Driver side axle boot issues

At 110K miles, I had a Toyota dealership add a 3.5” front and 2” rear leveling “spacer” kit on my 2015 1794 Crewmax. They also installed some K02 LT305 22R20 tires and aftermarket wheels. It’s a street queen and rarely goes off road or into 4x4.
About 1000 miles later my driver side axle boot was leaking grease and they said the boot was bad due to age and I should go ahead and replace the axle since they had to pull it.
They installed a remanufactured Toyota axle and boot at that time.
Fast forward 2 years and 35K miles the boot leaked again due to it literally splitting and they installed another boot. 2500 miles later I hit a big tumble weed and it started leaking again. Changed it and after another 1000 miles it was splitting again. Changed it again. 150 miles later it’s split once more.
They think there could be a minor difference between the rebuilt axles and brand new. I told them they need to get the factory on the phone to see what’s going on.
They don’t think it’s the lift since the passenger side is still original and I’ve had zero leaks.
Any thoughts would be appreciated.

 

don't know why people still change boot, it's the same price as a new axle...

 

The boot should be stretched a little bit further out, if possible, so that the sides of the rubber peaks rub against each other less. Otherwise the friction eventually leads to failures.