4-speed experts needed
Thread Starter
Racer
Joined: Feb 2007
Posts: 337
Likes: 1
From: Clyde Ohio
4-speed experts needed
I have a 4-speed that is vibrating in 1-3 but not in 4th. It's more in 2-3. The tranny was rebuilt with all new bearings but I can't recall if I replaced the front bearing on the main shaft. The gears are all good, new syncros, the shafts weren't worn. The tailshaft had a new bushing installed, new crank pilot bushing. If you pick the tranny up by the front shaft and tail housing, there is some movement in the front shaft. I don't know if this is o.k. or not and also besides the vibration it is pretty noisy in those gears. I've put maybe 50-100 miles since rebuilt. I thought I'ld ask for some ideas before I rip it all apart. Could it be the front shaft bearing vibrating 1-3 but not 4?
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
I have a 4-speed that is vibrating in 1-3 but not in 4th. It's more in 2-3. The tranny was rebuilt with all new bearings but I can't recall if I replaced the front bearing on the main shaft. The gears are all good, new syncros, the shafts weren't worn. The tailshaft had a new bushing installed, new crank pilot bushing. If you pick the tranny up by the front shaft and tail housing, there is some movement in the front shaft. I don't know if this is o.k. or not and also besides the vibration it is pretty noisy in those gears. I've put maybe 50-100 miles since rebuilt. I thought I'ld ask for some ideas before I rip it all apart. Could it be the front shaft bearing vibrating 1-3 but not 4?
Burning Brakes
Joined: Aug 2004
Posts: 971
Likes: 7
From: roanoke va
Does shifting hard or NICE and soft end with the same result?
I had a chevyII that was doing about the same thing and the pilot bearing was wore out. When you shifted it hard the input shaft would be mis-aligned and viberated like crazy. When you paused between shifts and give the clutch disk time to center itself the vibration went away.
I had a chevyII that was doing about the same thing and the pilot bearing was wore out. When you shifted it hard the input shaft would be mis-aligned and viberated like crazy. When you paused between shifts and give the clutch disk time to center itself the vibration went away.
Thread Starter
Racer
Joined: Feb 2007
Posts: 337
Likes: 1
From: Clyde Ohio
No. Drive it like your grandma or beat the pi** out of it, no difference. The pilot bushing is new and the shaft has a good fit in it.(checked the bushing fit before install). What gets me is the counter shaft is good, the bearing are new and the gears are great. The countershaft is tight in the case. I'm hoping someone will say xxxxx will cause this, before I start quessing on what to start replacing. I will be tearing the tranning completely apart tommorrow and really inspect it.
Thread Starter
Racer
Joined: Feb 2007
Posts: 337
Likes: 1
From: Clyde Ohio
I'm thinking it's in the coutershaft or gears, but not sure where. Has anyone had this happen to them and why ?
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