broken flex plate , twice ????

[chavito]

Hello, new to the forum. I'am trying to figure this out. I have a 96 explorer, 4.0L auto 2wd. First time, the center of the flex plate seperated completely in the center where the crank spacer sits.The torque converter got some external damage (scraped) I replaced the flex plate and crank spacer. 5 months later, same thing , except I caught it before the flex plate broke completely. All replacement parts from ford, flex plate, crank spacer, torque converter. Third time, same concern. The flex plate has broken perfectly outlined around the crank spacer. Has anyone seen this ? Any ideas ? Thanks

 

[boominXplorer]

yeah thats the reason in 98 I beleive ford went to a 8-bolt flexplate.

 

[Glacier991]

There can be a cause that few regognize... the transmission should snug up to the back of the engine without having to be pulled into place by the bolts. If the TC in not the right one, is installed incorrectly, or the input shaft not the correct one, there could be a slight interference preventing the Bellhousing from coming up flush to the back of the engine. Sooo, you torgue it into place with the bolts cuasing stress around the pilot in the center of the flexplate.

Time, vibration and continued pressure around that center WILL break the plate.

Mind you I am not saying that's the cause for your failure, but just that I HAVE seen that happen and JUST for that reason before.

 

[Wrench]

Chavito - what was the first indication you had of a cracked flex plate - vibration or noise from flywheel area?

96 Limitedx- would you happen to have the contents of that TSB on the updated flex plate?

 

[chavito]

Thanks for the replys. I'am guessing I installed the updated flex-plate since I replaced it not that long ago. I'll have to talk to someone at a dealer and compare part #'s with the tsb (tech service bulletin ?). I was also considering something in the tranny causing this. The trans was rebuilt about a year and half ago. Thanks again.

 

[chavito]

The noise was a rotational knocking type. It sounded like the converter was smacking the inner bellhousing and was louder under accceleration. The converter did get damaged, spinning when the flex-plate center broke off. That updated flex-plate part # would help .

 

[mechanix]

I have seen this problem a few times. What I have seen kind of goes along with what Glacier said in his previous post, one of the alignment pins was missing when the engine or trans was replaced. This is often a common item to over look when this type of a problem arises.

Eric

 

[checkedout]

Just replaced mine for the second time in three months! Third time over all. I wish I knew the cause! Dealer doesn't know either.