system-f

I assumed since the engine is the same as the Dodge 12valves I could put this here.

I am looking at purchasing a school bus with the cummins 5.9 and an allison AT545 tranny. I have heard from several people that the 5.9 in a medium duty chassi such as a school bus (27k GVWR) was not a reliable engine. I really don't understand how or why this could be? I plan on towing about 8k with this vehicle and putting about 5k on the back of it which should be nothing for the chassi and drivetrain. Can anyone give any insite as to why the 5.9 not in a dodge truck might be sketchy?


TIA

MDMIKE

Not to Hi Jack your thread, but what model school bus (year/make) did this combo come in? A buddy of mine is looking to do the same thing you are for a tow rig for his Jeep and this sounds like it would be an interesting drivetrain combo to say the least. TIA for the info!

MIke

wannadiesel

Keith- The only people I've heard bad-mouth the B series Cummins in any application are on Ford sites. The 5.9 Cummins does very well in school buses. School bus service does tear those AT545's up though, when I worked for a large fleet in the Chicago area the transmissions were good for about 150k - but the 6.9 and 7.3 liter International engines blew up at 100k like clockwork.

system-f

Dave, thanks for the info, anything specific about the AT545, do you know if it has an OD? lockup converter? Is there a SAE #2 bellhousing on this cummins since it's medium duty?

Thanks again


Mike: There actually was my dream bluebird with the 5.9 cummins about 10 miles from me for sale for under 4k and less than 100k miles....too bad it's sold.. Try trucktraderonline.com and ebay.. also used-bus.com Plan to drive for the right bus. I am looking at lots all over the country, the only big deal is most buses are 10-15 years old , low miles, but in areas where they salt the roads alot. The bluebird TC2000 and other Blue bird flat noses used the cummins 5.9 a lot.

Haulin_in_Dixie

The commercial engine is stronger and more reliable.

wannadiesel

I believe it's a direct drive and I know it doesn't have a locking converter. Don't know on the bellhousing, H.I.D. would be better able to answer that. With the loads you're talking about in highway driving it'll do fine - it's the constant WOT stop and go driving that a school bus sees that tears them up. For good fuel economy you'll probably have to run 55, most buses are geared to run 60 - 65 MPH at governed RPM.

system-f

last question, I am a bit ignorant.. what is H.I.D.?

Haulin_in_Dixie

That's this transplanted Yankee in Red Neck Country!

wannadiesel

Haulin_in_Dixie AKA Murphy or just plain Bill.

Smokee

I know a fellow with a fleet of the busses. The weakest link is the torque convertor.

One of the busses took out an engine when it overheated because of a faulty water pump.

Barry Smith

Bill, how did you end up in God's country?

Haulin_in_Dixie

I put the snow blower on the trailer and headed south. When they started asking what that dang thing was on the trailer I knew I was home.

Haulin_in_Dixie

Actually my wives father was already here. I backed the reefer up to the door, loaded and came down. Then I had to take Midwest Emory's trailer back to New Jersey. Been here since, that was about 1970.