This is a continuation of my recent thread https://www.dieseltruckresource.com/...d.php?t=214526 about a real bad clatter coming from the tranny area on motor shutdown, and while in gear. Took it to the dealer and got the infamous "can not duplicate" which just happens to be true this time because I just went by to check on things and sure enough, I started the truck (no clatter), ran it through the gears (no clatter), and even on shut down which was when it was the worst (still no clatter).

So, what would cause severe shrapnel like grinding/clatter/shutter to come from the trans. for just a couple of days, then disappear? What are the symptoms of a damaged flex plate? Wouldn't I feel or hear something while driving? How do you check for a damaged flex plate (I assume a full fluid drain and fill is in order)? Can I do more damage to other parts driving around with a grenaded flex plate? I've read of others driving around for too long without getting one fixed.

Or, what else could it be in the trans. that would cause the same symptoms and sounds? Where else should I look? I'm a little paranoid about driving around with something that left unattended could cause a lot more serious damage and ultimately a lot more $.

 

To really check it right you have to pull the tranny. The flex plate is what the torque convertor bolts to. It take the place of the flywheel in a stick shift setup.

 

There were a few threads a while back about clattering/grinding noise mainly when in N or P. Once in D, there was enough load on the loose bolts to stop the noise.

You could crawl under the truck and remove the inspection cover, and see what you can see. In the past thread it was just the bolts. If the flex plate was actually broken or cracked, though, I'd guess you would have to pull the transmission to see it.

 

Remove the inspection cover, you will be able to see the flexpate teeth, place a large screwdriver in there and move the flexplate back and forth, if it is loose you will feel it clunk back and forth. You may even be able to move is side to side as well... since your tranny is stock, I hardly believe that it is loose. The factory puts some pretty good lock tite in there.....

 

^^^^^^^ What he say - sounds like loose bolts or cracked flexplate, and is pretty easy to check.

 

Haven't had to ever check the tranny before, so I'm not sure where the inspection plate is. Is there more than one inspection plate? Is it above fluid level so I don't have to drain it? Thanks for the replies.

 

Remove the 3 5/16" hex bolts from the inspection cover on the bottom of the tranny bellhousing, right behind the engine.

Hopefully, there isn't any fluid in there - but it's probably already drained out on the ground, since it's a dry cover.

 

When you say "dry cover" do you mean it's supposed to be dry, and there's not any fluid cooling the flex plate? I know oil is inside the TC but if there is fluid coming out of the inspection plate is that a bad sign, or just excess spillage of some kind coming from the tranny? I just want to know what I should be looking for and expecting when I crack it open.

thanks for the help

 

The area should be dry but the transmission front seal or crank rear seal can weep a bit. Damp would be considered typical but lots of oil would be a bad sign.

 

Just crawl under and remove the cover. Most likely there could be a few drops of oil from seepage of the engine's rear main, or a bit of seepage of atf from the transmission, but it should be about as dry in there as it would be if you had a stick shift and were looking at the pressure plate and flywheel, as opposed to the flex plate and torque converter on your auto...

 

If you don't want to pull it off yourself, you could always go back to the dealer and see if you can have one of the mechanics come out so you can show him the noise...

 

Ok, that was easy. Just pulled the inspection plate and found the flex plate (w/the teeth). Put a small pry bar to it and worked it side to side and then rotated it each direction. Seemed completely solid with no play in either direction. Not much seepage from the tranny at all.

As I said earlier, the sound hasn't been there for the past couple of days. I checked everything I could see and get my hands on to see if anything was loose or could rattle like that; shields, drive shaft, exhaust hangers, bolts, etc. I guess I'll just drive it like normal and see how it does. Thanks for everyones help and input.

GUS