How many miles is too many?

[glenncooper]

This is one of those questions where a straight answer seems elusive. And it’s a question that I want to ask of any decent Diesel engine - not just the internationals.

So how many miles is too many? I recently walked away from a really interesting little bus that had 267K on a DT360. That’s not big mileage in the truck world, but I realize that a route bus has an entirely different life than most medium duty trucks. In this case I didn’t know the engine hours, which I realize is a big factor.

My thinking also goes like this: I see many late model busses being auction off when they are in the 200’s. I don’t really see many busses in the 300’s. I’d rather hold off for a bus in the low 100’s with a clean history and pay a bit more for it.

Once I get a bus and convert it I also plan on putting on some miles, so having some life left is important.

Thoughts?

[o1marc]

All depends on the maintenance the bus has seen. I believe these motors, if well maintained can see up to 500k before needing rebuild. Schools know how many miles they can run before it starts costing money to maintain, then they dump them, usually between 150-250k miles, or around 12-15 years. Maintenance records are a help to know if and when the motor in it now was ever rebuilt.

[djdalfaro]

Another thing to consider is how much money/time it will take to get your motor to a "like new" or rebuilt condition. If it only costs 2-3k to have it completely rebuilt, regardless of what the odometer says, the motor will run like a fresh baby. Of course the motor is not the only piece of equipment that needs preventative maintenance.

This is the main reason I've chosen a mechanical engine that doesn't have any of those magical electronic elves in it. No computer to hook up, and all the maintenance can be done in any decent shop or at home with the right tools.

The International engines appear to be the best in this regard as they are wet sleeve. I believe the 8.3 Cummins is also a sleeved engine so that is also an option. The 5.9 Cummins is a bored engine which means the cylinder is bored into the block. This means the rebuild will be more expensive as the block needs to be pulled and machined to be rebuilt. However, the 5.9 is a VERY common engine in the light duty world so there are countless parts available and shops willing to do the work.

Another option if you are worried about the high mileage is to consider the cost of a replacement engine into your offering price. If you can get a rebuilt or low mileage engine/short block for 1k, and the bus you are looking at is higher mileage, offer less and put away funds for that rainy day. Heck just wait til you find a good deal on an engine, and store it until it's needed.

[glenncooper]

Thanks for your feedback. I had been working under the belief that an engine rebuild was more like $10K, which affects my thinking greatly. If it's 10K then that's a big factor to consider, but if its $2K to $3K that's no big deal. Thanks again for your input.

[djdalfaro]

Originally Posted by glenncooper

Thanks for your feedback. I had been working under the belief that an engine rebuild was more like $10K, which affects my thinking greatly. If it's 10K then that's a big factor to consider, but if its $2K to $3K that's no big deal. Thanks again for your input.

You should get a quote if you are looking at a specific engine. I say 2-3k as I can do most of the work myself. A rebuild kit will cost somewhere in the neighborhood of 1-1.5k on an international. I'm not sure on other engines. In other words, DON'T TAKE MY WORD ON IT!!!

[brokedown]

All great info in here. I can say that my perspective is that while these engines are absolutely built with durability and longevity in mind, school bus routes are considered extreme duty use. It's a lot easier to hold highway speed and add a mile per minute than it is to stop and go every 1000 feet and rackup 10 miles in 4 hours.

Personally, both my buses were under 180k when I bought them. I'd probably go as high as 250k for a bus that was obviously well maintained, but above that the little voice in my head would start scolding me.

Rebuilding the engine on a bus isn't the worst thing in the world, but it's not a great place to start. I see people buying buses with 300k+ on them and not a lot of real horror stories but at that level I'd be looking for an overhaul in the maintenance records!

If I saw a bus that was reasonably worth 10k (we're talking like an All American with the 8.3 and a 6 speed transmission and lots of under carriage storage and highway gearing and brand new tires and no rust and cruise control and serious air conditioning and a bag with $1000 on the floor) for 4k that needed an overhaul, I'd consider it. My new bus with less interesting stats cost a lot less.

[glenncooper]

I appreciate your feedback! You've echoed my big concerns that 270K miles on the engine of a route bus is NOTHING like 270K miles on a most medium duty trucks that do a decent amount of mileage on faster roads or highways.

[family wagon]

Originally Posted by djdalfaro

You should get a quote if you are looking at a specific engine. I say 2-3k as I can do most of the work myself. A rebuild kit will cost somewhere in the neighborhood of 1-1.5k on an international. I'm not sure on other engines. In other words, DON'T TAKE MY WORD ON IT!!!

I can tell you that I'm in almost $300 in parts just to put a new head gasket, head bolts, and one push rod into a Cummins 8.3. The answer depends on what all one considers to be part of rebuilding a whole engine (crank bearings and seals, piston rings, cylinder sleeves, oil & water pumps, maybe some valves, guides, and springs, who knows what else). I wouldn't be surprised to pay US$2k-3k just for parts on an extensive rebuild, plus maybe a man-week of shop labor if I'm not doing it myself.

I'm not sure what to expect for heavy diesel shop rate, but 4 years ago when my injection control valve died, they wanted US$1200 for a re-man replacement and about that much again for labor to install it. I did the job myself, moving very slowly, in under 6 hours. A mechanic who knew what he's doing might have done it in 3-4 hours.

As for mileage: "too much" might depend in part on how much driving you want to do. I'll be surprised if I put 20k miles on my bus, so at its current mileage of 287k, I only need to get 10% more than what it has already given in its life. In other words even if it's very nearly used up there's a good chance I'll get what I need out of it.

[glenncooper]

Thanks for your reply. Once I get a bus and convert it I intend to drive the crap out of it - all over everywhere (yes, understanding these aren't the most comfortable vehicles for putting big mileage on...). I'd like to think I can put another 100K on whatever I get. I'm not in a place to do the work myself (either physically or in terms of skills) so I'll be tied to a shop for this work. I'm guessing that for many of these engines that it's probably in the range of $6K to $10K if I have someone rebuild it...

[EastCoastCB]

Originally Posted by glenncooper

Thanks for your feedback. I had been working under the belief that an engine rebuild was more like $10K, which affects my thinking greatly. If it's 10K then that's a big factor to consider, but if its $2K to $3K that's no big deal. Thanks again for your input.

Depends. YOU can rebuild your engine for 3 grand.
A shop is gonna charge you 3x that. A dealer will charge you 6x that. Maybe even more.
My timing cover is toast and the dealer wanted $9300. That's not even a rebuild. That's just the front covers.

[JDOnTheGo]

Originally Posted by glenncooper

This is one of those questions where a straight answer seems elusive.

That's because it is impossible to answer. Sorry... I know nobody wants to hear that.

New things fail and used things fail. Sometimes the difference is maintenance, sometimes not. It is impossible to know how these engines have been operated or how well they have been cared for (even if you have logs, they may not be accurate nor tell the whole story). It is a gamble. About the only thing you can do, if really worried about it, is have a qualified person take a very close look and that is absolutely no guarantee of anything.

My coach had eleven hundred thousand miles on it. Still going strong. I don't know if that is with the original engine or if there was a rebuild or two somewhere in between. Will it fail tomorrow? Maybe. Will it keep running well past me? Maybe.

Some will say an engine with high mileage (and in good overall condition) is likely to continue running for a very long time.

[o1marc]

Originally Posted by JDOnTheGo

That's because it is impossible to answer. Sorry... I know nobody wants to hear that.

New things fail and used things fail. Sometimes the difference is maintenance, sometimes not. It is impossible to know how these engines have been operated or how well they have been cared for (even if you have logs, they may not be accurate nor tell the whole story). It is a gamble. About the only thing you can do, if really worried about it, is have a qualified person take a very close look and that is absolutely no guarantee of anything.

My coach had eleven hundred thousand miles on it. Still going strong. I don't know if that is with the original engine or if there was a rebuild or two somewhere in between. Will it fail tomorrow? Maybe. Will it keep running well past me? Maybe.

Some will say an engine with high mileage (and in good overall condition) is likely to continue running for a very long time.

1100,000 mies?

[JDOnTheGo]

Originally Posted by o1marc

1100,000 mies?

Correct.

That sounds better than the alternative. However; it is a coach.

[o1marc]

Originally Posted by JDOnTheGo

Correct.

That sounds better than the alternative. However; it is a coach.

I've never heard someone call a million a thousand thousands. A million one, million one hundred thou. Never eleven hundred thousand miles.

[PNW_Steve]

My Eagle had around 650k miles on it when I bought it and close to 900k miles on it when I sold it. Still ran great.

It did have an inframe at some point.

[Ronnie]

Compression check will tell a lot, and get an oil sample for analysis. Real world ways to evaluate an engine. Whether a seller will let you do this is another question....

[Ronnie]

For me I am bummed a bit. 16,500 miles, and a spun cam bearing. yuck, guess I am pulling the engine and doing a tear down see what is going on.

[glenncooper]

I've really appreciated everyone's two cents on this topic. As suspected, it's a question that doesn't offer a completely clear answer. But in the midst of this all were plenty of little pearls of wisdom for me to keep in my back pocket.

[Iceni John]

A bus with a medium-duty drivetrain (e.g. Cummins 8.3) will probably start needing attention at a quarter-million miles, and a heavy-duty drivetrain should easily double that. If it's got a pickup truck or van drivetrain, who knows? MCI built their buses for three million miles, but that was with a few engines and transmissions along the way. The weight of the engine and transmission is a good indicator of how much life to expect from them.

Take an engine oil sample of any vehicle you're thinking to buy, and have it tested to see what's happening (or already happened) inside. You can also test transmission and PS fluids and coolant, well worth it if the seller doesn't know much.

John

[cowlitzcoach]

The T444(E) and the Cummins 5.9L/6BT are good engines in a school bus out to around 300K. At that point it gets into the "how much longer until it chunks" zone.

The DT(A)360 is a good engine in a school bus out to around 350K.

The DT466/530 and Cummins 8.3L/6CT are probably good for up to around 400K.

But those numbers are extremely subjective. Two buses in the same fleet on the same maintenance schedule can have two very different lives and at the time of replacement one might have 50% of the life used up and the other one might have 90% of the life used up. Oddly the bus with the lower miles might actually be in poorer mechanical condition.

So don't pass up on a bus with higher miles just because of the high miles.

I would much rather have a bus that was used as a trip bus in MT with 300K miles than the same kind of bus of the same model year with 100K miles. You know the MT bus never was used much on stop/go to/from route work and a lot of long distance highway work. You know the route bus never went very far before it was shut off again and then restarted 20-minutes later to do the same thing again.