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Do I need to shim the pivot ball/grind fork?

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4gfun

Supporting VIP
2,009
55
Dec 10, 2007
Ask Me, Virginia
I am putting in a new XTD Stage 4 Flywheel, Pressure Plate, and Clutch.

The tranny is off the car. The fork and pivot ball look fine to me. I was wondering if I need to shim the pivot ball or grind the clutch fork. They are unshimmed as it sits.

I know where the end of the fork where it meets the slave needs to be but do I have to bolt up the tranny just to find out where it sits?

Thanks
 
Thank you, failed to mention one thing. The tranny is a Noyan rebuilt unit...probably rebuilt about 36k ago not sure if the pivot ball and fork were replaced during that rebuild since I didn't own the car when it was rebuilt.

Isn't the slave cylinder rod a bandaid? That is what lots of folks here have said in the past.

I never had any issues running one on my previous DSM so not so sure why it is considered a band aid.

Thoughts?

You shouldn't if all is working as it should. If needed you could also get the extended slave rod once its back together
 
Personally, Id buy new fork and ball, since shimming is really only a bandaid for a worn ball and fork, and, its almost impossible to visually distinguish a worn ball and or fork from a good one. The ONLY real way to determine if theyre worn, is when the trans is ON the engine WITH the new clutch and flywheel installed. You have to look at where the fork comes out of the tranny, and push the fork toward the passenger side so it puts the throwout bearing against the fingers of the pressure plate. (You will feel the fork stop against the fingers and it doesnt take much force) Now, look at the end of the fork. Is it angled more toward the PASSENGER side, or DRIVER side of the car??? A good fork and ball will leave the end of the fork angled toward the driver side; a worn setup will be opposite, or dead in the middle. If you dont want to buy a new fork and ball, shim the old ball and be done with it. Also, be sure that the flywheel step height is correct for the clutch you are using. Do this, or you will have to pull the tranny out again and it sucks, trust me

Thank you, failed to mention one thing. The tranny is a Noyan rebuilt unit...probably rebuilt about 36k ago not sure if the pivot ball and fork were replaced during that rebuild since I didn't own the car when it was rebuilt.

Isn't the slave cylinder rod a bandaid? That is what lots of folks here have said in the past.

I never had any issues running one on my previous DSM so not so sure why it is considered a band aid.

Thoughts?

Yes, the extended rod is garbage. The reason the fork needs to be in the position I mentioned before is that the fork can ONLY move so far before the end of the fork is hitting the passenger side edge of the square hole in the bellhousing and if its at this point and your clutch isnt disengaging, there is NOTHING you can do other than pull the trans back out, and either shim the ball or replace the fork and ball. Think about it, the hole in the fork where the ball seats wears out, and the ball itself wears down as well, thus putting the fork closer to the passenger side of the car and completely screwing up the geometry of the whole setup and you CANNOT tell if the ball and or fork are worn by looking at them, unless you know what the overall height of the ball is supposed to be when new, and what the depth of the seat for the ball in the fork was when new...
 
Awesome info, this was the XTD kit so hopefully the step won't be an issue. I think that I can put the tranny up and take a look to see where the end of the fork lines up. I don't mind taking a chance there. I just won't wait until the axles are back on to find out.

Thank you very much for your help.

Personally, Id buy new fork and ball, since shimming is really only a bandaid for a worn ball and fork, and, its almost impossible to visually distinguish a worn ball and or fork from a good one. The ONLY real way to determine if theyre worn, is when the trans is ON the engine WITH the new clutch and flywheel installed. You have to look at where the fork comes out of the tranny, and push the fork toward the passenger side so it puts the throwout bearing against the fingers of the pressure plate. (You will feel the fork stop against the fingers and it doesnt take much force) Now, look at the end of the fork. Is it angled more toward the PASSENGER side, or DRIVER side of the car??? A good fork and ball will leave the end of the fork angled toward the driver side; a worn setup will be opposite, or dead in the middle. If you dont want to buy a new fork and ball, shim the old ball and be done with it. Also, be sure that the flywheel step height is correct for the clutch you are using. Do this, or you will have to pull the tranny out again and it sucks, trust me



Yes, the extended rod is garbage. The reason the fork needs to be in the position I mentioned before is that the fork can ONLY move so far before the end of the fork is hitting the passenger side edge of the square hole in the bellhousing and if its at this point and your clutch isnt disengaging, there is NOTHING you can do other than pull the trans back out, and either shim the ball or replace the fork and ball. Think about it, the hole in the fork where the ball seats wears out, and the ball itself wears down as well, thus putting the fork closer to the passenger side of the car and completely screwing up the geometry of the whole setup and you CANNOT tell if the ball and or fork are worn by looking at them, unless you know what the overall height of the ball is supposed to be when new, and what the depth of the seat for the ball in the fork was when new...
 
Kchaazz is absolutely correct. You can't tell where the fork sits in the window until the tranny is mounted unfortunately (especially with non-factory clutch parts). So you won't know whether to shim or not until then and you may be taking the tranny off again. I went through this even with factory parts. The fork is the item that wears where it sits on the ball way way more than the ball wearing (fork is softer metal). I bought a new factory ball and it measured exactly the same as my old one which had been on there 8 years.

Read this: TRE TECH TIPS

and watch this "Pivot Ball Shimming" video: Jacks Transmissions LLC — Tech Articles
 
I would go ahead and shim the ball. It won't hurt anything and will only help. I have a stage II from TRE and Jon shims the pivot ball on his trannies.
It's all good. Make sure you lube the ball and the shift fork where it come in contact with the TOB.

Good Luck
Regards
Greg
 
Like others have said, mock it up, make sure it's within specs, and if it's not, fix it now while you have it out and have easy access to it.
 
Sorry to revive an old thread but I'm in a Shitty spot and need advice. I went with summits 12lb flywheel and a new oem clutch kit. It appears that my flywheel deck is short and I need to shim the pivot ball (my bad on not doing it while trans wasn't matted up but oh well) is it possible to slip a shim in through the fork window, then crank down the pivot ball? I really don't want to pull trans again just to slip a 1/8th inch washer on it. Has anyone ever done it without pulling trans
 
Also put a tiny amount of grease on the ball where the fork rides. Note: The fork wears more than the pivot ball (where it rides on the ball). But other things that change the horizontal alignment, like improper flywheel step height and clutch disk thickness and wrong PP, can often be corrected by pivot ball shimming. Shimming the ball is perfectly ok as long as the fork ends up in the correct position in the window.

http://www.teamrip.com/when_why_and_how_to_shim_pivot_ball_info.html

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Pic of my fork window: http://www.dsmtuners.com/attachment...-fork-shimmed-pivot-ball-at-0-071-jpg.148436/
 
I had an ACT 2600 and shimmed the ball just to prevent having to pull the trans if it didn't have enough stroke. I beat the snot out of that setup for probably 30kmi and never once had an issue. If i get around to doing another clutch ill be installing a new fork, ball and a shim.
 
I don't see how this can be done with the trans still mounted. Good thing you pulled it off. I've had great success with shimming the pivot ball on all my dizzums. One less thing to worry about.

I shimmed the ball while the trans was out. I meant that i didnt want to have to pull it again if i didnt get full disengagement.
 
How many washer should I use under the pivot ball? Thinking just one but do NOT want to drop trans again
 
I used one shim but others might use two or more. I'm sure someone else will chime in.

It's the stock trans, with an oem clutch kit, ACT streetlite 12lb flywheel. Had engagement issues before (why I'm shimming it) just want to make sure
 
A properly functioning clutch system needs no shim in my opinion. That means bled correctly, , master and slave are not worn out. Fork and ball are not worn out. These last two are most important. Flywheel step height MUST be right for whatever clutch you have and flywheel cant be cut severely. On a 1g the pedal asembly must not be worn. Rebuild if necessary. 2g pedal is a different design. I dropped a trans 8 times in one weekend chasing disengagement issues. This is also the reason I wont run a heavy clutch.
 
A properly functioning clutch system needs no shim in my opinion. That means bled correctly, , master and slave are not worn out. Fork and ball are not worn out. These last two are most important. Flywheel step height MUST be right for whatever clutch you have and flywheel cant be cut severely. On a 1g the pedal asembly must not be worn. Rebuild if necessary. 2g pedal is a different design. I dropped a trans 8 times in one weekend chasing disengagement issues. This is also the reason I wont run a heavy clutch.

True, shimming the ball can also be a bandaid for worn parts, however even a new fork and ball is not designed for these high force pressure plates. For me and others it is extra insurance.
 
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