94 automatic ,4x4 when cold will not shift it to over drive ,talk to trans, shop said there was a sensor ,I thoght he said in the radiator any one know of this or any help thanks

 

Not posative, but I think that it won't shift into overdrive if the tempature isn't high enough because of emission reason. Maybe check to see if your thermostat it functioning properly.

 

First of all, the 3.0 V6 that you probably have in that 4runner is barely good for 85 mph on a flat road, uphill it's worse. There is no sensor in your radiator that prevents you from going into overdrive, all overdrive doe's is shift into 4th gear when you are on the highway for a little more speed and for your rpm's to drop back down for better gas mileage, but it really doesn't help much. The reason your truck is so slow is mostly because of the 4:10's in the rear differential, which are truck gears, these are awsome trail gears (for stock rigs), towing gears, etc. High way gearing is more along the lines of a 2:50 ratio, but you loose all of your low end torque. Give us some more info on your truck (motor, etc.) so we can help you more.

 

This is correct. Needs to warm up before O/D kicks in.

1stgen4gunner is not correct

 

Once the motor gets warm, it'll go into OD. The first time I borrowed my old mans truck last year I thought I broke it because it wouldn't go into 4th gear at all. Then the truck got warm and it went nicely in OD.

 

so have to let it sit in the drive and warm up each time before driving ,even in warmer temp?
1stgen4gunner I live in IL,where it doesnt get any flatter ,it is a pickup ,not a 4 runner ,and it has 513 gears

 

Could also be the temp. sender for the A/T computer, if it reads too low, it'll think the engine is cold and will block out O/D operation.

 

thank u where is this located

 

A Factory Service Manual would show the location, links to some on this forum. I know on the 22RE engine, typically it is screwed into the t-stat housing on the engine.

 

You don't have to wait for it to warm up. It'll just rev higher.

 

I'm in the same situation. 94 3.0 v6 auto 4runner geared 4:88. Has to reach normal operating temp to switch into OD. Was told it was a governor on the transmission. I also thought that maybe it was something in the cooling system, but literally replaced every cooling component and the truck ran 10 to 1 better, accept the OD. So I could be wrong, but i think its normal. Haven't researched it though because it doesn't bother me too much unless i have to go above 50 right off the blocks.