One other thing on trucks, I read the Pittsburgh Power guy on Ten Four magazine. He sells more power and better fuel mileage and says that a truck running in direct gear will get better fuel mileage than a truck running in overdrive. This is assuming the same engine rpm and rear wheel speed.

180Marty wrote:One other thing on trucks, I read the Pittsburgh Power guy on Ten Four magazine. He sells more power and better fuel mileage and says that a truck running in direct gear will get better fuel mileage than a truck running in overdrive. This is assuming the same engine rpm and rear wheel speed.

That is true, there's frictional losses involved with gear reduction. Not to mention added complexity.


All this CAT vs. 350 talk is in the hypothetical world of zero frictional loss. And bottomless bank accounts. Also, everyone gets a racecar.

In the early 70's a farm neighbor had a tag axle 59 chevy two ton grain truck and the 427 in it went bad. Another neighbors kid had rolled his Impala that had a 409. They bought the 409 and put it in the grain truck. It only hauled a couple 400 bushel loads out of the field before snapping the crankshaft off in front of the flywheel. The 409 car engine would spin the wheels off that Impala but when they were held down by a heavy load it tore itself apart.