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Ok dont laugh i know I'm posting a lot here but i want my car to be optimal for some hardcore racing. I have a 6 gear tranny that I'm rebuilding and I'm looking to make it as smooth and precise as possible. I have the metal idlers for it and a full bearing kit and It's packed with silicone grease. The clutch appears to be loose even when It's tightened all the way down. I have balls in a kimborough spur gear and have it mounted on the transmission. When I tightened the nut all the way down, I can still easily spin the spur gear. What am I missing here? I have the transmission set up according to the manual. Any suggestions??

shoot a picture of the diff assembly, sounds like something may not be assembled right.

It appears as if the diff balls are bigger than the spur gear and keeping the metal side holders from clamping the gear down a bit. Am I supposed to be using smaller balls?

you can hold both outdrives and spin the diff gear? it looks assembled pretty well.

yeah i can hold the whole tranny and still spin the gear. looking at the pictures I'm not sure if I was able to show how the balls seem to raise the metal side plates off the gear just enough to not make contact with the gear itself. If that's the case and is normal, then how is the gear supposed to stay in place under even light acceleration? Is my spur gear too thin? It's a kimborough that I just ordered off Amazon awhile ago but I dont have any original spurs to compare it to (they all melted).

The balls ride on the rings. When the gear spins, the balls are the connection between the gear and the transmission. It should not be tight against the gear. So what you have looks right.

When you spin the gear, does the nut and spring spin or stay stationary? I'm thinking your missing a thrust washer from between the 2 top gears.

I do have all the thrust washers in place, but no the spur is the only thing that spins.

The hub that goes on right before the spring and nut.... it has a oval slot that goes onto the shaft. Is it stripped?

I would pull the diff back out and check it in your hand

It is a little loose.

The diff does work as it should, but the spur spins without turning the transmission.

So wait.....the diff does work? As in when you spin the left wheel and hold the spur the right tire spins backwards? But when you try to put the car in the ground and spin the spur it spins freely? Something isn't right. I don't think it can do that.....

Are you using grease on the balls and rings?

Ok no it doesn't do that. If I spin the left wheel, nothing happens to the right wheel or the spur. I'll check the diff tomorrow.

Yeah rule out the diff first. Pull the whole upper shaft out in one piece and I bet you find the issue. Still sounds like a thrust bearing issue but once you have it in your hand it should reveal itself

I'll post a picture or two of It up tomorrow.