Volvo D12 Computer Info Wanted

It's easy to see which cummins ISX hp engine you have because of the spec plate on valve cover. Check it out. I decided against that Volvo D12 and got an ISX 500 in a 2006 Volvo vn 780. I couldn't help but spend the extra required for the spacious cab of the vn780, but the vn670 is also nice to drive. In any case, I ended up spending dyno money on both a 465hp Volvo D12 and on a 500hpCumminsISX, both in the same vn780 chassis and both 13sp (slightly different rear end ratios though). The Volvo D12 was dog. Nominally rated at 465hp, at the wheels 100 hp less--365hp. Although a 13 sp would help, I couldn't see myself restricted to such low hp hauling 80,000 lbs over the Sierra or Rocky Mountains. The Cummins ISX was better in performance, advertised at 500 hp, the computer suggested that the actual hp at the motor was better than 500, while at the wheels it was 440. I don't expect a huge motor, as I will drive below 65 and actually do want fuel economy, but some low hp motors can be frustratingly slow over mountains. The ubiquitous nature of the Cummins engine across the USA was also a big selling point for me. I'm still starting out, so who knows what life span the engine will have. The dyno process is somewhat of a gimmic, to be honest, the way dealers are chummy with your mechanic and all. Good luck in your venture.

 

No, I decided against the D-12 motor, not because it's such a bad motor but because the nominal 365hp as shown by the dyno, but still within specs understand, was just so much lower than I would want. Also, although Volvo is improving it's repair representation across the nation, it's still an exotic engine. I've found better results with a Volvo having a Cummins ISX 500 hp motor, which when dyno appeared to have 440hp at the wheels, and of course, Cummins is everywhere.

Independent inspection by a mechanic, even though it's allowable by law, including independent dyno work is not as easy to accomplish as one might think. The dealers and dyno guys all know each other, and with a wink and a nod, the dyno guy won't hesitate to manipulate his data to help his dealer friend out. There aren't any government standards for dyno testing of commercial trucks, like there are for smog tests on automobiles, which makes the dyno a deceptive artform.

Just be sure to look carefully at everything and find whatever oil leak, worn tire, or shock needs fixing by the dealer before it rolls off the floor. They can do these things cheaper than you. Look around. If the tires on one truck look better than another, get them to swap tires. I swapped for super singles this way.

Also, you can get the print out the pedigree of any truck for free at the Volvo and Cummins dealers--showing all warranty repairs made and remaining warranty coverage. Also, a computer ECM is useful for finding the amount of engine abuse--e.g. excessive water and oil temperatures--as well as the average mpg--but this will cost about $150 at the Cummins dealer, I believe. Work out a package with the Cummins dealer to do a dyno and ECM at the same time, but just make sure they know what hard copy results you require from the dyno.

Best of luck to you too...