Engine/Transmission (1998.5 - 2002) NV5600 dropped 4th gear

[IndyBoy]

Last night, I was driving home with no load and was accelerating after a corner in 4th gear under a medium/average acceleration and without warning, there was a loud bang, like a firecracker went off under the floor boards. 4th was instantly gone.

All other gears were fine but when I put it in 4th, it acts like neutral, only I can hear a slight decelerating whine when I'm in 4th and then push the clutch in (for half a second). It feels like it shifts into gear, but there is absolutely nothing there. When its in 4th, if I let the clutch out, there are not any notable noises. In neutral with the clutch out, there seems to be a little more noise from the trans in general.



I was running 6 quarts of Amsoil Synchromesh. And there are less then 2000 miles on a new 4th countershaft gear and syncro. (along with 5th, 6th and reverse).



Any Thoughts?



I'm going to take the accessory panel or shifter off this Friday to look inside and see what I’m dealing with. But I’m not looking forward to fixing this thing again.



Has anyone ever downgraded to the 4500 or is that a bad idea?



Derek

 

[IndyBoy]

I work out of state, so I'm itching to be able to look in there and see what the problem was. But all I can think of, is either the sliding 3/4 shifter lost all its teeth instantly on the 4th gear side (3rd still works great). Or the portion of 4th gear that goes inside the sliding shifting mechanism sheared off (this sounds like crazy talk).