steering goes right, car pulls left when braking?

[STLSVT98]

I just finished replacing pass side axle and ball joint, the car was pulling to the left pretty hard so I took it in for alignment. Now the alignment is good the car tracks straight going down the road and under acceleration. But when I get on the brakes the steering wheel pulls to the right just a little but the car pulls to the left just a little, it is amplified the harder the braking and the higher the speed.
I did the 9-3 wiggle to check the tie-rods and they seem good, drivers ball joint was replaced about 10 mos ago. I checked with the alighnment shop and they said they didn't see any suspension problems while under there.

 

[crewchiefpro]

Pulling while braking is normally a caliper issue. One is sticking.

 

[STLSVT98]

what about the steering pulling the opposite way?

 

[zorrex]

Steering pulling can also be attributed to LCA bushing failure. Awesome job replacing the ball joints, but if the LCA bushings are still bad, you will still have the same problem.

Here is a visual example of what MY car did with bad LCA bushings/ball joints:

This situation would be more pronounced under braking. Hopefully this picture makes sense...

 

[B3NN3TT]

I was also going to mention the LCAs. Those bushings need to be tight.

When you accelerate hard, the wheels want to "outrun" the chassis, and when you brake, the chassis wants to dive between the wheels. The LCA bushings hold it in check. When one or both sides is weak, that wheel will "turn" when force is applied to it in the right direction.