The engine was dangerously prone to overheating and suffered from connecting rod or bearing failures. Gasoline leaks from the fuel pump or carburetor, as well as motor oil leaks from gaskets easily produced fires in the engine compartment; several were destroyed in such fires. Transmission and final drive breakdowns were the most common and difficult to repair. A large list of other problems were detected in these early Panthers, and so from April through May 1943 all Panthers were shipped to Falkensee and Nuernburg for a major rebuilding program. This did not correct all of the problems, so a second program was started at Grafenwoehr and Erlangen in June 1943.



Due to enemy action and mechanical breakdowns, the combat strength sank rapidly during the first few days. By the evening of 10 July there were only 10 operational Panthers in the front line. 25 Panthers had been lost as total writeoffs (23 were hit and burnt and two had caught fire during the approach march). 100 Panthers were in need of repair (56 were damaged by hits and mines and 44 by mechanical breakdown). 60 percent of the mechanical breakdowns could be easily repaired. Approximately 40 Panthers had already been repaired and were on the way to the front. About 25 still had not been recovered by the repair service ... On the evening of 11 July, 38 Panthers were operational, 31 were total writeoffs and 131 were in need of repair. A slow increase in the combat strength is observable. The large number of losses by hits (81 Panthers up to 10 July) attests to the heavy fighting.