Best transmission and internals to use for a budget 350 sbc swap? (Page 3/3) fieroguru MAY 28, 10:11 PM quote Originally posted by 88FGT: Say, I did some looking around, and managed to find another Quaife diff that could potentially work for the f40. The par number is QDF21B. The only thing I’m worried about is if this one is only designed for Euro-style f40 transmissions like the ones Saab or Opel uses. Is this true, or would this diff work across all platforms? Within the F40 production cycle, there are two different differential carriers: AWD and FWD. The AWD version has a splined output sleeve to drive the AWD unit bolted to the transmission differential housing. All the FWD versions share the same differential. quote Quaife QDF21B: Applications: Fits the following vehicles with GM F40 6-Speed Trans: 2006-2007 Pontiac G6 3.9L GTP, GT 2003-2012 Saab 9-3 Turbo 2010-2012 Saab 9-5 2011-2017 Buick Regal GS, CXP Turbo 2913-2017 Buick Verano 2.0L Turbo 2011-2017 Chevy Cruze 1.8L Ecotec Engine Wavetrac also sells a LSD for the F40. http://www.regalautosport.c...-gm-f40-application/