1990 4 runner automatic 4x4 only moves in low side

SOURCE: transmission sometimes shifts hard into next gear.

Typiclly this is caused by a failing Pressure Control Solenoid. Now in some cases, since you are in the 1996 model year you may have a vacuum modulator that controls the shift firmness that can be replaced as it is externally mounted. I dont know how best to describe what it looks like, but look down on your transmission, on the front side facing the radiator and if you see a canister like device that has a vacuum line running to it, that is the vacuum modulator and you could start by replacing that and see if it helps.

If you do not have the vacuum modulator and have instead the electronically controlled version of your transmission then you will have a Pressure Control Solenoid and it, unfortunately, is located on the inside of the transmission and cannot be easily replaced without dropping the whole transmission.

The pressure control solenoid is a common issue with your transmission (4T65) and Im leaning more towards you have the electronically controlled version (4T65E).

SOURCE: 1998 chevy k1500 4x4 4

first of all your truck is already in first gear when your going down the road....lol

SOURCE: car jerks to side when shifting gears

Hi, just had this problem repaired. The lower arm bushings are bad...not the transmission. I ordered two sets from the nubira site (for the left and right sides of the car)...they are kind of like metal rings with rubber inside...this rubber dampens the shifting from the transmission. $250 - $300 job. Sure that's what it is...

SOURCE: 1990 toyota 4runner 4x4 wont lock in front wheels

your drive shaft thats turning is mabe broke or your automatic 4x4 lockers could be bad

SOURCE: transmission on my 2000 chevy k2500 4x4 pickup

your transmission has possibly been rebuilt with stronger springs put in. No worries. have been running mine for along while without any problems. Better this than slipping, but it is a bit annoying.