Agreed, except for the slow part. I've owned FJ62's and an HDJ81 and the 1HD-T is a monster by comparison. Acceleration and hill pulling capabilities are quite respectable, even in a 5400lb Cruiser. A bit of tweaking and it was even better. Loaded down with an off-road trailer, 2x RTT's and four people with all their camping gear the 81 would still cruise easily at 75mph and pull hills at 65+.
Some of the other Toyota diesels, though...that's a different matter.
The issue with using the stock transmission is that the diesels came with different transmission internals and torque converters. I've heard that the gas engine spec transmission isn't happy hooked to a diesel, though I don't have personal experience with that.
A stock 1HD-T is a fairly good match for a 1FZ, a mildly tuned one is way better IMO. Just for giggles, here are the results from some dyno runs on a bunch of Cruisers. Check out the difference between the three 1FZ's and the 1HD-T. All engines were in stock form.
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