At higher mileages, (125,000-150,000) the automatic transmission may not shift correctly. This can be caused by the throttle position sensor being out of adjustment or a shift solenoid needing to be replaced. Typically the transmission does not need to be completely overhauled.Google+
Car Problem Reports
Toyota 4Runner Automatic Transmission May Not Shift Correctly at High Mileages
Toyota 4Runner Problem
Drive Trains Affected: 2WD, 4WD, Automatic Transmission
Average Mileage: 179,020 mi (100,000 mi - 307,500 mi)
Visitor, 1990 Toyota 4Runner, Automatic Transmission, 100,000 mi
I have very similar problems. As for the transmission not shifting properly, there are 3 solenoids easily replaced which should correct the problems of no power at take off, needing to manually shift, or not being able find correct gear for acceleration when in drive. I found a kit with all 3 solenoids, Dacco Kit 97958, for $75 with shipping. It fixed most of my problems. I still don't have overdrive, but I think that is due to a stuck valve or bad temperature sending unit. The ECT on this transmission will not allow it into overdrive if the temperature is not in correct range. If you want to fix this yourself, it is not hard, just messy. I would recommend repacing the gasket and filter while you are at it. When you drop the pan, the solenoids are in plain sight at the bottom of the transmission. Each one is held in place by one or two bolts. If you have a 4wd, I would recommend dropping the smaller pan for the transfer case as well and cleaning the valves. This step is a little more involved and there are some small parts you need to be careful not to lose. The second item I would consider if I were about to do this project is a Transgo shift kit. I can't tell you how hard it is to do, because I haven't done it. There is a fourth solenoid there, but it is not necessary to replace if you do not have problems going in and out of low 4wd. I hope this info helps someone.
I was stuck unable to move thinking I was going to have to buy a new transmission after having replaced the solenoids. I worked with a friend who is a mechanic. We cleaned the valves in the transfer case and I was back on the road.
We have shift problems when we are driving down the highway. it is like the engine is having to work harder to keep up to highway speeds. It will get up to 60 Mph but anything other than that you have to hit the ECT button and then the engine revs very high like up into the 5.2k rpm. I have changed out the tranny fluid and the filter and it does shift ALOT better now but still has the problem of running or keeping up the speed on the highway. ie 70mph.
Visitor, 1995 Toyota 4Runner, 223,000 mi
My Runner will not shift into overdrive unless the vehicle has been driven for some time. It's worse in cold weather. Last night, it wouldn't shift above 2nd gear. The "check engine" light comes on when it's been sitting in below freezing temperatures. Probably the low 20s or less.
Visitor, 1993 Toyota 4Runner, 4WD, 183,003 mi
O/D warning light flashing at non predictable intervals. also pressing on gas pedal at a stop light and not having any power. not currently fixed but will be very soon (just found out what it is).
Truck will not shift out of first gear, must do it manualy. No passing gear. Check engine light is on and it the code is for the solenoid.
Visitor, 1992 Toyota 4Runner, 200,000 mi
truck periodically will not shift into drive at initial start-up. Will very often shift fine after warm-up. Occasionally will not shift into next gears without letting up on the accelator. Drives ok some of the time.
Took to dealer and they said transmission was beyond repair - they have no parts for it - it has the A340 transmission so I'm puzzeled that this tranny is not reparable??? Or is the dealer pullint a fast one to have me purchase a new transmission at what would end up costing more than the car is worth?
Visitor, 1995 Toyota 4Runner, 149,000 mi
Just noticed today it takes more rpm to move off the line, hard to tell if shifted into 2nd, acts as if slipping in 2nd. This just happened... I'll report problem & solution after consult w/mechanic. Using synthetic oil. I checked oil, it is ok. Very puzzled.
Visitor, 1992 Toyota 4Runner, 180,000 mi
will not shift down at a stop ,must shift manually
on my 93 manual states that until car reaches operating temp it will not shift into overdrive
Visitor, 1995 Toyota 4Runner, 4WD, 127,000 mi
over drive gear not working