Torque converter (I think) is making noise

[SUX2BU99]

Soooooo the drama continues from just a bloody routine body bushing replacement. I can't get my shifter adjusted to where I can get Park to work the way it should and have all gears down to First. So anyway, I go to the track a couple weeks ago and before I race it I have this rattle at idle when in gear. It goes away if the revs come up a bit like in Neutral or so.  Hmmmmm, what up? I'm concerned it's the park pawl but it's louder than that. Very metallic sounding. I thought maybe it was my shifter adjustment bolt rattling on my exhaust pipe since I removed a little of the header tape. Nope. Then I think "oh no, maybe it's a rod knock...."  Check oil, it's rather low    Top up oil, say a quick prayer, recrank.......rattle  Craptastic!  Say another quick prayer, ask for the wifes assistance to start it while I crawl under and see where noise is coming from. The rattle was present too as I was cranking it over (before it fired up).

Now I've heard rod knock before and this does sound different. It's quite metallic and not as consistent as rod knock is as the crank swings around. This is little more rattlely than that. Crawl under. Sounds like it's coming from around the back of the pan. DOH! Get right under there and I'm pretty postive it's coming from the torque converter. I was directly under the TC and it was noisy right above me. I checked tranny fluid which seemed okay but the trans wasn't warmed up yet. The noise is only there at idle in gear. Not idle in Park/Neutral.

One thing I have found is that I can wiggle the TC back and forth a little bit. I don't have an inspection cover on the trans (it has never had one as long as I've owned it and I doubt ever has before that) and the attachment bolts to the flexplate, I can rotate the TC a little bit. Maybe an 1/8" or so. Is this normal? When I move it, it makes a bit of a clank as the bolts move back and forth in the hole. I also can see that there is very tight clearance between the rotating TC and the bellhousing. I don't see any paint scrapes though.

I'm not sure why this would happen now. The tranny runs and shifts just fine. It has a shift kit in it and shifts nice and firm. Since the cam was put in, the motor does shake a lot more at idle and especially in park so I guess that could have loosened something. So what does this sound like as the problem?

[Captkaos]

The torque converter shouldn't move independently of the flexplate.  Is it cracked?

[frogman68]

Are the bolts tight ?

[VileZambonie]

Your T/C bolts are loose. Reinstall them with loctite. Also if your linkage is adjusted right and it's popping out of park, drop the pan and make sure the bolts that house the actuator to your park lock pawl are tight.

[SUX2BU99]

Thanks guys. I'll definitely tighten up those bolts first on the TC which hopefully fixes it. I did some reading of other forums and found quite a few instances of the exact same problem (on Mercedes and Ford transmissions). Some were faulty TC's, some were cracked flexplates and a couple were loose bolts. Although, maybe the 'faulty' TC's were really just loose bolts.....

[SUX2BU99]

Well thankfully, this was an easy one! Yep, just the loose bolts were causing the noise. Tightened them up and all is fine. One was very loose, like about to fall out if it wasn't for the nut on it. One was a little more than finger tight and the other was snug but not tight.

[eventhorizon66]

I didn't use loctite on mine either.  Is that something I should go back and do?  Red loctite?  I just had an assistant hold the crank still while I progressively torqued them down to 45 ft/lbs.

[VileZambonie]

When you get bored under there one day go ahead and do so. You should use thread locker.

[eventhorizon66]

Okay, thanks.  I don't know why I didn't think of this before.