My ’66 F100—with the 240 six—didn’t have the owner’s manual when I bought it in 1987. When I stumbled into one in a used book store some years later, I bought it. The other day I wanted to look something up in it, and when I opened it up I had totally forgotten about these notes written into it by its original owners(s). They document tire replacements and much more disturbingly, two major engine repairs at 24,332 and 27, 017 miles to replace the pistons, rings and connecting rod bearings. Whoa! What caused that? In an engine that is considered to be as bulletproof as any of its time?
Here’s a crop of that section. It’s a bit faded but here’s what it says:
New pistons, rings, con. rod bearing. 24,332 mi.
New rings, pistons, etc. 27,017 mi! Dec. 6, 1967
I’m struggling to to imagine what would have caused the initial damage and then a repeat less than 3,000 miles later. It would seem most likely to have been caused by a massive lubrication issue? But no other damage, as in the valve train. I’m assuming some of you will chime on with a good or likely explanation.
Here’s the inside cover, with the Warranty Number, which indicates a 2WD F100 with the 240 six, assembled in San Jose. The owners lived in Coos Bay, OR and bought it in nearby Reedsport, Or. I obviously picked this up in Eugene after moving here. The bottom of the text has this line:
We are so proud of this truck that we warranty it to you for a full two years or 24,000 miles.
Which raises the question as to whether these repairs were made under warranty.
The warranty spells out that it’s whichever comes first: the 24 months or the 24,000 miles. Given that the first repair was made at 24,332 miles and was within the 24 months, I think it’s pretty safe to assume that Ford honored the repair with a slight extension.
And given that the redo was so soon, and most likely still within the 24 months, it’s pretty safe to assume that Ford covered that one too.
Is it possible they abused the truck when it was brand new and not “broken in”? The break-in instructions were a bit onerous: no more than 40 mph in the first 1000 miles, and not to hold that speed steady, but varying it, to help seat the rings. I still find it hard to imaging that not sticking to these regime, which I suspect many/most drivers didn’t, would have caused such substantial damage.
The other notations are for tire replacements, with the presumably first set at 29,733.0 miles on March 4, 1968. That was followed by a set or recap tires at 77,985.8 miles on July 8, 1971. And then some recap snow tread tires were bought at 76,650 on Dec. 18, 1973. The next set, in size 15-8.55 were put on at Sears on Oct.19, 1974. That size is larger than any of the original tire sizes, which varied with the trucks GVW (Gross Vehicle Weight).
The base tire size was 7.75 x 15 4 ply. With the optional 1250lbs rated rear springs, 8-ply rated tires the same size upped the GVR from 4200lbs to 4500lbs. Larger 8,15 x 15 tires upped that to 4800lbs. And 6.50 x 16 tires upped that to 5000lbs.
Their choice of “snow tread” recaps suggest that maybe they drove on lots of rugged back-country roads. But those snow tread recaps didn’t last very long (8,000 miles) before they were replaced with those 8.55 – 15 tires.
In case you’re interested, there’s also the operating instructions for the overdrive. I have this 3-speed and overdrive in mine, but mine was installed later and the overdrive is set up for manual engagement, not via the automatic vacuum-regulated solenoid.
Related CC reading:
Truck Of A Lifetime: 1966 Ford F-100 – Thirty (Six) Years of Hauling Shit, Cheaply by PN
I Take My 1966 F100 On A Road Trip – And Get 21 MPG by PN
My dad bought a 57 Ford 292 V8 Country sedan brand new. Was a traveling salesman. Traded it 2 years later for a 59 Plymouth. The dealer said they had to overhaul the used Ford before they could sell it. I think (I was 12) that he finally admitted that he didn’t change the oil often enough ( let it go to about 5,000 miles). Crankcase breathing on fords were very poor in those days. White milkry substance from water in the oil.
If it were still under warranty, I may have requested a new engine the second time around. Then again, honoring the warranty 332 miles past the limit may have tempered that demand.
I’m aware that the Y-block V8, a decade earlier had the problem with top-end oiling *IF* you let the oil sludge up (and so Ford installed that bypass thing off the oil pan, IIRC?), but I hadn’t heard of any “Big Six” problem.
I’ll make a guess that 24K Rebuild was either for (1) a manufacturing problem that created the lower-end issue, or (2) an owner-neglect thing, BUT that 27K Rebuild was due to a problem with 24K Rebuild (rather than recurring defect or neglect). But what do I know?—–I’ll hope that owner got a fair shake for Ford/dealer, and that the CC Collective Wisdom come up with most-likely solution. Thanks for sharing this today, Paul!
Paul: I think you told me that the 223 six in my ’58 Ford is related to your 240 and is considered a “bulletproof” engine.
When I bought my ’58 from the original family (2 owners: father and son), I got all the original paperwork: manuals, receipts, etc. Among them was this piece of paper listing engine parts to be replaced. Looks to be a complete engine rebuild, although I have no proof this work was actually done, or when it was done.
At any rate, I have had this car since 2014 and it has been remarkably trouble-free. Regarding the engine, I have only had to rebuild the carb; replace water pump; adjust valves; new spark plugs. In 2024 I replaced the battery which lasted 10 years. This car always starts, and it idles and runs smoothly and consistently. Good power, no smoke, no engine leaks, no overheating. Drives like new!
To me this shows that properly set up (and not abused) these cars are really reliable and durable. (“The Ford Motor Company built it so you know it’s good!”–1958 advertising quote). What did them in was early body rust-out and the fact that the styling fell out of fashion rather quickly.