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Author Topic: Best bus for conversion?  (Read 50943 times)


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Best bus for conversion?
« on: August 29, 2009, 12:38:59 PM »
We're looking at doing a bus conversion and were wondering which bus is best for this?  We're very new to this and have looked at school busses, blue bird busses, and MCI busses.  But we are very lost.  Please help!
Ria, Big D, Autie, Izzy
In the Orange F550 Beast
Still looking for the right 5er


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Re: Best bus for conversion?
« Reply #1 on: September 01, 2009, 04:03:08 PM »
When Jack and I were considering doing a bus conversion(years ago), we thought that an MCI or a Prevost would be the best choice. However, after thinking over what a HUGE and EXPENSIVE project a conversion would be, I vetoed the idea.

We bought a 1993 Bluebird Wanderlodge motorhome in 2004. We are happy with it.

Google bus conversions and you will find appropriate websites. Good luck.

Jack and Liz Pearce and Oreo the Escape Cat
Fulltiming in a 1993 Wanderlodge WB 40 ft
Dhanis, TX - Winter
Buena Vista, CO - Summer


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Re: Best bus for conversion?
« Reply #2 on: September 01, 2009, 07:24:15 PM »
The choice of a bus to convert will be a very personal choice, depending on many factors that only you can decide upon.

The typical "coach" type bus (GMC, MCI, etc) typically come in 96" and 102" widths, have a rear diesel engine with a lot of power, usually have the interior floor above the level of the wheels, and most often have a steel frame with aluminum skin.  Often the front and rear cap are fiberglass.  They are also the more "typical" type of bus conversion, and are usually easier to get pushed through the paperwork offices in your state (title, insurance, tags, etc).  Coach style busses are often 24 volt dc systems.

A school bus has many variations to consider.  You have gasoline and diesel power plants, with front, mid, and rear engine placements.  Typically, the school bus is 96" wide, and an all steel construction.  School busses are designed to carry their full weight on the roof and survive rollover type accidents better than most other types of vehicles.  You will see 3 basic body styles, those being the conventional or "dog nose" type, the flat nose type, and the "twinkie" type made primarily by Crown, but I think Gillig also made some.  The conventional nose body style is always a front engine design, and the easiest type to find with a gas engine.  The flat nose aka forward control models have the driver sitting forward of the front wheels, and comes in both a front and rear engine design.  These are almost always diesel engines (especially the rear engine ones), but sometimes you can find a gasoline one.  The Crown and Gillig busses tend to be either a mid engine or a rear engine, depending on the year.  School busses are often 12 volt dc systems.

Transit busses don't really fit either category.  These busses typically have a higher floor like coach busses.  They are most often rear engine diesel busses, but there are variations to that.  These can be either 12 volt or 24 volt.

Tour busses are mostly the same as coach busses.

Short busses are available in school bus varieties, transit bus varieties, and even tour bus varieties.  Most often these are built off of a van chassis, or a small work truck chassis such as the venerable P30 (bread truck style) chassis.  Short busses are almost always 12 volt dc systems.

Length is a primary factor to consider.  The largest variety of lengths seems to be in the school bus marketplace.  A general rule of thumb for school busses is to count windows and multiply by 25 inches.  That will get you close.

Engine location is a primary factor to consider.  A rear engine diesel bus drives usually drives like a dream, and has all the engine heat and noise far from the driver, which is nice on a long run.  I've not got any experience with a mid engine bus.  A front engine bus typically will drive like a large farm truck.  The short busses often drive like a small work truck, or oversized pickup truck.  A rear engine bus gives more room underneath for storage due to the lack of a driveshaft running from the front to the rear.  A mid engine bus loses a lot of underneath storage space due to both the engine and the driveshaft.

Under body storage is something to consider as well.  A coach/tour style bus often has pre-built storage under the floor, and often it goes all the way across.  This is really nice, as it gives you plenty of room for tanks, etc.  Some school busses (usually activity busses) also come with basement storage compartments, although they tend to not be as tall as a tour bus storage bay due to the floor being lower.

Width is something to think about.  A 96" wide school bus ends up with about 89" or 90" of interior wall to wall space as an example.  Different busses will measure out differently.  It is difficult to stretch the width of a bus.

Height is a very important consideration.  A school bus will typically be approx. 10 feet tall outside.  This translates to 5'9" up to 6'6" of interior height, depending on the model and design of the school bus.  I don't know what the interior height of a coach or tour bus would be.  One thing many people do as part of a bus conversion is a roof raise.  For a coach type bus, often there are places where new front and rear endcaps can be purchased, and a lot of information exists on raising those roofs.  For a school bus, with its all steel construction, you would end up doing your own fabrication solution for the front and rear.  Many school busses have had the roof raised.

Cost is always an issue to consider.  A school bus can be had for $500 to $5000 and be an excellent platform for a conversion.  A similar good starting point for a coach will be $5000 to $15000.

Gross weight is another thing to consider.  Many conventional RVs are built really close to their limits (especially the budget models), leaving very little if any room for cargo.  Busses tend to have very high weight ratings.  A typical conversion doesn't add as much weight as you might think, typically leaving a lot more room for cargo and still be safe.

You will also need to think about whether you want air brakes or hydraulic brakes.  Air brakes are quite common on coach and transit busses.  School busses can go either way, primarily depending on the GVWR.  There are also air over hydraulic systems that confuse me to no end.

These are the things I can think of right off the top that you should consider.

When I went through this process, I ended up deciding on a school bus for my conversion.  The primary reasons were the cost and the safety factor and the weight capacity.  I found a rear engine flat nose diesel bus that is approximately 39' long for a bit under $2,500, and it drives really nicely.  Most of the rest of what I have to say is school bus specific, as that is all I have direct experience with.

Engine:  Most of the engines in school busses tend to be considered good.  The Cummins 6BT 5.9L (a variant of which is used in Dodge RAM pickups) is very popular.  The Cat 3208 comes in turbo and non turbo models.  If you have the option, I recommend the turbo no matter which engine you get.  The Navistar T444E (similar to the powerstroke 7.3L engine I believe) is also well liked.  The 8.3L Cummins is the engine I would have liked to have gotten.  The gasoline engines in busses tend to get the job done, but get about 5mpg on average.  Some are a little better, some are a little worse.  My 3208 averaged 8.75 mpg on a 600 mile trip.

Transmission: You need to decide if you want a manual or automatic.  In the automatics, Allison is considered the king.  In order of least preferred to most preferred there is the AT545, MT643, MT644, and MD3000 series (MD3060 is most common).  The AT545 doesn't have a lockup torque converter, so you always have some slippage between the engine and the transmission.  I was concerned that it would be an issue when trying to use the engine for braking going down mountains, so I made sure to get the MT643.  The MT64x and MD3000 series do have lockup torque converters.  The MD3000 series I believe are electronically controlled.  I don't know much about those.  I think the MT643 and MT644 are very similar.  On the manual transmission side, there are several options, and all are considered good.  If you do get a manual, more gears tends to be better, and a 2 speed rear end tends to be better.

Tires:  Always check the date code on the tires.  This is an important thing to learn about, and this forum has been very helpful with educating everyone on this fact.  Watch out for tires over 5 years old.  Also, before buying, get the tire sizes and call around to various tire shops to see how difficult they are to source.  Some odd sizes exist out there and are difficult to find.

Gearing:  This is something that is often overlooked.  City busses tend to be geared for city driving, and often will tear the engine apart at 60mph if you can even get them to go over 45mph.  You will run into this with any kind of bus, so it pays to pay attention.  Driving cross country at 45mph with the engine redlined would not be pleasant.  On the other hand, apparently it isn't ridiculously expensive to get a good truck shop to change the gearing for you, so if you found a really sweet deal on a city geared bus, it might still be worthwhile.

Storage:  The more storage that is already present in/under your bus when you buy it, the less you have to build.  On the other hand, it might not be where you would prefer it to be.  Again, it is a tradeoff.

Doors:  Conventional style school busses have 2 doors, one at the front by the driver, and one in the rear.  Rear ending school busses move the rear door to the side, usually the street side somewhere between the middle and the back  Coach style busses tend to only have the one front door.  Transit busses often have 2 doors on the curb side.  Some transit and school busses also have a handicap/wheelchair lift.  This could be beneficial, or just be in the way.  These are usually wider than normal doors and the lift is usually hydraulically operated via electric power.

In my case, I ended up with a diesel pusher, approx. 39' long, air brakes, MT643 transmission, with a Cat 3208 non turbo 210HP motor for my conversion.  I paid about $2500 for it.  I love the way it drives, and the way it always cranks up without issue.  Unfortunately, between the time of buying it and the time of starting on my conversion, it filled up with junk that didn't even belong to me.  Eventually, I bought a second school bus to be a moving shed to put all the junk in, and also to hold all my conversion supplies while I worked on the pusher.  The shed bus (named The StowAway) is a chevy C60 truck chassis with a thomas body, conventional nose, front engine gasser with a gm 366ci fuel injected engine.  It gets terrible mileage.  It has a 5 speed manual which is really a 4 speed with a granny gear.  It is governed at 55mph.  It cost me $1400, and was worth every penny.  The diesel pusher is named 'unleashed' and is a freightliner chassis with thomas body.

My gas bus weighs 13,960 pounds empty (with seats removed), and has a GVWR of 25,580 pounds, leaving 11,620 pounds for a conversion and cargo should I want to convert it.  My diesel has a GVWR of 33,280 pounds, and I don't know the empty weight yet, as I plan to pull up the floor before weighing it.  I expect it to weigh in around 18,000 to 20,000 pounds empty.

There is a lot more information out there, and probably more that I know that would be helpful to you, but I'm running out of things to think of.  There is a school bus conversion site at http://www.skoolie.net/ with friendly people.  There is also a bus nuts online site that I misplaced the address to that focuses on coach style busses, and they're also very friendly and helpful.  You should also look at truck conversions out there for ideas, as it all helps.  Another source for ideas is the marine world.  Anything built to survive a marine environment will think an rv environment is easy. 

If you have any specific questions, feel free to ask, and I'll try my best to help you find an answer.

Also, Jack and Liz sent me a lot of links when I first started looking for my bus, and there was a lot of helpful information in those links.  They make an excellent point that buying a ready to go wanderlodge is a great investment.  Wanderlodge is basically Bluebird's conversion of a school bus/transit bus chassis into an RV, and it stands the test of time.  The resale value of a wanderlodge is good.  They are also relatively easy to renovate, especially compared to budget minded RVs.  I estimate that by the time I finish my conversion, I'll have as much money tied up in it as a good used wanderlodge would have cost me.  On the other hand, it'll be built exactly as I wish it to be.  And there's something to be said about that too.  :)

I hope this information is helpful,


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Re: Best bus for conversion?
« Reply #3 on: September 25, 2009, 12:42:05 PM »
I just saw this topic. I could comment about ours, but it would be a very long post. We have have a 45' MCI (which are very rare converted because they are still in service as a seated coach, and are expensive) DL3. If you are serious about getting a bus, I would go over to the guys who know about them. Bus conversion board. We will be able to help you out over there.

There is no doubt that with a conversion you get it your way. Another plus is that with a bus, they are far more sturdy then your average Class A, whatever.

So yes there is a lot of options.

God bless,



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Re: Best bus for conversion?
« Reply #4 on: October 05, 2009, 05:00:42 PM »
Jim, where are you? We have all been waiting with bated breadth for the next installment.

What's up with your project?

carson FL
 West Central Florida
Ex RV'er. (1995 Winnebago Adventurer)
2007 Buick Rendezvous, SUV / CROSSOVER

...Logic works like a charm...