Caterpillar 3406E
Among the most admired truck engines ever built in North America, and the one people mean when they talk about old Cats. Electronically fuelled, mechanically simple everywhere else, and famously long-lived.
Output
355-550 hp
1350-1850 lb-ft peak torque
Fuel per mile
$0.675
at 6.0 mpg and $4.049 a gallon
Fuel a year
$80,980
over 120,000 miles
In-frame overhaul
$16k-$26k
rough, and shop rates move it
In the exhaust
None
Before exhaust gas recirculation. Mechanical or lightly electronic, no filter, no fluid, nothing in the exhaust to clog. They are old, they are dirty, and owner-operators still pay a premium for them for exactly one reason: there is far less on them that can strand you.
Known issues
Age. Everything on a thirty year old engine is a wear item, and rebuild parts, while available, are no longer cheap.
Verdict
Bought for longevity and the total absence of exhaust hardware. It will not be economical and it will not be quiet, and that is not why anyone buys one.
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