I have a 1986 Boyertown (Body) Trolley on a GMC School Bus Chassis, 8.2L Detroit Diesel, Allison 545 RM with a Rockwell International Differential with a 586 gear ratio, 10R-22.5 Tires.
I Have never owned a 8.2L aspirated Detroit Diesel. The question I have about the 8.2 Detroit is, when you take off from a dead stop the bus shift very well but when you hit four gear you are going 40mph, from 40 mph to 55 mph the engine is so noise that you cannot hardly hear inside of the bus the rpm are so high that it sounds like the engine is going to blow up. You let off the accelerator at 55 mph the bus will pull down in speed right away, the buses I drove with AT 545 when hitting four gear you can take foot off accelerator and bus does not pull down right away until you start braking
What can I do to fix this. Please Help!