HighTen

I know there are several write-ups on changing the clutch already (which I read and found very helpful), but my circumstances gave me a different experience that might be entertaining for some. The truck is a mostly-stock 2004 2WD with 196,000 miles and I chose to put in another LUK clutch. I was working out in the driveway, I don’t have air tools, and I’ve never removed a transmission before. If anyone wants to read the adventure part right away, just skip ahead a few paragraphs.

Most of the preparation /disassembly went pretty smoothly. The lowness of the 2WD made more working room necessary. I first put some jack stands under the frame (by the engine) and under the rear axle. Also, as many of you know, there are a lot of tight nuts and bolts on these trucks! A big 3/4” ratchet with a 1/2” adapter really came in handy for breaking things loose.

With the driveshaft out, I noticed a couple of the u joints were bad. I wasn’t able to budge them so a local driveshaft shop replaced all three (with Spicers that I provided) and re-balanced. The fella who did the work took off that big steel “doughnut” that’s normally next to the forward-most u joint. He said he’s seen them come loose and they make the shaft hard to balance. I don’t remember reading anything here like that. Any thoughts?

I did a stupid thing loosening the rear transmission mount. I didn’t realize the nuts on top are welded in place and DO NOT MOVE. I broke a short extension trying to turn these nuts. So, if there are any here as dumb as me, make sure to loosen the bolt head that’s pointing down.

Also on my transmission, there was an exhaust hanger mounted on the side of the bell housing and it wouldn’t allow the transmission slide back. I had to disconnect the downtube from the turbo to get enough room to get this hanger out of the way.

Now for the big adventure part. I got a low lift 800lb transmission jack from harbor freight for this job. It worked okay to remove the transmission. However, when I was getting the transmission back in place, I was turning the side-to-side adjustment **** when the darn jack CAME APART. In 0.0000001 seconds the transmission flopped sideways and pulled the jack right over with it. It came to rest with the front end up against the exhaust pipe, the back end pointing down, and all the oil draining out onto the driveway. On the plus side, because I used a ratcheting tiedown strap to attach the transmission to the jack (thanks for the tip, guys), the case never actually hit the ground.

As you’d guess, this made a lot of extra work. I’m incredibly lucky that my Dad was available and he helped me a great deal from this point on. He’s very creative and knows heavy objects, which was invaluable in working with that giant transmission. Anyway, it was clean up the oil, get the transmission onto a dolly, jack the truck way, way up, roll the trans out from underneath, use an engine hoist to get the trans back onto a new jack, roll the tans back under the truck, lower the truck back down because the jack won’t lift it high enough now…

With all the work done, the results are good. The driveshaft is definitely smoother and better balanced than it was before. Also, the clutch pedal is so much easier to depress than before. I wasn’t expecting this change but I’ll take it.

And finally onto the pics. In my case, it looks like a bad throwout bearing was the cause of the irritating whining sound. I couldn’t turn at all, holding it in my hands. You can see the groove in it and the flat spot it rubbed into the pressure plate. I also took a picture of the dry, rusty pilot bearing.

I don’t have a lot of mechanic experience, so I like to find torque specs when possible. Here’s a list of torques out of the service manual (as well as the socket size needed in each case):
Frame crossmember: 85 ft lb, 18/21mm
trans rear mount: 40 ft lb, 15mm
Driveshaft center mount: 40 ft lb, 15mm
Driveshaft Companion flange: 85 ft lb, 15mm
Slave cylinder nuts: 16 ft lb, 1/2”
Shift tower: 7.5 – 8.3 ft lb, 3/8”
Trans bell housing: 35ft lb, 14mm
Flywheel to crankshaft: 101ft lb, 18mm
Pressure plate: 22 ft lb, 3/8”

Oh, just one more thing. My search for new flywheel mounting bolts was difficult. The ones on this truck were M12 - 1.25 x 32mm long. None of the specialty fastener stores around had any, because they are extra fine thread they said. The only place I could find them was at a Cummins store. The part number for an eight pack is 3901395. They only problem is the bolts came out to $4.74 each!