[foreman00081]

Originally Posted by Tom S.

One would think so, but the way it was explained to me is that the Allison transmission and transfer case (I have 4x4) eat up a lot. The dyno measured hp at the rear wheels and didn't give a flywheel reading. That number is what the 'experts' gave me.

hmm, id be questioning the he!! out of those "experts" cause 130HP loss is impossible, if that were the case then a stock LB7 would only be putting down 170HP! that wouldnt even get these big trucks moving let alone tow anything and we all know what they can do towing. from what i saw at our clubs dyno day was that an LBZ (4x4 also) on a stock tune with only intake and exhaust and PPE boost valve (which wouldnt do anything on the stock tune) put down around 340 HP at the wheels and they are rated for 360 at the flywheel. so take away the maybe 20HP that you would get from the intake and exhaust and your still at 320RWHP or so which is right around 15% drivetrain loss. 15% loss is what i was always told is about the right loss for most vehicles from the flywheel to the wheels. what kind of dyno was it? ours were done on a superflo.