Truck shifts out of gear at 50 to 60 miles an hour jumps in and out of overdrive at those speeds

The erratic jumping in and out of overdrive (O/D) on your 2006 Terrano 3GMR with a 3.2L engine could be caused by a few different issues. Here are some possible causes and fixes:

1. Faulty speed sensor: The speed sensor provides input to the transmission control module (TCM) to determine when to engage overdrive. A faulty sensor can cause the TCM to think the vehicle is going too slow or too fast for overdrive engagement. A mechanic can test the speed sensor and replace it if necessary.
2. Low transmission fluid level: Low transmission fluid level can cause the transmission to shift erratically or not engage overdrive. Check the transmission fluid level and add fluid as necessary. If the fluid level is low, it's important to also check for any leaks that may be causing the fluid loss.
3. Worn or damaged overdrive band: The overdrive band is responsible for engaging and disengaging overdrive. If the band is worn or damaged, it may not engage properly. A mechanic can inspect the overdrive band and replace it if necessary.
4. Transmission control module (TCM) issues: The TCM controls the shifting and engagement of overdrive. If the TCM is malfunctioning, it may not engage overdrive or cause erratic shifting. A mechanic can test the TCM and replace it if necessary.

It's recommended to have a professional mechanic diagnose and repair the issue, as the transmission is a complex and vital component of the vehicle.

It always starts out in first, it's a 3 speed automatic, that's what automatics do. they start out in first and at about 15-20 miles per hour , they shift to second gear, and when the speed is about 35-45 MPH, the transmission automatically shifts into third gear, or Drive.

Bigger automatics have 4 or more speeds. Till recently, 4 speeds were the norm, and fourth gear was often dubbed Overdrive, as it allowed the engine to run slower in 4th gear, than it had to maintain speed in 3rd gear, drive. It's good, it increases your mileage per gallon of gas, so you save that way, but like all things more complicated, they cost more to fix when something goes wrong.

You are lugging the engine. Overdrive is only for use in top gear when you get to cruising speed to reduce the engine speed.

run the fault codes
say whether it is auto or manual as both have over drives

OVERDRIVE is fine in most driving. if you tow a trailler or pulling long hills take out of overdrive. otherwise the vehicle will handle when to shift.

Over Drive..... Generally speaking, overdrive (OD) is the highest gear in the transmission. Overdrive allows the engine to operate at a lower rpm for a given road speed. This allows the vehicle to achieve better fuel efficiency, and often quieter operation on the highway. When it is switched on, an automatic transmission can shift into overdrive mode after a certain speed is reached (usually 70+ km/h [43+ mph] depending on the load). When it is off, the automatic transmission shifting is limited to the lower gears. For an automatic transmission, it is almost always best to select overdrive and allow the transmission to control engagement of the overdrive. (It may be necessary to switch it off if the vehicle is being operated in a mountainous area or when towing a trailer.) With a manual transmission, overdrive should usually be selected when the average speed is above 70 km/h (approx. 43 mph).

Try and adjust the down shift cable..Sounds like either it is broke or out of adjustment..

I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_a3369546f8067589

Sounds like your pressure silenoid is going out in the transmission. This controls when the vehicle shifts

Hi. 2005 Corolla CE. It's normal. They tend to do this when upshifting form 1st to 2nd gear. No timing chain readjustment needed.

96 Corolla. Overdrive not working properly, if not engaging after 45mph constantly. If driving on the city, is normal, but not after 45mph, when the car is trying to engage overdrive in order to save gas and preserve the trans gears. If not able to get help at the dealership, find another one and explain them the situation.