Do you make a product for the Ford 7.3L Powerstroke or Navistar International T444E engines?
No, Jacobs does not offer an exhaust or engine brake for these engines in fact, Navistar and Ford have requested that we do not develop one for these engines. The primary concern with putting a retarder on these engines is their use of hydraulic lifters. Most engines with hydraulic lifters have fairly low exhaust back pressure limits so the performance of an exhaust brake would not be substantial. More importantly the use of an exhaust brake on an engine with hydraulic lifters can cause engine damage. The problem is that the increased back pressure resulting from the operation of the exhaust brake will cause some degree of valve float. This valve float can cause the hydraulic lifter to re-set with the valve still open (not seated). This phenomenon is known as lifter jacking. Lifter jacking could also result if a traditional engine brake were used on these engines. The results of lifter jacking can be anything from low positive power (because the valves stay open) to engine damage cause
