The torque converter must be properly indexed in the transmission. There are three 'clicks' on a perfectly indexed converter - the first when the input shaft indexes, the second when the stator indexes and the third happens when the front pump indexes. You may think it's fully indexed, and indeed the converter will fit between the flexplate and transmission (without binding) if the input and stator are indexed but not the pump. It's easy to miss if you're not 100% careful, such as if you're in a hurry to get it on the road; I've been guilty of that myself once which is why I can write about it here. I hope you don't view this post as a knock on your skills - it isn't.
A failure of this type is considered an install failure, not a build failure, so your trans tech is not responsible if you installed the transmission yourself.
Of course, this is all hinging on whether or not the front pump (broken gears) is the problem. There are other things that can cause this - low oil level (did you put at least 8 to 12 quarts of fluid in it when you installed?) is a chief culprit.
8 quarts if you're reusing a torque converter, 12 quarts if you have a new/rebuilt converter.
__________________
1988 9C1 - Modified LM1 @ 275HP/350TQ - TH700R4 - 3.08 8.5" Disc Rear - see it at
http://www.silicon212.org/9c1!
2005 Crown Vic P71 - former AZ DPS - 4.6 liters of pure creamy slothness!
1967 El Camino L79/M20 old school asphalt raper
Remember - a government that is strong enough to give you everything you need, is also strong enough to take everything you have.