Hi

car info: 2014 hyundai elantra gt, with 150k miles

Recently I changed the front axles with aftermarket ones. immediately after that, I started hearing shuttering and pumping noises from under the hood whenever I press brake pedal, up to around 35 mph, the ABS light will activate and the noise will stop. the car will skid with hard brakes.

I returned to the shop, they ran a simple scanner and the following code appeared:

C1207 Rear left wheel speed sensor intermittting/out of range.

I replaced the the sensor with an original one with no luck, same code, the shop told me it would be the reluctor wheel so I changed it also with no luck. 

Then I moved to another shop, they ran a scan with a more sophisticated tool, and found that the reading from the rear left speed sensor stuck at 158 mph, while other 3 are in sync. they concluded that the abs module is gone, and quoted me thousands to replace it with a new one.

what could be the problem? 

thanks in advanced