Well... I figured it was a matter of time.. and I was right.

I've been getting a lot of rattling/banging from the TC/flywheel over the past couple weeks.. I originally thought it was rod knock.. then it sounded like timing chain slap.. and then when the vibrations started, I realized it was my TC.

This morning on my way to work, I got about a mile from my house.. and GRRRIINNNDDDDDDD CRUNCH....

I quickly slipped it in neutral, shut off the engine and coasted into a parking spot.. I started the car.. no noise.. no usual TC slap from the start.. uh oh.

I give it a rev.. wow. revved WAY too quickly.

Put it in reverse... haha. nothing.

Yup, just as I assumed... The TC broke off of the flywheel. I haven't had a chance to assess the damage (still at the office..) But I think it could be a few things:

* Lost TC bolts. TC/Flexplate/FW still fine, only new bolts needed.
* Sheared TC bolts. TC/Flexplate/FW still fine, not sure if I can remove the bolts.. that sounds interesting...
* Cracked flywheel?
* Broken flexplate?


I don't have experience with transmissions/TCs.. I have always had a shop do it in the past.. I'm running a heavily built 700r4 with a TCI 2800 stall.

What should I check for when I get the car home. What steps to remove the TC? Is there a tech article on this?

TC installation, how hard is it? What do you do.. is it an afternoon job that I can do shade tree style? Or is this going to get messy...

When replacing the TC is it reccommended to do a new FP and FW? How much do those run?


Just need some pointers... thanks in advance

-Ben

 

First off auto trans use a flexplate only no flywheel. You need to remove the plastic inspection cover & see what happened, at best you will need new bolts. At worst flywheel, TC, crankshaft, ??
I have done all the above in my driveway with basic tools. If you aren't real handy at this, I would have someone else do it.

 

ah, that clarifies the FW vs FP thing


as far as how they connect


The FP is bolted to the crankshaft, and then using different bolts the TC is connected to the FP, correct?

Just wondering if the bolts broke off INTO the FP, or into the crankshaft...

 

i'm curious to hear what you find when you take that cover off. from my experience when a tranny just dies like on you it's never something simple. i hope you have a good warranty on that trannsmission. good luck!!

 

well, i know for a fact its converter/fp related... The trans itself is rock solid...

 

Sing along if you like, The crankshafts connected to the flexplate, The flexplates connected to the torque converter, the torque converters connected to the trans front pump & input shaft. You could have a failure at any one or several of these points.

 

ahh.. I gotcha now.

Does the FP bolt to the crankshaft from the FP side, or from the CS side... just wondering on the bolt setups.. a pic would be priceless


Also.. what is the difference between a flywheel and a flex plate, other than the name...

 

A flex plate is a piece of stamped sheet metal. A flywheel is a casting or forging about ½" thick or more.

Either kind bolts to the crank from the rear. Bolts go through them and thread into the crank flange.

More than likely your flex plate is cracked around the crank flange; a very common failure mode in cars of all brands. Many cars have been junked for cracked flex plates, from people thinking their engine was blowing up.

To replace the flex plate, all you have to do is unbolt the TC from it; remove the bell housing bolts, and replace 2 of them with real long ones, about 6" or so work well; remove the drive shaft, and the trans mount and torque arm mount, and anything else that might be in the way; and slide the trans rearward far enough to get a wrench in there to R&R the flex plate bolts. That way you dodge the issues of having to remove the trans, drain fluid, etc. etc.; although it would be a great idea to have a plug for the rear of the trans, to keep the fluid in when you pull the drive shaft.

 

Thanks.. that's the info I was looking for...

How much do flexplates run? Do they make lightened ones like they do flywheels.. or is the weight of it not a siginificant factor since they are thin to begin with?

 

Never saw a lightened one. The majority of the rotating mass is in the TC & the oil it contains. You could lower the mass by going to a 9" performance converter.

 

you can get a nice/cheap balanced SFI approved flex-plate from TCI for like $80.00

If the converter bolts just snapped off and the flexplate is free-spinning then you are very lucky. I would say somthing happened to the flexplate as well, just because murphy sucks. if somthing happened to the crank side, which doesnt seem likelly, your in for trouble. but thats unlikelly since you say the engine revs fine and sounds normal at idle right? right? This would indicate the engine is ok thus the crank is ok... meaning flexplate / converter / trans related problem. if its the trany, which you also doubt, then it could be anything. This problem will probably cost $150~~ if its NOT the tranny. even if you flexplate looks good, i would still replace it with a balanced / brand new one, it couldnt hurt right! and next time use locktite / <b>ARP</B>converter nuts to hold it in place, those wont break! If there was a nuclear explosion on top of your car the only thing left would be those bolts! ARP rules!:hail: some people just screw the bolts through the flexplate into the converter... big no-no, Every time somone does that they seem to come loose and angle themselves and snap... is this how yours was done? I've had bad luck with that sort of thing as well.
Good luck!

 

Yeap, 9 times out of 10 if one of those grade nothing flex plate bolts comes lose (even if you have a kick *** SFI plate) it's crack city. That crack over time turns into a full donut all the way around.
Been there to many times to count. Get those ARP's TC bolts like 'Kingtal0n' said !!!, and lock tight the crap out of them. I even use ARP crank bolt also.

BTW: On the crank bolts, while the trannie is moved back get a long 11/16 wrench. While your at it get a flex plate turning tool. I bought mine at Checker for cheap. It makes doing the bolts on the TC much easier. Oh yea, don't tighten them until all three are started or you won't get them to line up. Just hand tighten them one at a time, and then touque them as you get to the first one again. See why the turning tool is handy


Ron