Been having a little quirk get worse and worse and now it's a problem! Started off as a freak occurrence, now it does it all the time, no matter what the load or uphill grade:

It usually happens at cruising speeds (about 60 - 80 mph). When I give it more gas, as though to pass someone, and the converter unlocks (it doesn't go down into 3rd yet, it just slightly raises rpms), the truck clunks and chatters repeatedly and shudders REALLY bad, as though it can't engage into gear. Sometimes it just lags until it clunks into gear, but other times it does this shuddering thing. The other day going up a steep grade with my dirt bike in the back, it shuddered so bad the Check Engine light came on and flashed for a few seconds, then turned off. It seems to do this until it eventually engages or I completely let off the gas. Then it runs fine again.
[Edit: A couple times, during the worst shudders, I've heard metallic clanking. Not cool!]

If I floor it and it kicks out of overdrive into 3rd gear, its usually fine. This kind of sounds like a torque converter to me, but I'm no mechanic.

Just serviced the tranny and even added some Lucas junk to it. No metallic shavings in the oil or on the oil pan bolt. So tranny itself might be ok. Plus, the oil change and Lucas additive didn't help a bit.

I'm stumped. Any thoughts????? <img src="/forums/images/graemlins/scared.gif" alt="" />

Have you done the valvebody mod?

The torque converter is shot; any codes to go with it? I see a torque converter change in your future............

No valve body mod. Just checked my tranny fluid, which I only changed about 4000 miles ago, if that, and I could swear it smelled burnt.

Today, it did the chattering thing while shifting into 2nd as well. Sometimes it wraps like the rear end is going to fall off, other times, it just loses power and hesitates while trying to shift down. Sucks.

No codes being thrown. Like I said, the MIL came on and flashed during one of the bad shifts, but as of right now, no codes are stored in the ECU.

It sounds to me like the torque converter can't manage the power anymore and is causing this, but I really don't know what they do when they start failing.

If you say it's toast, then what do you know of as far as signs that a TC is taking a dive?

The chatter that you described is the lockout slipping in and out in the TC. It will get worse in time and chatter so bad you'll swear the dash is going to fall out. I'd get it in and checked out to be sure it's not a bad shift silonoid, but my money's on the TC it's self. There is a good chance you can get by with just a new TC since it has just started messing up on ya.

Thanks a lot for your thoughts. I'll definitely take it in right away. I'm glad there's at least a possibility of it being something not-as-serious as the tranny! <img src="/forums/images/graemlins/shiner.gif" alt="" />

You're right, if I can get away with just replacing the TC, I'd be a happy camper. But with my luck, it'll turn into a $3000 overhaul! <img src="/forums/images/graemlins/scared.gif" alt="" />

Best to prob go with Level 10 or IPT and get a performance torque converter, might as well do the VB mod while you're at it....

You know, it's funny. I was just gonna log on and ask if there was something higher performance I could put on.
Whenever I have to replace something, it feels good putting something a little better in.

What exactly is the valve body mod?
And what do the Level 10 and IPT TCs offer to make them worth the cost? Is it worth it to search one of those out?

By the way, thank you for all your responses so far, it's been helping lead me in the right direction! <img src="/forums/images/graemlins/kewl.gif" alt="" />

This http://www.gadgetonline.com/Transmission.htm should answer all your questions.
And here's a vid of how fast is shifts with the VB mod...
http://www.gadgetonline.com/mvc-001v.mpg

haha Gadget is the best! Thanks for the links, now everything makes a lot more sense. And that video is awesome! I wish my truck shifted like that! Damn!
I'm going to try to take the truck in next week to get fixed, so I'll report back with good or bad news (but let's hope for some good news).
If I can afford it, the Level 10 TC sounds like a bangin' deal. But we'll have to see what the extent of my damage is so far.....
Thanks again for the wise words, Greg.