I recently installed the 231mm tundra brake upgrade on my 3rd gen with the stainless lines to go with it. After this I noticed my tires seem to lock up and slide very very easy. If the road is not dry and if there is any gravel or dirt on the road the tires lock up with little effort. Could this be related to the ABS system?

 

If the ABS is functioning, the brakes should pulse and not lock up except at near zero speed.

 

What end is sliding? Front or rear tires?

Do you have an ABS warning light on the dash?

Dunno, I have the 231mm Tundra brakes on mine, have had them for a long time. No real change in braking performance, other than the Tundra brakes don't get warped and start shuddering and pulsing through the pedal.

Did you spill brake fluid on the pads during the install? Contaminated pads (or shoes in the rear) can be very grabby.

 

No ABS light on the dash, front brakes. No contamination on rotors.