Thread: gear set, 4th gear hub, channel plate gouged! help!

OK so i tore my trans apart today and found one of my thrust washers was trashed between the gear and channel plate, my 4th gear hub was rubbing the chain gear. Both gears have some rash on them from this and the 4th gear hub has rash on it and also the channel plate. Any ideas on what caused this?!?! The chain and gear set was a 7/8th 2.93 ratio.....

channel plate


4th gear hub


drive gear (this is where the bushing was trashed) i removed the retainer clip, it was installed.


driven gear

Edit...I take that back. If that pic was taken how you found everything there is a chance that with the bushing being destroyed on the drive gear that it has cause the driven gear to "walk" toward the driver side of the car causing some issues. Still wouldn't explain the interference between driven sprocket and 4th clutch hub.

As far as the bushing that goes between the drive gear and channel plate I am going to have to stick with installation error. Did you even find remnants of the bushing? was is ever put in the trans? Without it, it's going to cause damage just like you have pictured.

Additional Edit....Where is the drive sprocket retainer clip that holds the sprocket in place on the input shaft?

Hi John...

Drive gear bushing IIRC is plastic. Pat said you guys found pieces of it, so it had been there at some point. If there wasn't enough trans goo on it to hold, it may have gotten mashed upon install. Unless the welds on the reluctor tore it up over time, tough for that to happen if the pin heads don't usually hurt it.


4th hub to gear. Should not be possible with the plastic bushing there. Put them together outside of the trans and see if they hit. I bet they don't. Which means they must have gone in looking like that.

The bushing that goes in between the channel plate and drive gear is known to fall out of place during installation if you're not paying attention. I always use a big goop of petroleum jelly to make sure that the bushing stays oriented and in place during installation. If it was out of place or not seeded properly the bearing would have been destroyed shortly after first start up.

Were the sprockets also purchased from Tim King. Because with the additional information about having the drive sprocket retainer clip in place they only way that I would see that the driven gear would have interference with the 4th clutch hub would be an issue with the specifications for the machining of the sprocket for the 4T65E application.

No comment on Tim King.....other than I will never do business with him.

Your driven gear is not machined properly IMO....Here are a couple pic for reference as to what it should look like. Notice that your spocket has a ridge right in the area where you are having the interferrence issue.

You know Greg, some people label them by teeth. That way when the diff ratio changes..the writing isn't wrong.

Pic was stolen from the internet. Just showing the example of what the driven sprocket machine surface was supposed to look like.

Use the outer set of holes as a reference point. On your ZZP high quality part..that bevel is right at the hole. On the other pic...it's been machined much further back

In between the red lines you'll see that there is an extra ridge that should have been removed during the machining process. Which is exactly where the 4th clutch hub is rubbing on the driven sprocket. Green circles are what you should reference as far as the distance it should have been machined.

Greg..you are informative...

Cause of the bushing to rub on the channel plate is going to be cause by install error IMO. If it falls out of place or is crushed during the install the bushing wont last 10 miles.

Replace the 4th clutc hub. You're talking about a huge turbo build with a 1" GMR chain........why cheap out on a part you get can get new for $35.

I say keep the 4th hub. Nothing ever touches it where you have that "mark" on it. It's not a structural or strength probably from the mark on it. Call it a character mark.

Fine Bill....keep it in there....How do the splines look on the other side of the 4th clutch hub. If there is signs of wear, for sure replace it.