Advise for good highway bus

[grin61]

I'm new to this forum, and I've been thinking about converting a a
school bus. Started looking through the for sale buses and I know what type i'd like just not sure which engine -drive train would be best. I like the RE Thomas HDX and the Blue bird All americans. I was thinking around 2000-2005. I see they came with several different engines and I'm trying to make sure I get one that would allow me to cruise the highways at 65-75mph, would also like it to do well in the mountains. Do I need the 8.3 cummins and a six speed allison? Also seen a couple of reasonably priced Thomas's with the MBE 906. I just want to make sure I start with the right platform before putting the time into a conversion. Appreciate any advise from you more experienced folks.
Thx

 

[brokedown-SKO]

1. Adjust your year range to 2000-2003 unless you're specifically aware of and prepared for the problems with EPA2004 engines
2. The transmission and rear axle ratio are more important for highway speed than the engine.
3. Most 6 speed transmissions in buses are electronically limited to 5 gears. Some are able to be unlocked by third parties. Some people have had success getting 6th unlocked through official channels with Thomas buses, to my knowledge Bluebird doesn't do this.
4. Nobody buys a MBE906 because they wanted an MBE906, they end up with one because they otherwise liked the bus. Most of those buyers were unaware and unprepared.

 

[Sehnsucht-SKO]

If you're in the market for an RE then you have a few options. Thomas buses will have either a Cummins 5.9 or 8.3 or a CAT engine if you have any preference on engine brand. Blue Birds will probably also have the same options. IC brand is International/Navistar so most likely will have a Navistar or MaxxForce engine. Some people prefer these because they're already familiar with Navistars and their cousin engine the PowerStroke used in Fords. I think most people will steer you away from the MBE because its kinda rare in the US so can be pricey for parts and labor and less experience with them means you'll feel isolated for feedback.

With any of these configurations you'll probably end up with an Allison MD3060 transmission. There's a super-long thread about unlocking 6th gear because by default these are electronically limited to 5 speeds in school bus applications. 6th doesn't get you a lot more speed, just better fuel economy to cruise at highway speed. The differential is going to dictate more your comfortable cruising speed. If possible, look for an activity bus which was probably spec'd to run highway versus a daily route school bus. A key hint for these is often the belly boxes for extra storage. Also if you're lucky enough to find one from a school that had $$$ it may not be yellow and have the flashing lights, saving you the trouble.

I think everyone here will advise nothing later than 2003 which is when the added emissions started being installed which adds cost and complexity. If you already have diesel experience you may know these as DEF or EGR systems which like to trigger engine lights and kill your power output every time they want attention.

Hope this helps

 

[WIbluebird]

In order of most desirable to least desirable my list would look like:


Cummins 8.3
International DT466(E)

Cat 3126
Cummins 5.9
MBE
CAT C7



Work on the street is that the MBE is a decent, reliable engine but finding parts and service for them can be difficult as they were only sold for a few years in the States. Buses with MBEs go very cheap because of this.

 

[Sehnsucht-SKO]

In order of most desirable to least desirable my list would look like:


Cummins 8.3
International DT466(E)

Cat 3126
Cummins 5.9
MBE
CAT C7



Work on the street is that the MBE is a decent, reliable engine but finding parts and service for them can be difficult as they were only sold for a few years in the States. Buses with MBEs go very cheap because of this.

I approve the order of this list ;-)

 

[Drew Bru]

Aside from the engine, you'll want to look at the transmission and the gearing. You'll want something with highway gearing and a transmission with a lockup torque converter (which rules out the Allison AT545). Like Sehnsucht said, look for an activity bus...used for transporting school athletic teams and bands and whatnot. They usually have storage bins. As to where, geographically, to look? I'd look at Colorado, Wyoming, Utah or other Rocky Mountain states or the Pacific Northwest. You want the right platform to build on, so avoid the rust belt of the midwest and northeast.

 

[SolomonEagle]

Get a cutaway/van bus

 

[PNW_Steve]

I approve the order of this list ;-)

I do as well but there is one missing. The DT-530 is a very well regarded engine. Not nearly as common as the 466 but definitely deserves the #2 or#3 spot on the list.

OP: It is awesome that you are approaching this with an assessment of your needs and looking for a bus that fits your needs. I see too many: "I bought this low spec bus for too much money. Now how do I make it a good travelling bus? "

I have the 8.3 Cummins, MD-3060 and 5.29 rear gears. In 5th gear I run 65 mph @ about 2200rpm. Personally, I don't need to go any faster but I would like to get my cruise RPM down closer to 1800RPM so I am going to have one of the 3rd part shops unlock 6th.

Good luck with your quest.

 

[EastCoastCB]

I'm new to this forum, and I've been thinking about converting a a
school bus. Started looking through the for sale buses and I know what type i'd like just not sure which engine -drive train would be best. I like the RE Thomas HDX and the Blue bird All americans. I was thinking around 2000-2005. I see they came with several different engines and I'm trying to make sure I get one that would allow me to cruise the highways at 65-75mph, would also like it to do well in the mountains. Do I need the 8.3 cummins and a six speed allison? Also seen a couple of reasonably priced Thomas's with the MBE 906. I just want to make sure I start with the right platform before putting the time into a conversion. Appreciate any advise from you more experienced folks.
Thx

The gearing is the most crucial element in how fast a bus can go. Even a wimpy engine can propel a bus to 80+ with the right gearing.

 

[EastCoastCB]

In order of most desirable to least desirable my list would look like:


Cummins 8.3
International DT466(E)

Cat 3126
Cummins 5.9
MBE
CAT C7



Work on the street is that the MBE is a decent, reliable engine but finding parts and service for them can be difficult as they were only sold for a few years in the States. Buses with MBEs go very cheap because of this.

I like the list. I'd put it as-
Cummins 8.3
DT466
Cat 3126
Cummins 5.9
T444E
MBE

I left the C7 off cause I don't mess with ANY after 2003/2004. YOu all can decide if you want to play that game but I'm not gonna!

 

[grin61]

Thanks for all your replies. You guys have confirmed what I thought.....but I only know enough to be dangerous! I'm just starting this process and it will be several years as my wife has forbid me from starting another project until the house renovation and Argosy restoration are complete. In the mean time I will follow this group and hopefully learn as much as possible before we take the leap!

 

[o1marc]

Argosy? Airstream? Trailer or MH? What size. I found one for a buddy a couple years ago. My finders fee bought my first bus.

 

[grin61]

'78 Argosy trailer (made by Airstream) Pretty original inside but we've put a lot time into bringing it back.

 

[jctrembly]

My bus is listed for sale and is set up for interstate running. Come take a look, you don't want anything with EGR valves or emissions control's unless you really want to pay alot more for no reason.

 

[Willie_McCoy]

I like the list. I'd put it as-
Cummins 8.3
DT466
Cat 3126
Cummins 5.9
T444E
MBE

I left the C7 off cause I don't mess with ANY after 2003/2004. YOu all can decide if you want to play that game but I'm not gonna!

I have got to throw my hat into the ring here, my personal ultimate school bus engine list would be similar, with just a few additions on the top...

Cummins 855 Big Cam
DD 671T
Cummins 8.3
DT530
DT466
CAT 3126
Cummins 5.9
T444E
MBE

I will admit the first 2 aren't likely to be found without going looking for them specifically, but they still are tops on my list.

 

[1dmpo]

When you get those 03-04 buses nothing is written in stone. Mine is titled as an 04 but was built in April 03 and when I had it at the Cat house to have it turned up they said the engine serial number checked out as an early 02 manufacture date. Go figure. Never hurts to go check one out in person to see with your own eyes what your looking at. My Thomas has a 3126 with md3060 that is unlocked with 5.67 rear gear and 11R 22.5 that are 40" in diameter. No tach on the dash but Cat turned it up to 2640rpm and it tops out at 80mph. Cruises nice at 65-70. Maybe that will give you an idea what you're looking at when you start looking.