Clutch hub broken out

[sag2]

2003 truck, all stock power had a new clutch (O'Reilly Auto Parts) installed a few months ago. Maybe a couple thousand miles on it. Truck went 400k on first clutch. The new clutch broke the center hub out of it just inside of the friction material. The hub is not binding on the input shaft. Damping springs all look good. It also was not completely releasing (hard to shift) for the last couple of weeks before it broke. It seems odd that it would break the way it did. He texted me a photo so I can't post it here. Any thoughts?

 

[Tuesdak]

Make sure the dowel pins on the transmission are in place and the holes aren't beat out. If they are messed up, elongated, bent, or missing the clutch becomes a flex plate and damage shows up quick at the hub. The adapter plate can also warp causing a transmission misalignment. Input shaft bearings loose also come to mind. Mine had a high RPM pedal vibration with a missing dowel pin.

A magnetic dial indicator slapped on the flywheel and then spin the engine by hand to check the pin holes for housing distortion works.

Possible just a defective clutch. IMO This isn't a part I would get at O'Reilly Auto Parts. Couple vendors on here that have extreme support for their clutches you won't get there.

Why/How did the last clutch exactly fail?

 

[RustyJC]

Did the customer have the flywheel resurfaced when he replaced the clutch? If so, there's every chance the machine shop didn't pilot the flywheel off the crankshaft mating surface which would result in axial runout at the face of the flywheel - in my case, .050" inch!! As above, this would turn the clutch disc into a flex plate, and the disc would fail from bending fatigue. Luckily, I felt the problem as a first-order vibration at idle and a pulsing in the clutch pedal when I went to pick up the truck, so the shop got to do the clutch install all over again after pulling the flywheel and sending it to a reputable machine shop that knew what they were doing.

Rusty

 

[Joseph Donnelly]

A lot of companies use Chinesium clutch parts. Ask Peter at South Bend how well that works out. The stuff looks like LuK. Another issue occurs when the installer doesn't have the hub perfectly centered and forces the transmission in, or lets the trans "hang" bending the hub.

 

[GCroyle]

Pics would be helpful.

 

[sag2]

OK, sorry no pictures unless I text them to you. But here is almost the rest of the story. Turns out the transmission failed at about 300k. He purchased a used trans, but come to find out the input shaft is 1 1/4 instead of 1 3/8 because the replacement trans was from a 2000'ish truck. So that made it necessary to install a new clutch, pressure plate, and flywheel for the earlier year truck. Apparently the easy fix of just swapping the input shaft is not possible because the internals of the two transmissions are different. So my thought was the 2003 has higher HP and torque and the pre 2003 clutch is not heavy enough. Looking at the material that broke, it looks like a piece of hardened sheet metal about .030 thick. It does not seem near heavy enough to carry 500+ lb/ft of torque.
The other option is get the correct 2003 transmission and reinstall all the correct 2003 clutch, pressure plate, and flywheel. The final option would be to have one of the clutch shops make him a 2003 clutch disk with the 2000'ish 1 1/4 hub, and install the 2003 flywheel and pressure plate.
Something else I noticed, the hub of the broken clutch plate had worn splines, like the disk had been rattling on the input shaft.
This one is sounding more and more like the LA dealer disaster a few months back.
He had to make a trip to Idaho tomorrow for a job, so it got put back together this afternoon with a new flywheel, clutch and pressure plate from O'Reilly because they covered it under warranty. I'm sure in another few weeks or months we will know the rest of the story.

 

[Blu-meanie]

sag2

Use your phone and email the pictures to your email address. Then you can deal with the picture. Or download the picture to your computer with a cable.

 

[GCroyle]

sag2,

Reading the splines is really important. I look for burrs on the sides, widening of the profile and undercutting of the hub at the pilot where it goes thru the drive plate.

Burrs and widening, I'm looking for angular misalignment. Think of a shim or foreign object between engine face and bellhousing face. Input shaft is coming in at an angle. Ugly. This type of misalignment also causes flexing of the lining springs that I believe you are reporting as sheared. Common result is facings as an intact ring, torsion damper as intact assembly just sheared just inside the ID of the facings. If lining springs are sheared and concerned about torque capacity, how do the facings look? Good condition, not burned, overheated etc. Then clutch was not slipping which is the first failure mode of a clutch being overpowered. Also if overpowering is concern, damper stop pins should be inspected for impact, burrs and undercutting from the hub flange.

Undercutting, concentric misalignment. Think missing dowel sleeves. We installed a clutch for AndyMan years ago, one dowel sleeve missing, undercutting observed. Transmission was reman but missing one dowel sleeve put it all off center.

NV5600 and G56 don't allow old school dialing in of the housing like and NV4500 offers.

They need to look at dowel sleeves and holes. Also never let one hang in the disc during stab, can bend disc and start cracks in lining springs. Should not be an issue on a lift with a decent jack. On the floor things can be a bit more challenging. Ugly.

Gary