Parallel to the five 4-4-0 with the numbers 659 to 663, the Lehigh Valley had five 4-6-0 built by Baldwin in 1895 and gave them the numbers 708 to 712. These were all Camelbacks and were nearly identical apart from the additional driving axle. They were completed by 20 other 4-6-0 with a slightly smaller boiler. The first of those also got a driver diameter of 68 inches, while the other 15 only had 62 inches.

Later when the new class scheme was adopted, they all got the prefix J, what denoted their wheel arrangement. The locomotives with 62 inch drivers were classed into class J-42, while the ones with 68 inches became class J-43. After rebuilds which changed boiler pressure and cylinder size, they were designated classes J-49 to J-52. The last ones were scrapped in 1930.