School Bus Conversion Resources

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norreh1 01-10-2014 12:47 PM

Picking the right train
Hello all, this is the first post. Been lurking around for quite a while trying to get my act together before making a big mistake buying the wrong buss. This sight is deff the sight for school buss conversions and the reason I decided to go with a schooly to convert. DW and I plan to build our home on wheels and move out of the stick and brick full time. Yes we have full timed before but moved back in the house with a foundation because of bad workmanship in the RVs we have owned. One of the problems Im having is deciding which drive train to avoid. Most of the busses I have found in the bird line are 5.8 cummins and a AT-545 My question is will this set up run the interstate pulling a jeep wrangler at 75 mph. I also found very cheap 1998 thomas saf t liner MVP ER with a 7.2 something diesel with under 100,000 miles that almost makes me want to buy a dognose instead of a flatnose which I perfer. Its that 7.2 something diesel that I know nothing about. Is this the V8 diesel like the 7.3 that comes in Ford pickups. If so I dont want another one of those. Had one in a F250 that was hard to work on the sides of that big V8 I rather have a inline six cyl. Could one of you guys tell me what the 7.2 is ? and what you have found running the 5.9 across country ? Also does the AT-545 Allison have enough gears to run the interstate at 75mph ? I dont want to have to start changing out ring gears and transmissions to put the buss on the road. I rather buy the right one from the start and keep it all stock as far as the drive train goes. Seems hard to find a 8.3 cummins with a MT643 around SC I would like to drive and look at one before placing a bid. I already watched a u tube of a guy pulling rusty panels off a buss he bid on no doubt with out looking at it. It looked like a nightmare. We dont have salt roads in SC in the winter but I know what Northern vehicles look like after just five years YIKES ! Im sure thats why they are so cheap in OH and NY

bansil 01-10-2014 12:58 PM

Re: Picking the right train
I have and can personally say this:do not get a 5.9 with a 545 if you plan any mountain driving at all esp. with a "toad"

East coast may be okay if you don't mind going slow (45mph to keep rpm's up 2200/2400) even then you will want an ext. tranny cooler) steep mnts will be 2nd gear 2200 rpms at 30 mph...with a load I would say 2200rpms in first at 10 mph...that's were I am now, going up 421 from N.wilksborro into Boone NC...slow and steady wins the race (8+% grade for almost 7 miles)

we drive all over TN/NC and I would never go west were I need a low gear(w/lockup),jakes or??? my bus would not survive a trip west...tranny would spit it's self out somewhere near mid-America

I would either budget for a 643 swap w/bell housing etc .. best bet for long hiway miles would be to get a bigger engine than the 5.9(it's a great engine...just not made for long miles with a crap tranny)

Ours works for us, short trips 350 miles-sh and we love 45/50 Mph hiways

oh welcome!!!!

norreh1 01-10-2014 01:56 PM

Re: Picking the right train
Does your 545 have four or five gears ? and yea I guess your right I just need to budget in changing out the tranny because trying to find the set up I want may be a hard thing to do. A little slower speed I can deal with breaking down beside the road not so much.

jazty 01-10-2014 03:54 PM

Re: Picking the right train
Just a quick note: working on the 7.3l V8 in a bus frame is miles different then working on one inside the cramped quarters of a pickup truck. I have an International with the T444E (7.3l Powerstroke with International's "trim") and with it being a dog nose I can practically walk around the engine, or sometimes even sit on top of it :) Just so long as you don't have to mess around with the up-pipes going to the turbo which are right behind the engine you'll be fine. Those are a real pain. It's no match for the dt466 or the Cummin's 8.3l, of course, but in my half-bus it runs like a top and with the 5-speed manual transmission it pushes up and down the hills at highway speed without an issue.

norreh1 01-11-2014 08:19 AM

Re: Picking the right train
I noticed a couple adds say 7.2 I guess thats the same engine as the 7.3 not sure. Does not give any more engine info. I wonder how the 444 would be in a flat nose. Yes I think Im with you on the dog nose set up with the 444 when the hood flips forward that would make a big difference. I drove a tractor trailer around the country governed at 65 for a while and that I could deal with as well as installing a large tranny cooler with fan. Just dont want to blow anything up. We would like to make a trip west and one north once a year but would not be in a big hurry. I looked at a lot of the big MCI and prevost type busses and that is just to big to get in and out of a lot of the campgrounds we visit. Tandem axles is a nono for me. Been their already. We are also trying to keep a tight budget on this build and stay under 7500 with us doing all the labor. I guess I have come to the conclusion to drive a little slower and take the long way home. Also the big buses that have been running the interstate have way more miles on them for way more money. It looks like I can buy a 5.9 AT-545 Bird or Thomas for about 3 Gs with under 150,000 miles. Even found a couple with under 100,000 miles but coming from up North I would say rust bucket not sure.

opus 01-11-2014 02:31 PM

Re: Picking the right train
75mph in a school bus? Mine will but gee, that fast for 25,000# of steel pulling a car. Aside from that, you wont find many school buses with power enough to do that speed.

jazty 01-11-2014 05:46 PM

Re: Picking the right train
Ahh. A Saf T Liner may be a Cat or Detroit Diesel. Check out this site for more info:

norreh1 01-11-2014 07:02 PM

Re: Picking the right train
Must be cat or troit cause I just went back and checked the websight hoping for some to pop up for sale in SC and noticed it said 7.2 L6 so I guess thats some type of 6 cyl. diesel. I rather stay away from cat they seem to have the rose royce syndrom I cant afford. I did drive a detroit 60 series for a while and hear good things about them but dont think they come in school busses. The search and learn gos on. Thanks to you guys that have replied. Each day I learn a little more. I have 2 or 3 months to find the right bus. What do you guys up north in the snow belt do about rust. Do you ever bid online with out looking over the bus ? Would a 1995 Bird be rusted out in OH. After looking at the Northern cars looks like in 15 years the frame and body would be rusted out. I will call the mechanics that service them but I just cant force myself to push that bid button.

JakeC 01-11-2014 08:16 PM

Re: Picking the right train
A 7.2 is a 3126 cat. You can find tons of info using google. Not a bad engine, it sounds like. I don't know a lot about it, though.

norreh1 01-13-2014 03:24 PM

Re: Picking the right train
Not trying to step on any cat toes but how come the cat form page is so small ? Is their not many cats in school busses ? Before I started researching on this websight I thought the 7.3 T444 powerstroke was the cats meow. Well thats was the only diesel I have ever owned. Humm sounds like a human, I own it so its the best. I try to stay out of that box and keep a open mind. I also thought Cats were one of the best diesels on the road bar none. Now after many hours on this sight not so sure. Whats up with the Cat ?

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