Bought a 2005 Sport V8 with severe R and OD gears slipping, and figured it was a solenoid, valve body circuit clogged, or low trans fluid (procedures listed at bottom of my post). It wasn't any of these reasons, so now I am looking to buy a lower mileage trans from a salvage yard.

I have found plenty of 2005-2007 Tundra's with the same powertrain as my 4Runner (4.7L, 4x4), and was wondering if an A750F trans from a Tundra is a direct swap into my 4Runner.



Items performed to try to fix severe R and OD slippage:
ATF exchange using cooling line (existing level was low, but old fluid did not smell burnt - was brown in color though)
- brought up to temp, left engine running, removed overflow bolt, drained until little stream, reinstalled overflow bolt

Trans R and OD still slipping

Performed pressure test
Idling - D in spec
Idling - D in spec
Stall - D in spec
Stall - R shoots up to in spec range, but steadily drops in pressure pretty quick (indicative of circuit fluid leak)

Dropped valve body from trans
separated valve body and removed all valves for inspection
cleaned valve body (barely dirty)
checked resistance on all solenoids
installed Sonnax B1 Apply Control Plunger Kit
reassembled valve body and reinstalled
refilled ATF and verified level

Trans R and OD still slipping