Tranny and Torque Converter Questions

[Doctorsmack03]

I have a vibration that I am about 90% sure is a torque converter problem.

Symptoms are as follows:

I HAD an edge chip and took off from a light hard in the highest power setting and felt the torque converter slip and shudder(vibrate) really bad. So I took off the chip and drove it in stock. Now, 20,000 miles later, I have a vibration at 40mph and also at 53mph. Also, the truck somewhat vibrates more than normal while in drive sitting at a red light, but sometimes it is more noticable than other times.

My 1st question is does anyone agree that the torque converter might be the problem?

2nd question is is there anyway to test, verify that it is the torque converter?

3rd question is can I just replace the torque converter and all fluids, filters or is a tranny overhaul required when the torque converter is replaced? My truck has 30,000 miles on it and the tranny exhibits no other failure signs. Tranny temp is always around 140 degrees.

4th question is if I replace the torque converter now and blow the tranny in 10,000 miles or so, is the torque converter trash?

As usual, thank you for the help-this site has saved me many times.

[GregH]

The torque convertor on this truck is very robust. I doubt that it is causing the problem. I would first suspect a driveline angle issue.

Verification of torque convertor failure that causes a vibration would require the use of a vibration analyzer and a scan tool capable of active commands. Get the truck to vibrating - at 40 or 53, then lock and unlock the torque convertor. Watch the vibration analyzer, and see if you've got a 1st order vibration at engine RPM that goes away with torque convertor lock. If so, then the TC may be at fault.

Transmission overhaul is not required with torque convertor replacement.

And, finally, if the transmission fails 10K after TC replacement, then the TC can be flushed and reused - as long as you get all the contamination out.

[Doctorsmack03]

As usual Greg, thanks for the assistance.

As far as drive line angle goes, I bought a CV Driveshaft for the rear as soon as it was lifted. I then had a set of blocks machined for the rear that pitch the driveshaft straight up to the tranny. After all that I thought it was the driveshaft also so I lowered the transmission crossmember an inch and it had no effect. So i took it to a driveline specialist and we test drove it and he said that he would need to keep it for a day to figure it out, but that it definitely wasn't the driveshaft.

Also, the truck vibrates at a red light some times so that is how I came to this conclusion. If it starts to vibrate, all I have to do is tap the gas and the vibration goes completely away.

For example at 53mph if I hold that speed and tap the brake with my left foot, the vibration goes away and the rpm raises to 2100. So I assume that is the torque converter unlocking correct?

Thanks again Greg

[Doctorsmack03]

Has anyone ever done a torque converter on one of these trucks?

[GregH]

Yeah, about a hundred. I was the only tech at my dealer who did the 04B24 recall for the low/reverse planetary assembly. There's nothing to it. Takes about 20 minutes to drop the tranny...

[Doctorsmack03]

Awesome, thanks Greg!