90 AUTO TO 93 VERT AUTO PROBLEM

[bradturpin13]

After my 1990 250k automatic lost reverse, I hunted down a replacement...got one from a 93 vert. low miles! 10k

the 93 torque convertor bolts wouldn't line-up with my flywheel, so I inserted my old 1990 convertor.

now I have this wierd "whirring sound"
does anybody know what differneces these 2 transmissions have?
I assumed these transmissions to be the same from 90-96? is the fact it's from a vert make it different?
the convertors look a little differnet side by side and the obvious bolt pattern differneces.

Im thinking a new convertor for 1993 vert, and a 1993 flywheel? any insight will be appreciated...

please don't just say 5-speed swap!!!! not an option!

[biggie]

I know the ATs are different between '89-'90, '91-'94, and '95+. Probably would have to find an '89-'90 AT.

[bradturpin13]

everything about it looked identical....except the TC?
even the casting numbers.
the car pulls in every gear...just has has the noise.....I assume from the TC?

[bradturpin13]

was able to correct the problem using the 93 TC...and drilling 4 new hole in the flex plate... fyi