Grinds Going into Fourth
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Grinds Going into Fourth
Only had my 69 F100 going for a little while now, the original four speed shifted flawlessly at first, but yesterday I took it for a test drive. The transmission was normal, till it was time to go into fourth, it grinds quite loudly now going into fourth. It down shifts fine, and the other gears seem normal. Any ideas?
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Joined: Sep 2009
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From: Burbank, CA
Fourth gear is the "straight through" gear, which means that the input shaft gets coupled directly to the output shaft by a synchronizer ring. Meanwhile, the cluster gear (which is the one-piece group of gears on a secondary shaft) is getting spun by the input shaft, but isn't coupled to anything else.
If you're getting grinding going into fourth only, it usually means that something is dragging down the speed of the input shaft during that second while the clutch is in and you're right between 3rd and 4th. It could be a dragging bearing in the cluster shaft.
You can try changing the oil in the transmission. It could be that the oil is too old and thick. There's also a small chance that the linkage rod that does the 3rd & 4th gears may be a little out of adjustment. It's worth checking. Other than that, you've got to pull the transmission out and apart. Unfortunately, with manual transmissions, it's often cheaper to buy another transmission than it is to repair one.
If you're getting grinding going into fourth only, it usually means that something is dragging down the speed of the input shaft during that second while the clutch is in and you're right between 3rd and 4th. It could be a dragging bearing in the cluster shaft.
You can try changing the oil in the transmission. It could be that the oil is too old and thick. There's also a small chance that the linkage rod that does the 3rd & 4th gears may be a little out of adjustment. It's worth checking. Other than that, you've got to pull the transmission out and apart. Unfortunately, with manual transmissions, it's often cheaper to buy another transmission than it is to repair one.
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Thank you for that info, hopefully the oil will do the trick.
Like I said one day it's fine, the next day it's grinding.
There is something binding in the four wheel drive system. The four wheel drive will not disengage after using it, but that should not have any affect on this transmission problem should it?
Is it really costly to have repairs done to the NP435's?
Like I said one day it's fine, the next day it's grinding.
There is something binding in the four wheel drive system. The four wheel drive will not disengage after using it, but that should not have any affect on this transmission problem should it?
Is it really costly to have repairs done to the NP435's?
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Just want you to learn what I learned so far.
Drained out about 1/2 quart of thick gear oil. Parked it on a side hill so I could get it extra full, and added a quart of A.T.F. Drove it about 15 miles, and it dont grind going into fourth anymore.
Think I should just run it as is?
Drained out about 1/2 quart of thick gear oil. Parked it on a side hill so I could get it extra full, and added a quart of A.T.F. Drove it about 15 miles, and it dont grind going into fourth anymore.
Think I should just run it as is?
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Joined: Aug 2003
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From: **** hole San Jose ca.
Like 81 f150 said 50Wt. motor is what ford says to use in tranny & TF case. The 50wt.
is what the glove box manual says to use. This is now harder to find 50wt. I'm using 60wt. penns racing oil in T case..works for me..my 2cent
orich
is what the glove box manual says to use. This is now harder to find 50wt. I'm using 60wt. penns racing oil in T case..works for me..my 2cent
orich
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