Originally Posted by rty12345rty
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!
I have almost the same set up but mine is on a ford chassis.
8.2,545 and an eaton rear with 6.50 gears.
I only get 49mph.
I put the pedal to the metal and am a little slow off the line and am in 3rd gear by 25 and hit 4th around 35-38 and my 8.2 is loud.
I insulated inside and am working on the firewall and the backside of the dog house and it has helped some but I don't think we will ever really silence it down anymore.
One other thing I have an idea about and others have done it is to build a removable console over the dog house and maybe insulate it on the backside also.
To me the only way to quiet things down is to create layers to break/muffle the sound
All of the old 8.2 mechanics I have talked to say not to adjust the governors on the 8.2 that they are set for what the motor is designed at RPM wise.
My cheapest options are to change rear ends/gearing down into the 4.? Range and my tires are 9r20 tubed Dayton rims so I have been told by a few tire shops the 10r22.5 tubeless will fit my rims but looking at my rims I think I have to stay with tubes because the valve stem opening is a 2-3" long slot. Or maybe new rims are needed to upgrade tire size and whatever that gives me is what I get unless I hit the lottery and then a new power package and a lot of other wet dream ideas? It breaks my heart to waste 2$ on a ticket so I guess that part is another dream