1994 Dodge Caravan My front-left drive axle keeps popping o

I have a 94 Dodge Caravan. The left axle keeps popping out of the transaxle. I originally took it in to a repair shop because the car would shake when accelerating. They found the left drive axle was loose. I told them it had been replaced 5000 miles ago for same problem. They suggested replacing both axles. This fixed the shaking problem. One week later after 150 miles, the left axle pops out. They replace it and the 2nd one pops out after 200 miles. They tried a different manufacturer and this 3rd one lasted 400 miles. Each time I have asked if there is any other component that may be putting stress on the axle joint. They said the only other thing to do is replace the trans-axle. They don't do that at this shop, so I think they are being honest but maybe not smart. The trans-axle has 100k miles. The vehicle has 165k miles. Could motor mounts, ball joints, tie rods, alignment, suspension, struts/towers, etc cause this?