Opinions needed

[Dyehard]

Yes, they had some fluid in the torque converter and I added 1 quart to it before I installed it. I counted the 1 quart in the torque converter in my total added to the transmission.

 

[weaver735]

Is the c-4 kickdown rod adjusted properly that
controls pressure and shift points some aftermarket carbs don't have this lever or it is the wrong length also on rear if it is a 9" it will have a tag on one of the center bolts telling you what ratio it is.

 

[Dyehard]

The kickdown cable is functioning properly and I have an EFI setup off of a 93' Thunderbird. I will check when I get home but I am 99% sure the tag has been removed by a previous owner.

 

[Broncobowsher]

Tags are not always right. The last tag I had was for 3.54 gears but it was filled with 4.89s.

 

[DirtDonk]

So the sticker here is that the gearing was tested by turning the tire and counting the shaft revolutions. But there's enough question about how this is happening, that I would think revisiting the gear test would be a good thing at this point.
At least you can confirm your first test results were correct, but better yet would be to find out they were wrong and you do in fact have 4.56 gears.
Would be nicer than a trans rebuild at this point!

Even with that as an option, I would think it would be the last straw. Not because it sounds implausible, but because in all these years I've never heard of that happening with any transmission!
Anybody else ever heard of a transmission slipping that much?

Paul