dave70

iTrader: (2)

Ok i pulled the trans this morning to change the clutch and hydraulics. LS7,Tick master,speed bleeder,new slave. When i pulled the trans the slave and throw out bearing came apart . Looking at the clutch (stock 100xxx mile)the outer edges were contacting the pressure plate.ate away about 1/16" of material. the input shaft where the pilot bushing rides is ok a little grooved but less than 0.002" the pilot measures 0.590" the pilot bushing is badly worn. I'm calling it a bushing because i dont think it eas a bearing if so both the inner race and the needle bearingd are gone without a trace so i'm assuming it's a bushing and i did have a problem with it going into 3rd an 4th also jumping out of 4th .Question is what do y'all think would cause this? What bearing is behind the input shaft? I was going to tackle the rebuild but am wondering how much this is going to add to the cost. Thanks for any help y'all can give

LS123

iTrader: (11)

Try moving the input shaft and see if you feel there is excessive play on it. The input shaft/main shaft is assembled with a preload (0.003") but over time, the bearings/race wear and cause it to have play. Do you have any other problems with the trans other than 3-4 gear jumping? Do you have any noise issues?

dave70

iTrader: (2)

no no noise at all. i was expecting a bad 3-4 syncro or blocker rings.I just started tearing it down tonite but stopped at the tailshaft housing untill i can take pictures and get some wooden dowels or somthing to place the components on to keep them in order.I found a part of the inner race for the pilot bearing but not one needle bearing.I could move the input shaft a small amount no thrust movement but up and down side to side it would move 1/32" to 1/16" but it may not have been that much it may have just seemed like it.I would post pics of everything but have to figure out how to first lol. Thanks a lot.

LS123

iTrader: (11)

If you have no noise and jumping out of 3-4, it could be broken fork pads/broken synchro keys. Once you remove the main shaft and see the 3-4 synchro, you'll know.

Your pilot bearing should have a roller bearing on the back of the crank. If it's missing all the bearings, you do have other issues.

dave70

iTrader: (2)

yeah it was a bearing i found a part of the inner race but all the needle bearings are gone without a trace. but the end of the shaft that rides on the bearing somehow made it without much damage i fitted the new pilot bearing onto the shaft and it fits fine. guess i got lucky on that one. i need to get it apart and see what it looks like. you said that the bearing on the shaft has a 0.003" preload. What sets this preload? A shim? maybe that is worn guess i won't know till i get it apart i'll post up when i get it apart.....i"m sure i'll need more advice lol

LS123

iTrader: (11)

The shims are place behind the bearing race to "set" the preload. This is from a Vette trans but F body is similar.

dave70

iTrader: (2)

thanks man so the shim simply goes behind the outer race. i think i saw a thread somewhere on checking endplay i'll have to look it up.

dave70

iTrader: (2)

Ok update i have everything apart and the bearings all look fine. No excessive wear on them. The syncros are all worn i'll try to get pics up later. the blocker rings are of course worn and the shift fork pads. everything else looks good. I'm thinking of the tick level 2 kit. it has everything i need except the 5-6 syncro and i might leave that one in there it's not THAT bad and will never try to speed shift 5th or 6th. I'll try to get pics up later. Oh is it posible to have the pilot bearing THAT tore up and NOT damage the imput shaft bearing?

twelver12

iTrader: (3)

usually jumping out of gear is caused by the detent spring/ball on that rail

unless you just mean its jumping out of gear when your letting the clutch out

85MikeTPI

iTrader: (9)

I've never seen a detent fail..

If it jumps out of gear, it means it was never fully in gear.. Fork pads and synchro keys are the number-one causes of that.

dave70

iTrader: (2)

fourth gear is on the input shaft so if the piolt bearing is out the shaft is wobbling around and so is 4th gear so it seems like that could make it pop out under throttle like mine was doing???? i think anyway lol. this is the first one i take down. the detent and spring check ball etc was fine.Also i was thinking last night the input bearing should not get that much use as the input shaft and 4th gear are at a 1 to 1 ratio with the engine. The only time the shaft should spin in the bearing is when the clutch is actualy depressed. Am i right ? My pilot bearing and clutch did have about 118,000 miles on it though and clutch dust prob. took it out at least i hope so.

LS123

iTrader: (11)

It's a good idea to replace all the bearing with over 100K miles even if it looks fine. The bearings are not too expensive and I'm sure you don't want to do this again.

The input shaft (also the 4th gear) turns when you let OFF the clutch, not the other way around. When you let the clutch pedal up, the engine is turning the input shaft. The input shaft/4th gear turns the cluster gear (counter shaft) in neutral.

Here is how you check the main shaft endplay. I made my own tool for the dial indicator to sit on. This is for a Corvette but the Fbody main shaft is shorter.

dave70

iTrader: (2)

Right but what I mean is if the clutch is engaged then the input shaft has to turn the same rpm as the crank so the bearing is doing nothing but keeping the shaft centered ie not spinning. The only time the imput shaft is actually spining in the bearing is when the clutch is depressed and the imput shaft and the crank can spin at a diff. Rpm the bearings may get changed I guess now is the time to do it but I have to see how hard it is going to be to get the old ones off and the new ones on.

LS123

iTrader: (11)

This is incorrect. Anytime the input shaft turns, the bearing turns.

dave70

iTrader: (2)

We are talking about the piolt bearing right? If so I am missing somthing. The input shaft HAS to turn at the same rpm as the crank if the clutch is engaged unless the clutch is sliping ( by engaged I mean the clutch itself not the clutch pedal). And if they are spinning at the same rpm how is the bearing spining? Am I missing somthing ? And thanks for all the help man.

LS123

iTrader: (11)

You stated "input bearing" not pilot bearing. Then you are correct.

dave70

iTrader: (2)

My bad lol . Just wanted to make sure I wasn't missing somthing. Thanks man.