Transmission clanging noise

I'm not an expert with Transmissions and I'm sure someone will come along that knows more than I do but my own opinion is it sounds like maybe your counter shafts are moving.

If it were me and I had enough room, I think I would take the top cover off and inspect the forks and see how the gears look. This may be something that's just starting but I would imagine if the counter shaft(s) are moving around that's going to wear the teeth on your gears because they are coming out of alignment. I would reach down in there and see if you can feel any play in the shafts. If the play is bad enough that you can feel by hand that's a real problem.

Okay that's my two cents let's see what the experts say.

 

@AModelCat
@spsauerland
@BoxCarKidd

If any of those people that I called answer your question they can give you a much more definitive answer than I can.

 

Transmission model number? Happens up shifting between which gears?

 

In my opinion, I would first check engine/ transmission mounts, depending on the make and arrangements. If there is something moving around in the case that shouldn’t be, ie. counter shafts and such, it will eat itself pretty quickly, as that will put the shafts out of time, at minimum. If mounts, u-joints, yokes and such check out visually, I would drain the oil and see what kind of iron is on the plug for starters.

 

Sounds eerily similar to when the power divider went out on me once.

 

One time my truck in certain gears I think it was about two gears I could feel something in the shifter and I began to wonder if my transmission was having a problem.

So I went to buy a new set of tires and the old set had a little bit of River wear because they came off of another truck and I put new tires on it and it completely went away.

So it certainly is possibly could be something behind the transmission I hadn't thought of that.

We don't know what kind of truck you have but if the engine mounts are bad on a Freightliner or any of the regular trucks that don't have a pedal that go through the floor like the peterbilt, your clutch will feel funny.

When you let the clutch out it will feel erratic because what's actually happening is instead of you engaging the drive shaft and it's smoothly turning, the engine is actually lifting before it moves the drive shaft and it's lifting your linkage and everything else.

So in that case you would feel that in the clutch if it wasn't the Peterbilt type that goes through the floor.

 

I would check the u-joints, carrier bearing and the driveshaft(the slip thru part), they usually get missed on being lube.

 

Transmission should have a metal tag on it.