strange rattle from trans area when clutch is out

[97grnrs]

i hear a rattle/bearing noise from the pass trans area, i replaced the throw out bearing last night it still does it. it sounds almost like the same noise when a throw out bearing goes bad, at idle i dont hear it . the engine rpm has to be like 3k or higher to hear it at idle. but if i push clutch in it stops, when im driving i can slightly hear it mosly only on decel. when i accel its quieter, so besides the TOB what could poss make that similar noise and go away when the clutch is pressed in? 95 awd talon tsi

 

[Boostdriven]

Nothing will wall out if you take that synchro out, just don't drive the car or try to shift gears when you do the test. If it turns out that its the synchro that's making the noise then you can bend that wavy ring a little bit. When you have it out lay it on something flat and measure how tall it is to begins with. Use something round like a 10mm socket and bend the ring over it so you don't put sharp bends in it. Bend the rind in places where it touches the cover not the synchro. Try to make it about 1/8" taller then it was before, you don't want to make it much taller then that so it don't put allot of pressure on the synchro causing the ring to wear out prematurely.

The thinner the oil the better the tranny will shift but thinner oil is worse for the bearings and the gears. I bet if you drained the oil out of it and drove the car it would shift like never before but the tranny wouldn't last very long. If you car has some miles on then should baby the tranny under normal daily driving conditions. Never down shift when you're slowing down, its unnecessary, brakes are a lot cheaper to replace then to rebuild the tranny. Synchros wear out much faster on the down shift then the up shift. The way I look at it is when you're going to the store you're not at the race track, so there is no point in driving it like you're at one of course we don't buy these cars to baby them all the time but the more you take care of it the longer it will take care of you.

 

[97grnrs]

well i tried that test. it doesnt make the noise with the synchro out, it does have another noise that goes away when i push the clutch in but its not nearly as loud as that rattle im hearing. i also noticed the 36mm nut was not fully tight on the middle spider gear so i tightened that and re crimped it. im waiting on the fluid to arrive soon and gonna drive it again i hope its fixed but i doubt it, if it still makes the noise after this im gonna just drive it till something goes bad , if it ever does, i did find a spare trans for 500$ so guess ill have to pick it up next week in case , the nut actually wasnt loose it was crimped down but it was not fully tight. i was able to push and pull the middle gear in and out a bit so i tightened it down and now it has no movement.

 

[Boostdriven]

Yeah that lose nut on the middle shaft was not helping you either, hopefully bending that ring a little bit and tightening that nut helps out with the noise. Good luck man.

 

[97grnrs]

well it still makes it so i have no idea. if it was a bad bearing or something i should see metal in the oil but i dont. its def coming from the area of that synchro though., just bought a used trans , supposedly good condition. ill be putting it on tomoro

 

[97grnrs]

ok so i put the used trans in today. its ok but if i dont hold the clutch in for about 5 sec before i shift to 1st it will grind. and i have to shift above 3-4k rpms in second and third or it will grind which makes me think the synchros have seen better days,. so i took my rattling trans apart and every bearing spins free and has no signs of wear, they all have a bit of movement to them but once they are seated in the races they spin normal. now . i did find that the bottom of one of the main gear shafts is rubbing into the trans body itself a little. in the pic u can see where the signs of rubbing are. what would cause this and how would i fix it? if i can fix this i may have a good working trans again. this is all i can find that might be causing that noise. and i wanna do a 3rd and 4th gear synchro too cause it was always notchy in those gears. could an over tightened 36mm top nut cause that to dig into the trans like this or something else?

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, another thing i found which might be normal is when i rotate this center diff piece if i push down on it and spin it it feels very rough, if i pull up on it and spin it its free, is that normal?

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[Boostdriven]

Yes that's normal. Since you have the center diff out you should take it apart and inspect the 3 metal shims that are in it. 2 of them sit behind the spider gears and one sits behind that gear that you were spinning. That shim gets a lot of abuse and if it wears out and breaks it can take out teeth on the gears like no other.

 

[97grnrs]

im gonna do just the intermediate gear bearings in this trans and re assemble. should stop the noise and be a good trans again

 

[Boostdriven]

Trust me you won't regret taking that center diff apart. Those shims are nothing but metal and they do wear out. They will not cost you more then $30 dollars but its the best $30 dollars you will spend. There is nothing to it just make sure you put a little bit of red lock tight on those 8 bolts in the center diff. I've taken several teannys apart where everything looked good but those shims were on the verge of breaking. It's a cheap insurance for a longer tranny life.

 

[97grnrs]

ok ill check it out. would you have any idea why a trans would feel real notchy when its cold out then shift like butter when its warm? the new one i put in for now does that. if i dont either double clutch or rev the engine up to about 4k or better it will shift 2nd and 3rd rough,, if i double clutch it goes right in or if i keep the rev higher it goes right in but if i just do a normal shift at lower rpm it will feel real rough , ive tried synchromesh and royal purple 7590 , feels the same with both. but after about 15 min of driving it shifts smooth as butter at any rpm?? i also did the idle synchro test by pushing it toward all gears without clutch. gently. the motor rpms will die down like normal and no grind when i try that in any gear?? is this just normal. my other trans didnt do that