Pennsylvania Title 75. Section 3313. Subsection D.

Driving in right lane. (1) Except as provided in paragraph (2) and unless otherwise posted, upon all limited access highways having two or more lanes for traffic moving in the same direction, all vehicles shall be driven in the right-hand lanes when available for traffic except when any of the following conditions exist:

(i) When overtaking and passing another vehicle proceeding in the same direction.

(ii) When traveling at a speed greater than the traffic flow.

(iii) When moving left to allow traffic to merge.

(iv) When preparing for a left turn at an intersection, exit or into a private road or driveway when such left turn is legally permitted.

(2) Unless otherwise posted, no vehicle or combination over 10,000 pounds may be driven in the left-hand lane of a limited access highway having three or more lanes for traffic moving in the same direction except when preparing for a left turn at an intersection, an exit or into a private road or driveway when such left turn is legally permitted.

(Apr. 29, 1994, P.L.148, No.25, eff. 60 days; June 25, 1999, P.L.164, No.23, eff. 180 days; June 26, 2001, P.L.734, No.75, eff. 60 days)