hello im a long time lurker but I have an issue I wanted to get some thoughts on. i have a 440 swapped power wagon it was a budget built 440 i used the original crank because it looked to be in decent shape. i rebuilt the 727 had to put an 86 4x4 output shaft in a 78 2wd bb housing. am running an hd hughes 2500 stall converter. now after break in i kept finding glitter in the oil after trips turns out it had been wearing the thrust bearing so badly the crank started to contact the block. now i just replaced the crank and oil pump and am trying to track down why it failed. note it is a 68 block witht he small thrust surface. i checked my cooler line pressure from the trans and get under 20 psi at the inlet at an idle but in gear loading up the converter i can see 70-75 psi on the inlet to the trans cooler most i get is 30 psi on the outlet side. i thought you werent supposed to see more than 30 in the whole system. is 70 enough to cause thrust bearing issues?

Pressure can be caused by a resistance to flow , I would be looking at your cooler as a restriction if you see 75psi .

also check to make sure the convertor is not pushing forward against the crank.

had to push the convertor forwards to bolt up to the flex plate and with everything bolted up i do have end play on the crank. i am replacing the trans cooler regardless. il check the pressures when i do i just wonder if this would be enough to take the crank out

Since it's a '68 motor, it should have had a forged crank and be internally balanced. Sure you have the right balancer and flexplate on it? There's no weight on the torque converter right? Stock LY rods?

The first thing to know about thrust bearings is that they have to be set.

The second thing is that thrust bearing design has advanced lately, the better ones have little ramps that help to establish the oil wedge.

R.

stock rods it is a steel crank with the correct converter/flex plate I did set the thrust bearing when i assembled it. it seems strange i still had 30 psi on the outlet of the trans cooler going back to the trans. it is the factory steel line and i dont see it kinked anywhere thought it just drained back to the pan