Bruce you make good points. I am speculating about the software differences for two major reasons.Just out of curiosity, why do you believe that all software is the same between a 2500 and a 3500 Ram?
Have you got inside knowledge here or are you speculating?
I know that the transmissions are different and I know that the 3500 makes more power.
Bruce
#1 it would be very expensive to write a completely different software program for the 2500 and 3500, even though the vehicles have the same exact mechanical components.
#2 when Ram has TSB and software upgrades, it is the same "part number" for the 2500 and 3500. If they had different software, the updates wouldn't be the exact same.
I think there is a HUGE difference between European vehicles and the 3/4 and 1 ton trucks that we are discussing. Lets take the Ford series, which are IDENTICAL between the 250 and 350. The only difference between the 2 is an overload spring pack and a 2" taller spacer on the rear wheel. That is the ONLY difference. Is there any example of European vehicle where the vehicles are IDENTICAL and yet have different software settings? I would guess that no such thing occurs in Europe.
I am only comparing SRW trucks with the 68RFE transmission when I discuss the 2500 and 3500. As far as I know, there is ZERO mechanical difference, same exact rear axle, same exact rear axle ratio, same exact transmission (unless you opt for the Aisin in the 3500) and same exact power output of the engine. Only the DRW model offers the larger rear axle and different rations.
And yes... the engineers are chosen with specific performance goals in mind. For the 2500, the SPECIFIC goal is to keep it a class 2B vehicle, as I have stated. The class 2B rating keeps the GVWR at 10000 lbs or less. I'm not telling you to drive your truck any differently, I am only answering the OP's question that MECHANICALLY there is NO DIFFERENCE (other than 500 lbs spring pack) between the SRW 3500 and the 2500 with the 68RFE trans.