So my 83 SR5 Daily driver is just pushing over 242,012 miles. The motor and Trans are all original. The timing belt, oil and power steering pumps have never been replaced. I did the 3rd clutch for it when I got it. I also only serviced or replace the water pump, brakes all around and shocks all around and have driven it now for a little over 37,000 miles over the last 3 years.
EDIT
I forgot to mention I only payed $200.00 US. With a jump, I drove it home after sitting for 3 years.
EDIT
There is now no such thing a sure shift. No amount of finesse makes it better. 1st, 2nd and 4th make horrific thunks. At 3k rpm's in any gear there is a hum that is awful. Nothing below or above 3k though. I drive 38 miles a day just to got to work and am normally doing between 55 and 85 on the highway depending on traffic at 31mpg average.
So how long do you think it could last?
Any one have a trans make it to 300K w/o being overhauled?
250k or 265k seems more possible but maybe not?
The big bore block is done at the machine shop and a rebuilt trans is waiting already.
It's just a waiting game now. I'm trying to drive it gently but well see. AAA gona need a flatbed when it breaks.

So all you guys running 200k miles plus on your first(original trans) chime in.
I'm bet'n 254k. Hoping for 260k though.