So i think i found a donor can please bare with a newb here
 

Okay so i have a 1990 pickup with 5spd r150 trans 2wd that had a 3.0

Ive sourced a 3.4 in a 1999 4runner also with 5spd trans but is 4x4 obviously

from my knowlegde sofar it seems like the wiring will obviously be a little bit different but for the most part i can just not use the sensors associated with the 4x4 option and things will work.

my biggest concern is the ecu. can anybody confirm that the donor vehicle im looking at will be a good option for my swap as far as ecu and wiring is concerned and/or any other downfalls i might see using said donor as opposed to another say earlier or later year donor?

any advice is much appreciated

thanks in advance

In my vast experience (1 successful swap) a manual swap to a manual should be no ECU issue. The ECO and engine harness wiring for the trans only has switches for reverse light, 4X4, and high/low (depending on year). On mine, I had to add a relay for the backup lights and a ground circuit for the reverse indicator switch but other than that it worked. I did not use the hi/low range indicator since there isnt anywhere to display it on a early EFI truck dash. I thought the R150 2WD was different than the R150 4X4, but Im not certain of that - I had to have an adapter to mate my R150 to my dual gear-driven xfer cases. O/W you should work. I would replace the clutch on the 3.4 since its probably pretty worn depending on the mileage on the 4Runner. Use the 3.4 clutch, throwout etc.

God luck!

Forgot somthing. Anything after 1995 will need more than a pnps jumper to work without throwing codes. That said the tranny codes will not put the transmission into limp mode, they will just be an annoying engine light. All this information is in the A/T diagnositcs section of the TIS and cheating the codes from appearing is as simple as seeing the conditions required for the code to be set and finding a workaround.

its manual to manual, no issues other than proper wiring. you are also upgrading to ODBII so you will need to add the diagnostic port. make sure you get that from the donor.