How many miles is too many miles on a bus

Mesuds

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I've been thinking about getting a bus to convert, and all the ones I've looked at seem to have alot of miles. If I do this I plan to be doing ALOT of driving. I normally wouldn't buy a car with more than 160,000 on it should I think differently about a bus? Anyway if you guys could let me know what you think I would appreciate it thank!
 
I've been thinking about getting a bus to convert, and all the ones I've looked at seem to have alot of miles. If I do this I plan to be doing ALOT of driving. I normally wouldn't buy a car with more than 160,000 on it should I think differently about a bus? Anyway if you guys could let me know what you think I would appreciate it thank!

160000 is low mileage on a bus, and it works against the bus. I'll explain.

We are talking about engines and transmissions that have an average expected life before rebuild ob between 350 and 500 thousand miles. These mileages are commonly achieved by medium-duty trucks running the same drive-trains.

In that context, 160k is barely broken-in. However, it's not that simple. Medium duty truck run all day, most days. They get up to operating temperature, and they stay there. School buses do not do that. They often run between 2 and 4 hours a day on multiple pick-up routes, and for only 180 days a year. The rest of the time they are parked. I think the average school bus does about 15000 miles a year under what the engine manufacturers would consider to be severe duty conditions.

That's going to shorten the life before rebuild, but it will depend a lot on how well they were maintained. In general, the bigger school districts will have more comprehensive maintenance programs, but that's not always the case.

If you buy a bus that was used mainly for activities, rather than running a regular route, then it is likely to have operated under better conditions, and have been treated better because they were generally expensive buses.

Bottom line here is that 160k, as mileage, is absolutely nothing to worry about, especially if the engine hour meter agrees (It should be under about 7000 hours on that mileage).

So to be sure all you can do is check ... Oil analysis, engine blow-by, smoke when warm, etc. Most school districts are honest about these things, but not all.

It's unlikely that a 160k bus will pose any real problems, especially if it is being sold because it has aged out of the fleet, but it's a bus, with an engine, and they can break.
 
I've been thinking about getting a bus to convert, and all the ones I've looked at seem to have alot of miles. If I do this I plan to be doing ALOT of driving. I normally wouldn't buy a car with more than 160,000 on it should I think differently about a bus? Anyway if you guys could let me know what you think I would appreciate it thank!

They all don't have a lot of miles necessarily. Mine has 26,000 miles, but was a bookmobile. Someone on the Board here has something redonkulous like 16K mi.

I saw a few full sized FE buses by me under $4K and 80K mi and 130K mi, IRC.

So, if low miles is important to you- go find your Unicorn.

Most important thing : It was driven and maintained regularly. Not always the case with Church buses.
 
Thanks I don't know how important it is to me persay I just don't want to be fixing stuff all the time little stuff is fine, but not interested in a $3000 dollar vechile I have to put $2000 of repairs into every year. I'm also interested in doing the veggie oil thing.
 
A straight mechanical diesel bus would be the way to go, and that would be older -- if want to do veggie. A higher mileage engine might not be a bad thing because you might waste the engine trying to figure it out any way. Most like the dt 466 engine. Stay away from cats. A pancake 6-71 in a Crown, I think, would be a great bus to play with. A 10 wheel Crown goes for $4 to 6 thousand.
 
Thanks What do you think about 5.9 Cummins I kind of like how common it is I figure lots of parts and mechanic should be able to work on it
 
Thanks What do you think about 5.9 Cummins I kind of like how common it is I figure lots of parts and mechanic should be able to work on it

That 5.9 depends upon the size and weight of the bus in question. If you have a shorty, and plan to have her as a weekend get-away camping bus, not a bad choice. However, if you're looking at a 40' full-time plan-to-see-all-of-North-America bus, then pass. That engine is too small for your needs. If you're looking for a summer vacation going to the Rockies - again, pass. The 5.9 is okay for a smaller bus with less weight. However, for a larger bus and driving in hills or mountains, the 5.9 will bog down to 10 to 20 m.p.h. depending upon circumstances.

As far as parts availability, your spot-on. Most Dodge/Freightliner dealerships and shade-tree mechanics know these engines well. Just keep in mind what you're looking to do with the bus before determining what size drivetrain you need, then search appropriately.

M :biggrin:
 
So what’s a good engine size for the full time see all bus. I’m looking for a bus but don’t even know where to begin. Can someone put together a top 5 things to look for list maybe if possible. Thanks


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Keep in mind not all engines are designed to have the same lifespan, so the same mileage on two different buses can mean different things. The diesels in Skoolies are certainly designed to last longer than an automotive engine, but are not quite the "million mile" engines used in long haul trucks. Some of the engines are designed to last longer than others.

One of the ways to gauge the relative design service life of different engines is to look at the B10/B50 ratings from the manufacturers. This is not a predictor of actual life span of an individual engine, but gives a somewhat fair comparison of different engines from a statistical perspective under controlled conditions. B10 means that 10% of the engines within the sample pool required a major overhaul by that mileage, B50 means half did or the average mileage to major overhaul. A "good" engine with excellent maintenance and gentle use could go much longer. A "bad" engine that's been abused could go much sooner.

This data is not always easy to find, but here is what I managed to dig up after hunting a while back.

Code:
[FONT="Courier New"]Engine               B10 / B50
International VT365    - / 300k
International T444e 200k / 350k
Cummins ISB / 5.9L  200k / 350k
Cat C7                 - / 400k
Mercedes 906           - / 500k
Internation DT466   300k / 500k
Cummins ISC / 8.3L     - / 500k
Detroit DD13           - / 1,000k
Volvo D13              - / 1,200k[/FONT]

In most cases these engines are designed to be rebuilt and "do it again" so long as you don't wait too long and experience a catastrophic failure. I believe this info also only applies to the core systems of the engine, many ancillary systems are likely expected to be replaced / rebuilt more frequently. But failure of those systems (cooling for example) can cause major damage and/or shorten engine lifespan.

Rob
 
I'm also interested in doing the veggie oil thing.

Ok, so that is decision that needs to be made now. Some tolerate it, some don't. I don't hear many veggie Cummins tales.

7.3 IDI engine or any all-mechanical (older) will be best bet. Newer engines will not be as happy unless labeled b20 $$$ and that's only 20%.

Read
 
So what’s a good engine size for the full time see all bus. I’m looking for a bus but don’t even know where to begin. Can someone put together a top 5 things to look for list maybe if possible. Thanks


Sent from my iPhone using Tapatalk

After owning one REALLY underpowered bus, two buses with merely adequate power, and one with HIGH HP, I'm now a true believer in having a large, powerful engine. If the bus isn't to be driven much at all, then anything will do.
But I like to drive my buses, and I don't personally want any bus that doesn't have a DT466 or a Cummins 8.3 ever again. A good, powerful bus is worth looking high and low for, imo.
But everyone's needs aren't the same.
A decent 444E with more than 175 hp and transmission with lockup is probably enough engine for 80% of the folks converting buses out there.
 
For most of us it's usually about the following;

1. Alway look for rust first, undercarriage and body.
If there is visible rust there is also lots of rust you can't see.

2. Engine; the strong preference here is cummins or internatinal, bigger is better
There are numerous types of engines that will do the same job. These two are generally thought to be less expensive to operate and maintain.

3. Diesel, not gas. Good mileage in these vehicles comes from a diesel engine. Older gas parts are becoming difficult to find.

4. Air brakes, not hydraulic. Air is considered more dependable and safer.

5. Tires; look for good tires so you don't have to drop $2k + or - just to drive it.

Above all, be picky. Very picky. Get what you want, don't settle. If you don't know what you want, start frequenting bus sales and start learning what you do like.

Your choices should be specifically dependant on what you want to use the bus for.
 
I don't personally want any bus that doesn't have a DT466 or a Cummins 8.3 ever again. A good, powerful bus is worth looking high and low for, imo.
But everyone's needs aren't the same.

Good advice!

I also have driven under powered buses. It can be ok for a while but in time it sucks the fun out of driving.

If you can find a bus with the DT466, DT530 or Cummins 8.3 you will be better served.

As far as the transmission goes, look hard for an MD3060 or 2000 series.

Another consideration, if you find a DT or 8.3 & MD3060 equipped bus, is who built the body. Those with Thomas buses have had good success getting 6th gear unlocked on their MD3060. Us Bluebird owners have not had that level of success. It is a manufacturer policy thing. I love my Bluebird but if I had it to do again I would have an eye towards Thomas as well.

Good luck.
 
Good advice!

I also have driven under powered buses. It can be ok for a while but in time it sucks the fun out of driving.

If you can find a bus with the DT466, DT530 or Cummins 8.3 you will be better served.

As far as the transmission goes, look hard for an MD3060 or 2000 series.

Another consideration, if you find a DT or 8.3 & MD3060 equipped bus, is who built the body. Those with Thomas buses have had good success getting 6th gear unlocked on their MD3060. Us Bluebird owners have not had that level of success. It is a manufacturer policy thing. I love my Bluebird but if I had it to do again I would have an eye towards Thomas as well.

Good luck.

I think it has a lot to do with the FD ratio. I'm guessing neither Thomas nor Blue Bird want any part in creating 90 mph buses.

With my FD ratio of 5.38 I expect no trouble from Thomas. Speed in 6th at the rev limit would be 80 mph.
 
I think it has a lot to do with the FD ratio. I'm guessing neither Thomas nor Blue Bird want any part in creating 90 mph buses.

With my FD ratio of 5.38 I expect no trouble from Thomas. Speed in 6th at the rev limit would be 80 mph.

Buses running routes can do 85 mph, it all depends on the bus.





 
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Okay, but if my FD ratio were 4.44 (common), top speed in 6th would be 95 mph.

I'm thinking that Thomas would say "No".
 
I'd go with your earlier FD ratio, just to be on the safe side.

Thomas already told me they fitted a 5.38. They won't accept any BS from me about a lower gear in there, without proof.

A friend had his unlocked with a 6.14 ratio. My 5.38 won't allow me to exceed the speed rating of the tires, so I am confident.
 
Okay, but if my FD ratio were 4.44 (common), top speed in 6th would be 95 mph.

I'm thinking that Thomas would say "No".

If you were a school district ordering a million dollars worth of buses they would build you whatever you wanted, within FEDERAL spec. AFAIK there's no federal cap on speed for school buses. That seems to be regional.
But Thomas AND Bluebird both have built and sold buses for schools that would exceed 80 mph.
 
If you were a school district ordering a million dollars worth of buses they would build you whatever you wanted, within FEDERAL spec. AFAIK there's no federal cap on speed for school buses. That seems to be regional.
But Thomas AND Bluebird both have built and sold buses for schools that would exceed 80 mph.

So Thomas should be okay with my request.

I'm not wanting to drive at 80 mph, I want low rev, highway cruising at 65 ish.
 

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