Make your own flexplate?

I own a 1984 Dodge Caravan, 2.6 L Mitsubishi. I have replaced the motor
many times but never the transmission. Recently the flexplate broke
around the crank bolt holes and then 2 - 4 years later, my spare
flexplate broke. I assume this part has a twenty year life and it is to
be expected. My question is, could I fabricate one out of slightly
heavier guage (1/4 vs 1/8 inch) mild steel or weld a reinforcement to
the old plate and expect any results at all. I think replacement part
from the wrecker would have the same problem.
Thanks.

 

Yes, you can do it. But here are the gotchas:

1) Welding a reinforcement to the existing plate won't work
because it will just crack again, at the welds.

2) You are limited in how thick you can make it, if you make
it too thick it will drive the converter too far into the transmission
when you draw them together and it will jam

3) The plate needs to be balanced once you finish making it.

I would be surprised if the dealer does not have this part, have
you tried calling them yet?

Ted

 

Make sure when you remove the trans/engine you install the guide sleeves (or
whatever they call em) back into the block. If you leave these out they can
cause the engine to twist from the transmission and cause the flex plate to
break.

Glenn Beasley
Chrysler Tech

 

Note it is called a flex plate. That means it is meant to flex a
certain amount under a certain load. I'm guessing the engineers at
Chrysler figured this out to a reasonable approximation. If you make
the plate stiffer, then it will flex less under a given load which means
that something else will absorb that load. This part will then likely
fail ... and this part will likely be much more costly than the flex plate.

However, if you try it, let us know how it works.


Matt

 

If there is no ring gear attached to the flex plate (I know older
Chevys had the ring gear welded to the flex plate but MoPars did not) I
have heard tell of people making a flex plate out of several layers of
thin stainless steel. The reasoning behind this is that the thin
plates will be able to absorb flex loads better than one thick one.

good luck

nate