9-inch guys -- How deep should the driveshaft sit in the transmission tailshaft?
06-01-2009, 08:15 PM
#1
Launching!
Thread Starter
iTrader: (2)
Join Date: Jan 2003
Location: Downtown Chicago
Posts: 265
Likes: 0
Received 0 Likes
on
0 Posts
9-inch guys -- How deep should the driveshaft sit in the transmission tailshaft? I've got a crazy vibration in my driveline starting between 60-65 mph, and I've finally got some time to get the car on jackstands and diagnose it. Based on some of the searches I've done, I suspect that it's due to the driveshaft being too short (like in this thread).
Is there any rule of thumb about how many inches the yoke should stick into the tailshaft? I've got an LT1 T56, if it matters.
Thanks
Is there any rule of thumb about how many inches the yoke should stick into the tailshaft? I've got an LT1 T56, if it matters.
Thanks
06-02-2009, 09:37 PM
#3
Launching!
Thread Starter
iTrader: (2)
Join Date: Jan 2003
Location: Downtown Chicago
Posts: 265
Likes: 0
Received 0 Likes
on
0 Posts
I'm using a 3.5" steel driveshaft made at a local speed shop. I took the original measurements for the shaft, and I think that was my first mistake 
The part number on the yoke is Spicer C 3-3-649-2. I haven't been able to find any official measurements on it from the Dana website... but it is noticeably shorter than the yoke that I had on my last driveshaft.
Here are the measurements:
Centerline distance between U-joints: 41"
Length of "nose" on yoke: 4"
Overall length of yoke from u-joint centerline to tip: 6.25"
How deep should it be engaged into the transmission? Is there any chance that I can just swap to a different yoke and be OK?
EDIT -- this guy has the same yoke, but I think my driveshaft is too short for it.
The part number on the yoke is Spicer C 3-3-649-2. I haven't been able to find any official measurements on it from the Dana website... but it is noticeably shorter than the yoke that I had on my last driveshaft.
Here are the measurements:
Centerline distance between U-joints: 41"
Length of "nose" on yoke: 4"
Overall length of yoke from u-joint centerline to tip: 6.25"
How deep should it be engaged into the transmission? Is there any chance that I can just swap to a different yoke and be OK?
EDIT -- this guy has the same yoke, but I think my driveshaft is too short for it.
Last edited by trax; 06-02-2009 at 09:44 PM.
06-07-2009, 10:45 PM
#4
Launching!
Thread Starter
iTrader: (2)
Join Date: Jan 2003
Location: Downtown Chicago
Posts: 265
Likes: 0
Received 0 Likes
on
0 Posts
Update:
I re-measured my setup for a driveshaft, and it came out to 45" by the yoke-to-tailshaft measurement. It looks like the current one was roughly and inch and change too short. I replaced it with a 4" aluminum one. The driveshaft shop that did it specializes in both heavy-duty industrial shafts as well as drag cars, and they said I should have NO problems taking a stock-weight car into the low 10s with that setup.
Installed the driveshaft last night, set pinion angle, and driveshaft vibration is SIGNIFICANTLY reduced. I suspect that any remaining vibration is an artifact of my LG rod-ended coilovers and my rod-ended LCA's.
I'll keep you guys posted as I find out more...
I re-measured my setup for a driveshaft, and it came out to 45" by the yoke-to-tailshaft measurement. It looks like the current one was roughly and inch and change too short. I replaced it with a 4" aluminum one. The driveshaft shop that did it specializes in both heavy-duty industrial shafts as well as drag cars, and they said I should have NO problems taking a stock-weight car into the low 10s with that setup.
Installed the driveshaft last night, set pinion angle, and driveshaft vibration is SIGNIFICANTLY reduced. I suspect that any remaining vibration is an artifact of my LG rod-ended coilovers and my rod-ended LCA's.
I'll keep you guys posted as I find out more...
