Might want to grab a snack and a drink – a lot of information here. Just a good run-down of what to expect, what to look for, what to stay away from, and what to know.
Just some things to consider before you go shopping for a bus.
How much vehicle you can handle driving.
How and where you plan to use it.
How often you plan to to use it.
What you plan to do in your conversion.
Not all buses are created equal. I have included info on larger ones as well, just in case you decide a larger one is in order. You have several different types – mini buses based on full-size cargo van chassis, flat-nosed (similar to a transit bus – these come in front and rear-engine versions – a consideration in and of itself), and the old familiar standby – dognose (conventional) buses, which are based on Class 7 truck chassis, similar to their flat-nosed / transit brethren.
Some are air brake, some are hydraulic, some have manual transmissions, others automatics, some are gasoline-powered, others are diesel. There are even some LPG / CNG / hybrid units out there. All have their nuances, and there are things you should know before choosing a bus, and proceeding with conversion.
Space, for instance, is a huge consideration with the smaller van-based buses, and for that reason, depending on your intentions, you may find after consideration of this that a larger short bus may be more suited to your needs. For instance, you mention traveling cross-country. You may find that a smaller bus may seem a bit more cramped than you thought. Smaller minibuses ARE available in longer lengths -- when you can find them. They range anywhere from 12-22 passenger.
If that means mountains (likely), I also wonder whether these would have enough power to climb mountains reliably in such a scenario. Overheating is always a possibility. I would highly recommend a manual (most minibuses do not have these) or an Allison automatic -- the latter of which was available for GM's Duramax and some larger gas engines -- most will have a badge on the driver's door. Any automatic with a lot of mountain use will need adequate cooling, especially a lighter-duty unit.
In your travels, there is something you should know if traveling cross-country -- Parking can be an issue across the country, regardless of the vehicle's size. Be aware of your height when driving through towns as well, most skoolies stand between 9 and 11 feet tall. One low bridge or a drive-thru can end your adventure in a hurry. Many localities restrict vehicles of certain sizes, weights heights, and lengths.
Be aware of this when parking for the night or passing through towns looking for food or other necessities. Wal-Marts are becoming a bit less welcoming to RVs and skoolies because of a few bad apples that leave trash and stay for weeks at a time.
You also have neighborhood busybodies that want to call on any such vehicle near their home, god forbid their precious property values drop.
In the interest of increasing your enjoyment of your adventure, I would get very familiar with a book called "The Next Exit". Chock full of exit ramps (I recommend the entrance side for safety) that are suitable for parking. Rest areas are also good. Lots of little hole-in-the-wall places you can find, even with a larger bus (just keep your size in mind for ingress / egress).
If you absolutely HAVE to park in a truck stop, I would advise you to avoid taking a space for a semi if at all possible, some are not very understanding about smaller vehicles taking their parking spaces. I have a few years driving such trucks, so I know about this. Most truck stops will have RV parking, and a mini bus can fit in most spaces that a cargo van could, length depending.
If you must park in a space meant for a semi, be aware that some spaces are meant for pulling through or backing in, others are only accessible by backing.
General rule of thumb, if you must use a space meant for a semi, be sure to park so that others can see the space is occupied. If it's a pull-through arrangement, put the rear of your skoolie at the rear of the space. If it's a space meant for backing in, put your skoolie's nose even with that of the trucks in that row. I've seen more than one RV badly damaged or totaled by a semi trailer in the dark because it was impossible to see.
Just a little courtesy to avoid a bad situation. I know I was a bit more understanding of such folks as long as I wasn't nearly hitting them because I didn't know they were there. But I would advise not to do it unless absolutely necessary. And try not to stay in such spaces longer than necessary.
All of this should be taken into consideration – and buying anything larger than a van-based minibus, I highly recommend a good basic CDL course (practice tests can be found on truckersreport.com
, and a Commercial Driver's Manual can be obtained at your local vehicle licensing agency).
Taking an actual course isn't required, as conversions are required to be titled as a motorhome, which exempts them from NEEDING a CDL, but it is still good knowledge to have. These things don't stop or turn well – ESPECIALLY the larger ones. Even the smaller ones you mention required a Class C with P/S endorsements as they were originally built and purposed. You will more than likely have to change some, if not all of your driving habits – so be aware of this.
IF you find a gas model that is Flex-Fuel, keep in mind that these engines CAN run on E85... But some of these have been known to get stuck in one mode or another when switching fuel mixtures, which usually mean a trip to the dealer. If they are NOT Flex-Fuel...do not run anything above E15 in '07+ models, and do not run anything above E10 in anything '06 and older. These engines are not designed for higher concentrations of ethanol and it WILL damage them.
A note about gasoline GM-based minibuses -- I'm sure most, if not all of these will have the 6.0L / 8.1L, but some smaller ones may have the 5.3, which has the Displacement-On-Demand setup. Be aware that this setup is known to malfunction and requires replacing valvetrain components. It's nice to have when it's right, but a real PITA when it's not. Aftermarket kits exist that completely eliminate this flunky system.
You would be well-advised to steer clear of hybrids and CNG and LPG-powered models, for lots of reasons. Hybrids are very specialized and not easily serviceable (if at all) by anywhere but a franchised manufacturer's dealer (where labor rates often exceed $120 per hour).
LPG is usually taxed for vehicular use, CNG is not readily available just anywhere, and the tanks must be certified and checked meticulously every so often. They are extremely costly to replace, and make the vehicle a veritable bomb -- Power and fuel range are terrible to boot. Unless you know someone who can easily convert the vehicle to diesel or gas, whichever applies, I would pass on such models. The only benefit is that the fuel burns clean, not enough to outweigh the obvious caveats.
For diesels, basic emissions began with Exhaust Gas Recirculation systems, and they were headache enough. Some lighter-duty models (such as the Detroit 6.2 / 6.5L) began using this as early as the 90s. Larger diesels did not get this sort of thing until around '02 or so.
Then Diesel Particulate Filters (diesel version of a catalytic converter) showed up around '02-'04, and they made things even more interesting... Don't take my word for it -- Google "Diesel Particulate Filter Fires" and click "Images" -- or better yet, if you know someone else with 18-wheeler experience, ask them how many trucks they've seen or heard of that spontaneously combusted and burned to the ground because of a DPF malfunction.
Diesel Exhaust Fluid arrived somewhere between '08 for some models, and that system is the devil's spawn, especially as it is used in conjunction with the previous two. These are the primary reasons I wouldn't buy a diesel newer than about an '02. Albeit, the MaxxForce engines in the newer generation of larger buses are really the problem children... Don't buy ANY bus with a MaxxForce, under ANY circumstances. The others haven't been as bad... apart from... *drum roll please*....
The '03+ 6.0 PowerStroke diesel -- avoid these like the plague, you do NOT want one of these either. The pre-'03 7.3 is a much better engine. The Caterpillar 3126 and C-7 have been known to have head gasket issues, though I'm not sure how common those issues are.
One caveat in considering a larger bus, think long and hard about whether you want a $1300 tow bill or a $3000 repair bill – heavy wreckers are $100 hookup and $10 / mile and most truck repair shops charge between $80-$125 an hour, some more.
Choose wisely, and maintenance is key -- an ounce of prevention is worth a pound of cure. One nice thing about a skoolie -- as long as it's converted well and the conversion does not hinder serviceability -- truck repair shops are much more welcoming of skoolies than conventional RVs, for a number of reasons.
That being said -- Many here will tell you that the right bus takes a bit of searching and time -- don't settle on the first one that looks nice and runs good. I'll give you a run-down of what I've observed in my time here (Round two - my previous account was deleted at well over 3000 posts) and my own real-world observations and experiences (mostly with trailer trucks, but I myself owned a Ford chassis Blue Bird back in the day).
Transmissions: 4L80E / 4L85E for GM, Fords (depending on year model) used AOD, AOD-E, 4R70W, 4R75, and newer ones are using the 5R110W. None are really that bad, but none of them are bulletproof, either. Transmission problems can be notably more expensive with Fords, because certain components are very vehicle specific -- the transmission being one such part -- making it difficult to source a good used one.
A note about these smaller buses -- Depending on their age -- GM's diesels will either be 6.2 / 6.5L Detroit diesels or 6.6L Duramax, each having their own nuances. Earlier 6.2s had head gasket and block issues, the 6.5L is turbocharged, the 6.2L is not. The 6.6L is known for fuel problems, particularly the injectors on the LB7s.
The Ford diesels are okay up to '02 -- the last year for the 7.3L. The 6.0L is a bus-sized headache you do not want - problems galore, as I stated previously. Unfortunately, a few of the bigger buses since '03 have gotten these too.
And be prepared to repair / replace brake linings and/or tires -- many buses being retired are on the verge of needing service in this area, which is oft-overlooked by folks new to the experience. With a larger bus, steer tires will likely be about $200-250 each, drive tires about the same. They are not cheap, even for smaller buses. Brakes on most trucks are about $2000 per axle, depending on the system and the shop. Smaller buses have more expensive brake service as well, as the parts are heavier-duty than a standard van. Sometimes you get lucky and the bus had these serviced / replaced not long before it was retired.
I'm sure there are members here that are more than willing to help you find a suitable candidate. Most of us long-timers here know good sources for finding good buses. GovDeals and PublicSurplus can be a source -- ABOVE ALL -- NEVER BUY SIGHT UNSEEN, INSPECT IN PERSON IF POSSIBLE, OR AT LEAST HAVE SOMEONE EXPERIENCED AND LOCAL TO THE VEHICLE TO INSPECT IT FOR YOU.
Lots of good folks here with a lot of helpful advice, some are even willing to help find the right bus.
I think some members here might not mind checking one out for you if it is somewhat local to them -- an experienced truck or bus mechanic is best, however. A hundred bucks to a reputable diesel mechanic could save you the hassle of paying $1800 for a bus that turns into a hefty tow and repair bill -- if you don't wind up scrapping it -- which has happened before. Just know that ANY of them can break down on the way home. Most won't -- but it's not unheard of.
Prime example -- I bought a retired police car once on PublicSurplus from Roanoke County, VA without inspecting it on their listing of "Runs Good - Turned In For Newer Vehicle" and it turned out most of the #3 rod bearing was laying in the oil pan. It got home, but it definitely needed an engine badly. Don't let that scare you off, just learn from my mistake of buying sight unseen.
And I wouldn't buy buses from the northern part of the country unless you're willing to contend with a lot of rust -- a far more serious problem than you might think. Just ask around the site about that one. Lots of these things hide rust in places you won't notice it until you've already bought it.
If perusing dealers, DON'T EVEN THINK ABOUT FLORIDA CHURCH BUS. They burned a former member here BADLY, a story I am very familiar with, as they told other potential buyers a great many untruths about the transaction and their response to the problems that ensued. Be sure to ask questions here about ANY 'dealer' you're thinking of buying from. 99% of the buses you find will carry a 'tail light' warranty, meaning the warranty expires when they lose sight of your tail lights as you're driving away.
Most auctions and dealers will not / cannot allow you to drive your new purchase home without removing seats / stop sign arm, 'SCHOOL BUS" and municipality lettering if not already done. Some states even require that it be repainted something other than the school bus yellow. Activity buses and prison buses will be exempt from this, as they are not so equipped.
Another potential snag is that most can not allow it to be driven off their lot without a CDL, either. I am one of a few members here who holds a CDL, albeit I have a Class A with only air brake endorsements -- small van-based buses require a Class C minimum, larger ones a Class B with P endorsement for transport until it is registered and titled as a motorhome, if not already done.
There are a few of us here who hold a CDL, I am one that may be willing to help with moving your new purchase. Be aware, I have a Class A, not a Class B, and do not have passenger endorsements, but other members here have noted that IF they were stopped, the officer was usually understanding of the situation. My having a Class A CDL would likely greatly increase the chances of that, as long as I had proof I was relocating it for a new owner. (Class A is for larger, heavier vehicles that require more skill to maneuver, but the P/S endorsements generally don't apply to it)
For their bigger brothers:
Engines: Caterpillar 3208, Navistar DT466, DT360, T444 / T444E, Cummins 5.9 / 8.3, Ford 7.3 (essentially a T444 with a few differences, from what I gather from others, who can chime in if I've missed any gems), are all good engine choices to start with in the diesel department. Gas engines are not as common as they used to be, but most generally are not a problem.
In fact, the emissions equipment woes of newer diesels have caused some districts to start ordering gas models again after about 25 years. I would absolutely not buy any diesel newer than an '02, due to emissions issues, as they are somewhat expensive to fix when they decide they need attention. '02-'04s may not be AS bad, but '04+ can be a real pain (and expensive) when they need attention (and they will).
The 6.6L Ford / New Holland diesel is a good engine in its own right, but relatively gutless, and being a tractor engine in actuality, will prove difficult to find parts for if necessary. These are made in Brazil, hence they are known as the "Brazilian" diesel.
Transmissions: Manuals are best, but getting harder to find. Automatics: Most candidates you find will have one of these: Allison AT545, MT643, 2000, MD6030. The AT545 is very basic, and somewhat weak. Not a TERRIBLE transmission under normal use, but most need major attention when they are retired. The MT643 is a good bit better, 2000 is a good one as well from my understanding, and well, the MD6030 is a gem if you can find one. Some auto transmissions will have a bit of an Easter egg in the form of an extra gear that can be unlocked if it's not already set up -- just have to know the right person with the right equipment to do it. I'm thinking this applies to the MT643, 2000, AND the MD6030. Smaller van-based buses will not have these, they will have whatever normally comes in the van chassis they are based on.
Brakes: Air or hydraulic? Tough question, and depends on some of the following scenarios... But if your plans include mountains or a lot of hills, I would opt for air. Though the inexperienced should not attempt servicing them, they're not as complicated as most think, and hydraulic brakes can fade quickly with mountains or lots of hills, a very dangerous situation giving a point towards air brakes.
A manual transmission will help a lot in such a situation, but they are getting harder to find. Engine brakes are almost unheard-of with skoolies, but if considering a larger one, this would be a nice selling point if the chassis and engine / trans setup are desirable.
Otherwise, hydraulic will be fine, but I would avoid late-model Fords over 2-ton (B600+ / F600+ / E550+) with hydraulic brakes -- the system those use is highly expensive to repair and maintain, and most shops won't even touch them -- that's assuming you can find parts without selling your first-born to buy them.
The van-based minibuses are usually okay in this department, they did not generally offer air brakes, but from a mechanical standpoint are largely no different than a standard cargo van of the same body line and will not have this system. Some NaviStars (Internationals) with hydraulic may or may not have this system as well, I believe it went the way of the do-do around 1997-1999.
Lucas-Girling is the name of the manufacturer of the system I mentioned here. More or less, some crackpot engineer tried to merge operation characteristics of air brakes into a hydraulic system -- and when it worked as intended, it was good. But when it failed --- OH BOY. If the parking brake is a little metal box with a plastic toggle switch or anything similar, RUN. I had to junk an otherwise perfectly good 64-passenger Blue Bird on Ford chassis with a strong 429 and manual trans because of that system.
All this aside, If you want a bigger bus... Your body choices include conventional (dog-nose), and flat nose. Flat-nose are a bit easier to maneuver in most cases, but come in two flavors -- front engine and rear engine (also called RE or pushers). Front-engine buses will tend to be a bit hot and noisy to drive, especially on the highway. Pushers are quieter and cooler in the front when driving, and will generally have better drive traction in bad weather, but have their own special concerns with cooling at times, particularly with hills or mountains.
As I said earlier, consider carefully what your planned use is once your conversion is finished. Will you be traveling cross-country? Back roads? Mountains? All of these merit consideration. If you're simply going to park it on a lot and live in it, most anything will do -- but otherwise, you have to consider this to choose an optimum setup... Major mechanical changes such as rear differential gears and transmission upgrades are costly and time consuming, which take away from your enjoyment. You'll be much happier on all fronts just taking your time to pick the right bus for your conversion.
Occasional jaunts with no highway cruising, chances are a DT360, 7.3, T444/E, or 5.9 Cummins with an AT545 will be just fine as long as you're okay with 55-60 mph cruising -- standard axle gears in the 4.56-5.29 range will do just fine for this.
If you're planning highway cruising, you'll really want the MT643 at the minimum -- the 6030 is much better, and you'll want an axle gear more in the 4.11-4.56 range, I'd say.
If your adventures are meant to include mountains, you'll want the Caterpillar 3208 turbo, DT466, 8.3 Cummins, 7.3 Ford, the MD6030, and axle gears in the 4.56-4.88 range.
Just my $0.02 here, I'm sure others may voice agreement or dissent. But that is what I would look for, I think most here will agree when taking into account my stated experience and observations.
In my experience driving semis over-the-road, Freightliners with Detroit power were the most reliable. Personally, in my dream world, larger skoolies would have been getting Detroit's DD5 and DD8 as engine options the moment they were available in medium duty trucks, and 5 /6 speed manuals or a slightly different version of Detroit's DT12 automatic. Alas, the bus builders are only now starting to use Detroit power, after a 25-year hiatus, and as far as I know, the MD6030 is still the best automatic you can get in a skoolie.
Remember, all I've said here is purely in the interest of increasing your enjoyment of your purchase, and the finished product, as well as, above all, safety. Remember, a school bus as it was built was and still is a commercial vehicle, even once it's been gutted and registered as a motorhome -- it is simply exempt from CDL requirements. Gutting it and making it into an RV does not change the fact that it weighs 12,000 lbs empty and has the mechanicals of a basic commercial truck. It only means you no longer need a CDL to drive it because it is no longer considered commercial use. As I stated earlier, it is still good to have knowledge of operating such vehicles.
That being said, welcome to the skoolie family, and I hope your journey is a safe and enjoyable one. None of this is meant to dissuade or deter you in any way, it is meant to help you understand what you are getting into. I think there are some out there with a poor opinion of the skoolie experience, that tainted their own experience with poor choices. As I said, choose wisely.