Trans Metal Shavings - Torque Converter?

[mosel70]

I've got a 1970 Chevy C10, 396 motor, with a TH400. I took it in for its first trans service and found a lot of metal shavings to include two piles of shavings. It shifts fine (has a shift kit) but it vibrates and makes some clunking noises when I decelerate, at idle, and when turning left (not right though). Any chance that might be just the torque converter?

[Gromit]

Some amount of debris is normal; but it is difficult to tell from the photo what you have going there.

By first trans service you mean since you've owned it of course but how many miles has that been?

Can you tell if any of that debris is aluminum? Maybe try to separate it from the metal debris with a magnet; (though the chromium from the bushings won't be magnetic so even when separated it will still be a little uncertain).

I don't know the TH400 at all but I am familiar with the TH350 and they are kinda similar. On the TH350 if you start seeing a lot of aluminum pieces it is best to stop running it in my admittedly amateur opinion.

Because the rebuild kits are cheap but you are less likely to be able to put in a rebuild kit if the aluminum case gets chewed up, so you don't want that.

Here is a pic of a TH350 rebuild kit; you can see these are most of the wear parts besides the pump. It would be common and expected to have some debris from the clutches.

[trac209]

With symptoms like that and the pan evidence id say you have an issue that will most likely result in that trans needing a rebuild soon

[mosel70]

I got the truck this summer, unknown mileage. It originally had a 4 speed manual and a prior owner put in the TH400. Kinda sounds like a new rebuilt with torque converter is needed, huh. Phoenix transmissions has good ones at a reasonable price. I'll try them.

[Gromit]

Whoa, nice truck! And with the 396 and the TH400 holy smokes that must be fun to drive.

Yeah, there is no getting around replacing the whole system (transmission, torque converter, and at the very least flushing the transmission cooler and its lines)..

'Cause you don't wanna get a new trans and then pump a bunch of dirty fluid through it from an old converter and or old lines and/or cooler.

Luckily it is a no brainer with a truck like that it is totally worth the investment.

One other thought: I mentioned that rebuild kit showed most of the wear parts but later I thought of two exceptions - there are the two roller spragues that cost about $20 each and I have no idea why they would not be included in a normal rebuild kit.. they each have about 80 parts - any one of which you can flick out with your fingernail and would ruin a trans if they fell out - so why someone would rebuild one of these and not replace the two spragues is beyond me.

Anyway if you see any chunks in your pan that look like pieces of the the part in the attached photo then definitely don't even start the truck until you R&R that trans.

[mosel70]

I found out my new valve cover on the drivers side was hitting the firewall. I dented in the valve cover corner and truck is completely vibration free. Shifts just fine, so no trans needed for now. Nice ...