My Kia Sephia is doing the same thing. I was told that my valve body was stuck and needed to be cleaned.
no
you need to have the bands adjusted.
IF they used the same motor and transmission, the truck with 3.55s would turn higher RPMs at speed, but would be better suited for hills. A truck with 3.55s typically will turn 1500 RPMs at 70 MPH. The truck with 3.08s would turn a lot less RPMs at speed. However, it's extremely unlikely the truck with 3.08s will have the same transmission - it would be geared much too high. It probably has a lower geared transmission than what the truck with 3.55s is using.
many things can a transmission on its way out is a big one a clutch slipping anything
major vacuum leak?
You probable don't check you re transmission fluid and its dirty or low, or maybe you played around with the auto-stick feature too much and ran too low or too high of rpms, but wither way, sounds like your transmission is going out.
check and/or replace the transmission sensor
A transmission that causes the RPMs to increase without changing gears could be in need of fluid. If that does not fix the problem, it may be the car needs a new transmission. For safety reasons, it is imperative the car is taken to a trained mechanic to be diagnosed properly.
there is no fuse that makes the transmission shift the transmission shifts on cylinoids and rpms
If you accelerate and the transmission shifts to a lower gear of the overdrive disengages the RPMs will increase. If the vehicle has a manual transmission a slipping clutch will cause the RPMs to increase if the clutch is defective.
It would depend on the gear ratio and transmission. stock tires 235/70r16: auto(O/D) with 3.55 gears =2160 rpms auto(O/D) with 3.73gears = 2270 rpms manual with 3.73s = 2360 rpms
Toyota dealers do not say the Toyota 4runner transmission is dangerous. However, there are reports that the engine will rev to high rpms and then peel out, so you may want to avoid it.