The only transmission weakness is in the gen 1 4 speed. grenade is probably a bit of an exaggeration. OD can shrapnel if used while towing a lot; the metal is too soft for it to handle towing loads, according to the internet.
I had a gen 2 with the 5 speed. It was the most reliable vehicle Ive ever owned. Thirsty pig with a small gas tank, especially for towing, but solid. Brakes weren’t great, but fine driven empty. Using aggressive pads and oem shoes worked best.
headlight refelectors grayed with age, which responded decently to disassembling and polishing.
2 other notes ... the starter is buried under the intake, which is only a big deal if you have to replace it. And there’s an electric air injection pump which runs on cold start, which sometimes wears out with age. It pumps air into the exhaust to help light the cats. I sold mine at 150,000 and the only moderate repairs mine needed were axle bearings, u-joints and center driveshaft carrier bearing. I think it needed valve cover gaskets for a minor leak around 130. At least two of its owners towed heavy with it, so axle and driveline bearings were understandable.
great trucks. my “new“ 2018 f150 has already had more problems than the tundra did.
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