Truck is pulling right on when I brake after installing new to me tires. Tires have about 10k on them. Drives strait and after mounting and balancing the tires the truck pulls right after braking. Alignment tech recommending replacing brake lines but the only started happening after I mounted the tires.

Bad balance?

A friend who used to work for tire shop recommended rotating and seeing what happens.

Any ideas?

Most likely tire pull .

Most likely tire pull .

??

Trade the left front wheel and tire with the right front wheel and tire and see if the pull is changed in any way.

Many times a tire can develop a sloped treadwear pattern when run on a truck with bad suspension parts or a poor alignment.

Yup I agree swap front 2 tires and see what happens.

Had it into Les Schwab today and nothing obvious, calipers are releasing just fine and tires look fine. I dropped it off so I'm not certain if they actually swapped them or not. I can handle that myself though on Saturday.