other differences that should be noted is that the 2004r uses 3 sets of planetary gears to get 4 forward speeds and one reverse and the 700r4 uses 2 sets of planetary gears to get 4 forward speeds and one reverse .the 700r4 uses 2 seperate sun gears to accomplish this and uses the sun gear for input verses the ring gear in the 2004r which follows most conventional designs using a compound sun gear .in my opinion the 700r4 also absorbs less horsepower than a 2004r and can be built to withstand the same if not more torque loading than a 2004r .the 700r4 has a much greater band apply surface especially when using a wide band,and the direct clutch pack is more efficient because of the fact that the drum doesnt have to be accelerated from a stop to initiate hi gear as the frictions are always spinning with the input housing .this reduces effort to initiate direct drive and shortens application time.a 700r4 can be very effective with normally aspirated engines with wide lobe center angles that have slightly wider power bands by putting the engine on the torque curve during gear changes increasing acceleration potential .we are currently in production of a steel input housing and reaction tube that will really allow even more torque potential for this very respectable well engineered four speed automatic.in stock form a 700 is definately stronger tan a 2004r.