I know that it is mainly a FS2004 problem but maybe someone has anidea.When I use the PMDG 737 e.g. in the caribbean or pacific region the OAT on T.O. is mostly around +30 deg (dunno Farenheit).I use either the online weather option with 15 min updates from FS2004 or ActiveSky2004.On both the OAT at higher flightlevels seems to be to high so the 737 on normal loads (e.g.737-800 61 t.) climbs like an ashtray with 800ft/min at FL 200 with OAT of + 12 deg.In other regions like europe it

I think poor climb performance with the 800 is a known issueHave a look around the posts and you'll find some info. I think it will be addressed in the forthcoming update.