Blew out the trans pump... 3rd time!

I had the trans shop do a race build up with all upgraded internals. New Midwest 2800-3000 stahl. Lasted about a year and blew the pump 1st time. Had them replace it, go through the trans... did it again. Replaced it again, put a new flex plate in and a month later completly destroyed it again. This time I knew that something was wrong because it was not shifting into 3rd @ wot and in OD or 3rd with the converter locked up the rpm's would rise as I tried to slowly accelerate... just like barely riding the clutch in a manual. kind of felt like the converter was slipping. But it only did it when the trans got to operating temp. Any ideas??? Any one else have this problem?
All mods in sig.

There may be something wrong with your crankshaft where the converter pilots in. The register bore may have a burr that is keeping the converter from sliding all the way forward. Does the converter fit flush against the flexplate before you bolt it in? Has the car/engine always had an automatic?

If I remember right there were washers to space the converter when I got the car.Not sure if that helps. I got the car about a year ago so I'm not sure if it has always had an auto. I think it is factory. Doesnt look like it was converted.

Who is doing the install? This sounds like an installation problem.

Rich

If I remember right there were washers to space the converter when I got the car.Not sure if that helps. I got the car about a year ago so I'm not sure if it has always had an auto. I think it is factory. Doesnt look like it was converted.

Therein may lie your problem. I would check and see if the washers are still there. If they are then your converter for some reason is unable to slide into the crankshaft all the way to meet the flexplate. The shop may have also just tightened the bolts down putting the flexplate in a preload situation. During engine operation the flexplate flexes (surprising I know) fore and aft, moving the converter with it. If the converter is unable to move forward, it may be bottoming out the front pump. The hub of the converter is keyed to the pump gear and any load on that gear is going to burn up the pump. The other thing it will wear is your crankshaft thrust bearing.

Who is doing the install? This sounds like an installation problem.

Rich
1st time was a buddy/ASE certified mech. Then the trans shop has had it out the other 2 times.

Therein may lie your problem. I would check and see if the washers are still there. If they are then your converter for some reason is unable to slide into the crankshaft all the way to meet the flexplate. The shop may have also just tightened the bolts down putting the flexplate in a preload situation. During engine operation the flexplate flexes (surprising I know) fore and aft, moving the converter with it. If the converter is unable to move forward, it may be bottoming out the front pump. The hub of the converter is keyed to the pump gear and any load on that gear is going to burn up the pump. The other thing it will wear is your crankshaft thrust bearing.
Exactly what washers... the ones between the flexplate and converter? The shop said that those did not need to be in there. I trust them because they have done literally 100's of other F-body rebuilds so I know they have experience. I was just a little confused because my buddy who put it in the first time said the washers were needed.
Strange thing is I made it almost a year and about 10,000 miles, and 6 passes @ the track before this problem showed up. Right after I had it Dyno tuned.

Anyone???

Yes, I was referring to the washers between the flexplate and converter. They really shouldn't be there. I have seen that done when the converter wouldn't slide all of the way into the pilot of the crankshaft as it should. The shop repairing the pump should ultimately be able to diagnose the issue and correct it.

That is what I'm hoping. I kind of think that it might be the tune somehow. At the same time as the tune, I also had a new pcm installed. Burned my other one out. So the new one was completely re-programmed. Like I said before, the set up went about a year trouble free, then within a week of the tune/new pcm, I have went though 3 pumps.