would rather go ahead and turn the output shaft instead of turning the needle bearings.
I don't know if I explained that very clearly.
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From: Flaherty, KY
Clear enough, I guess I wasn't aware that the input shaft would turn the output shaft when it's disengaged from the drivetrain.
So when the output shaft is turning in neutral, forcing the transfer case into gear will stop the output shaft (hence the grinding), and then the needle bearings begin to turn as the output shaft comes to a stop.
So when the output shaft is turning in neutral, forcing the transfer case into gear will stop the output shaft (hence the grinding), and then the needle bearings begin to turn as the output shaft comes to a stop.
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From: Virginia
Clear enough, I guess I wasn't aware that the input shaft would turn the output shaft when it's disengaged from the drivetrain.
So when the output shaft is turning in neutral, forcing the transfer case into gear will stop the output shaft (hence the grinding), and then the needle bearings begin to turn as the output shaft comes to a stop.
So when the output shaft is turning in neutral, forcing the transfer case into gear will stop the output shaft (hence the grinding), and then the needle bearings begin to turn as the output shaft comes to a stop.
Power comes in on the left side on the red shaft. The needle bearings are on the intersection of the red shaft and the green shaft. Power through the tranny actually goes down through the lower blue shaft, and then back up to the green shaft on gears 1, 2, and 3 and reverse. All they do in 4th gear is actually lock the red shaft and the green shaft together, so power goes straight through the tranny. That is the only time those little needle bearings do not turn, is in 4th when both shafts are locked together.
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From: Plant city florida
Franklin you are being extra helpful today I have to say. I noticed exactly what the OP is describing last week when I was spinning the Input shaft on my 2 np435 units and the output shaft spun. Is the way to stop this basically use the clutch instead of neutral to shift the t-case? Doesn't it actually say that on the 4x4 sticker on the sun visor?
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