Thats a great point. The 8.3 isn't a class 8 engine like the Detroits and Cummins in Crowns. 300k+ in a school bus route is HARD use.
That's truly a lot for an 8.3 in harsh school bus city service. And you're right, it's a medium duty engine. Probably won't hold up well at all for sustained high speeds and long hours of highway driving. All of these I've driven shake and vibrate a LOT at idle, so bad in fact they had to add a fast idle switch so it wouldn't shake the bus apart. Even a Crown can be shook loose with this amount of vibration over years of service. The original school district near San Diego didn't keep these long at all and dumped them....for probably many, soon to be found reasons for any unwitting new buyer. Low torque means bad hill climbing, excessive vibration, unknown high mileage engine issues to be dealt with, and they aren't cheap to fix either, just because it's a Cummins doesn't guarantee it's superior or cheap to keep.
It looks good and been polished up real good by the seller, who obviously isn't knowledgeable at all about buses, or Crowns for sure, and is only in it to flip it, FAST, to a victim, and run away even faster.
I also don't believe for a second his description of how fast this one goes down the road. Read it carefully and you'll see "it's the fastest Crown he's ever driven", it's most likely the ONLY Crown he's ever driven, ever, and only because it has an automatic transmission, which makes it like a Really big car. He's no driver, or ever been around them enough to know what he's on about.
A typical fast talking, know nothing, lowlife wannabe, used bus salesman. I think I can promise this R.E. 8.3 powered, School District Crown only goes about 63mph, as that was all they were geared to do. But what does he know, 60mph probably had him hanging on for dear life, IF, which I doubt, he even got it going that fast. He most likely thinks that, quick off the line, as this will do when empty, really means it's good on the road, or in hills, NOT, and that it must be Really Fast. Like I said, he was hanging on for dear life trying to keep it in his lane no doubt. I've seen it many times before. Pffft.
His quaint description of the other Crown he has, made me laugh. No pertinent info at all, to cover up his total lack of even a rudimentary inkling of what he was talking about, or trying to impart, and it could be a piece of trash, and probably not running, and/or in pieces, as if he would know or care.
This is a Classic case of: You Pays your Money and Takes your Chances. You could easily spend more, (much more?) to repair it than you paid for it initially . But heh it's a Crown so what could possibly go wrong, right? Even I have my limits, based on reality and the economics of things.
Most definitely a huge Caveat Emptor. You've been warned.
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As an aside, I happen to have a Crown right now for sale that will be needing it's engine rebuilt, but it's all included in the price I'm asking of $15K. It's a 35ft two axle with a 6-71 and an MT643 Auto transmission. I'll be doing a full in-frame overhaul of the engine, with kits and liners, and everything will be checked out. When it's finished it will be a turn-key, refurbished Crown, ready for another 3-400K miles and thirty years of use. It was parked when the District Drivers managed to crack the head, while it was in daily CHP certified service, excellently maintained, with none of the deferred maintenance so commonly found on most Crowns available today. Tires, brakes, suspension, air system, electrical, are all in top shape and ready to go today.
So it's been in limbo and waiting for someone to see the underlying high quality and low mileage on it, only needing engine work to bring it back into full Commercial Revenue Service Condition, if so desired. A true diamond in the rough.
I'll stand by this one and am open to inquiries from anyone looking for the finest example of a long lived Crown, ready for untold thousands of miles, and decades of use, while always safely bringing you home again, with a lifetime measured in decades, and which will still probably manage to outlive them.