97 850 common things to look out for

[Stephen Henning]

But hey, feel free to disbelieve me, and to think
that those fluids are Immortal. ;-)

Following manufacturers recommendations doesn't make anything immortal
and never will. It just means using good sense and not getting paranoid.

They apparently did both. The transmissions that weren't defective
tended to fail at or above 100k miles because they were still running
the original fluid. IIRC, Volvo didn't even have a usable filler hole
for it on the early ones...

That is because the parts were designed wrong and eventually failed
depending upon how hard the transmission was used. They all failed. It
had nothing to do with fluid. It was a weak part. Nothing wore out.
They just quit one day when the part failed. That is completely
different than a ware out scenario.