Input shaft runout
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Intermediate
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Input shaft runout
In the middle of swapping auto to manual in my 2000 and curious if you can measure runout of the torque tube input shaft with the tube assembled? There is some wobble on it but the bearings are tight and not crunchy in the least. I pulled it apart to check the rubber couplers as it’s a used tube and might as well before I install it. Couplers are brand new however it was HARD to get the shaft out and just as hard to reassemble it. I had to use a 3lb sledge and piece of 2x4 to get it apart and back together with lots and lots of hits. That didn’t seem normal to me at all. Everything looked great inside but again, once assembled I’m getting a bunch of wobble when rotated. Will the pilot hold it straight? Does it even mean anything checking for runout while the tube is assembled? I’ll get a video later if anyone wants to see. Thanks!
Edit: after searching a bunch it looks like that’s not an accurate way to measure runout and kind of pointless. I sort of figured so since the front is supported by one bearing that sits on an O ring. I was a little concerned with how hard it was to get it apart and back together but I’m figuring everything is fine with it.
Edit: after searching a bunch it looks like that’s not an accurate way to measure runout and kind of pointless. I sort of figured so since the front is supported by one bearing that sits on an O ring. I was a little concerned with how hard it was to get it apart and back together but I’m figuring everything is fine with it.
Last edited by boogsawaste; Nov 25, 2024 at 02:27 PM.
Drifting
Joined: Jan 2008
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From: Florida
St. Jude Donor '09
The propeller shaft run-out is measured while the torque tube is disassembled, there is a procedure for it in the FSM. Did you notice if the snubber located mid-way on the propeller shaft is rubbing the inside surface of the torque tube? if so, you have a bent propeller shaft. I'm assuming the wobble you are describing is at the input shaft while rotating it once it is assembled? That would concern me. Did you disassemble the propeller shaft when you had it out? It is a balanced assembly that must be reassembled in the same orientation it came apart to avoid driveline vibration.
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Yes it wobbles once assembled. The snubber in the center did not rub and I made sure I checked that while it was apart. I didn’t disassemble anything beyond taking the shaft from the torque tube but took note that the arrows on the couplers matched the mounting positions as they’re supposed to at least.
If I smack the shaft with my hand I can get it straighter however it almost feels like it’s binding then. Nothing crazy but a slight tighter spot then it spins easily again until it hits that spot. Not sure what to do at this point. There is no play in the bearings on either side.
If I smack the shaft with my hand I can get it straighter however it almost feels like it’s binding then. Nothing crazy but a slight tighter spot then it spins easily again until it hits that spot. Not sure what to do at this point. There is no play in the bearings on either side.
Drifting
Joined: Jan 2008
Posts: 1,722
Likes: 138
From: Florida
St. Jude Donor '09
Yes it wobbles once assembled. The snubber in the center did not rub and I made sure I checked that while it was apart. I didn’t disassemble anything beyond taking the shaft from the torque tube but took note that the arrows on the couplers matched the mounting positions as they’re supposed to at least.
If I smack the shaft with my hand I can get it straighter however it almost feels like it’s binding then. Nothing crazy but a slight tighter spot then it spins easily again until it hits that spot. Not sure what to do at this point. There is no play in the bearings on either side.
If I smack the shaft with my hand I can get it straighter however it almost feels like it’s binding then. Nothing crazy but a slight tighter spot then it spins easily again until it hits that spot. Not sure what to do at this point. There is no play in the bearings on either side.
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Actually it was pretty straight but binding. When I re assembled it it was smooth but wobbly. This is my first torque tube car so I wasn’t 100% on it all. Crap. Start with a new propeller shaft? Whole torque tube? Anyone have one for sale?
Last edited by boogsawaste; Nov 25, 2024 at 06:39 PM.
Race Director
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From: South Western Ontario
The input shaft is supported by a single roller bearing until installed and then the throwout bearing and the roller bearing support both ends of it. I don't see how the runout can be properly measured when removed from the car myself.
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I completely understand that which is why I was questioning it however I was really concerned that when I would flex the shaft straight there was a very noticeable binding and the shaft did not spin well. I pulled off the propeller shaft and marked it where it wobbled the most. I installed it in a different position on the coupler (to see if the coupler wasn’t perfectly flat or if the driveshaft itself was bent), and the “bend” on the propeller shaft stayed in the same place. I don’t have a lathe to check it but I went ahead and ordered a new one from Texas driveline. I already spent more than I wanted on the swap so what’s a couple more bucks 😩
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Le Mans Master
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I completely understand that which is why I was questioning it however I was really concerned that when I would flex the shaft straight there was a very noticeable binding and the shaft did not spin well. I pulled off the propeller shaft and marked it where it wobbled the most. I installed it in a different position on the coupler (to see if the coupler wasn’t perfectly flat or if the driveshaft itself was bent), and the “bend” on the propeller shaft stayed in the same place. I don’t have a lathe to check it but I went ahead and ordered a new one from Texas driveline. I already spent more than I wanted on the swap so what’s a couple more bucks 😩
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Yeah for sure it was bothering me. Having it disassembled now I rigged up a jig to hold it and it is quite bent! So much so that you can actually see it without even spinning. Saves me tons of time from pulling this again. If I would have put it in that way I would have been on one of those 3 day drinking binges myself 😂
Drifting
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From: Florida
St. Jude Donor '09
Yeah for sure it was bothering me. Having it disassembled now I rigged up a jig to hold it and it is quite bent! So much so that you can actually see it without even spinning. Saves me tons of time from pulling this again. If I would have put it in that way I would have been on one of those 3 day drinking binges myself 😂
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I got it as a package from the Facebook marketplace. I don’t think there was any malice at all. The previous owner was going to use it as a manual swap for his however he totaled the corvette before he got to it. Everything he pieced together that was supposed to be brand new was in fact brand new.
Le Mans Master
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Yeah for sure it was bothering me. Having it disassembled now I rigged up a jig to hold it and it is quite bent! So much so that you can actually see it without even spinning. Saves me tons of time from pulling this again. If I would have put it in that way I would have been on one of those 3 day drinking binges myself 😂
Trust me ive been there. If you guess it, change it.
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4th Gear
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Yeah for sure it was bothering me. Having it disassembled now I rigged up a jig to hold it and it is quite bent! So much so that you can actually see it without even spinning. Saves me tons of time from pulling this again. If I would have put it in that way I would have been on one of those 3 day drinking binges myself 😂
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Intermediate
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Sorry for the late reply. For a jig I cut 2 pieces of wood with a V cut into the top of both to hold just the front shaft. That way I could slowly spin it and measure the runout. I ended up installing one of the upgraded ones from Texas drivetrain.
Le Mans Master
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