ECT and OVERDRIVE buttons?

[4x4Runner09]

Im learning but can you describe exactly what the ECT and OVERDRIVE buttons do on my 00 V6?

When I use ECT it seems like the holds a lower gear longer and revs higher?

When should I use them? Leave em on or off all the time?

Use em in 4wd or no?

Thanks for any replies!

 

[Thai]

4x4,

ECT will probably give you 0.00000001 second advantage in acceleration! Well, actually, it only functions to hold a gear a bit longer before upshifting (aka slightly more aggressive shifting). By doing so, you may see a slight decrease in fuel economy. That's about it. You can use it whenever you want. It does not affect anything else. Some owners have it on all the time. For me, i don't ever use it...it's not like i will win many races these days with other SUVs.

Your automatic transmission has 4 forward gears (and 1 reverse gear). The first three gears are NON-overdrive gears, used mainly to get you going...that is, it has ratios of > 1. Here are the gear ratios for your 4runner:

1st 2.804
2nd 1.531
3rd 1.000
4th 0.705 <---- Overdrive gear!
Reverse 2.393

For example, your first gear ratio is 2.804, which is > 1 (as is gear #2 and #3). The 4th gear ratio is 0.705, which is < 1. This is your overdrive gear, used to conserve fuel economy, smoother crusing, and decrease stress on powertrain.

Your automatic transmission will shift into OD (overdrive) whenever you're cruising (at most speeds) to decrease engine noise, conserve fuel, and decrease wear on powertrain. However, in OD, you won't be able to accelerate very well because it's main function is to conserve fuel, not acceleration. When you press harder on the gas pedal, your tranny will downshift out of overdrive to one of the first three gears (usually down to 3rd gear) to provide more spritely acceleration. Once you've relaxed your foot from the gas pedal, it will shift back into OD.

The OD button is to keep the tranny from shifting into 4th gear (OD gear). This is useful in off-roading where you may not want the engine to shift into OD, such as going across rough terrain in 4-HI (you will not likely go into OD when in 4-LO because speed will be too slow). By doing so, you won't have any lag time when you accelerate. Why lag time? Well, same as above, in OD, your engine is "relaxing...shooting the breeze". Therefore, it is lazy during this time to accelerate. To get it up and going, you have to press hard on the gas pedal to force a downshift OR press the OD button.

Another common place to lock out OD is during heavy traffic. This will prevent your 4runner from shifting into and out of OD...basically, by locking out OD, you decrease shifting activity by allowing the tranny to only use the first three gears. Less stress on your tranny by doing this?? I don't know since Toyota tranny is so darn reliable and bulletproof.

Hope this helps.

BTW, OD gearing (< 1.0 ratio) is usually the 5th gear on a 5-speed manual transmission. In the new 4Runner (2003), the OD gear is the 5th gear on the new 5-speed auto tranny.

 

[peter78]

Thai is right, the ECT will raise the shift points. I was told it is used for towing, 4 wheeling, driving in mountians or just plain aggressive driving. As for towing, I was told to put the ECT button on and the overdrive off.

Turning off the overdrive button makes your 4Runner stay in 3rd gear, not 4th gear. I have used this feature on hills, were you want a lower gear. Either for going up a steep hill or going down one. Also if you leave your overdrive on when towing, it tends to overheat the transmission.

Personally, I never use the ECT button.

 

[4x4Runner09]

woa what an explanation!!
I cant wait to try ECT and overdrive now what I know what they are!
Would you recommend turning OFF overdrive for high speed passing? Cruising at 70-75 then passing in the 80's-90's...

Driving up to Mammoth I gota pass all those big trucks

Anywayz...thanks for the explanation and your time? Thats just one more thing I know about my 4Runner!

 

[peter78]

Remember the overdrive is usually left on. As far as passing, if you step on the gas, if the transmission needs to downshift it will by itself ;and then upshift by itself. So no you don't have to take the overdrivew off.

Now if you on a 2 lane road going about 50 and you need to pass a truck, taking the overdrive off before you pass may not be such as bad idea. It is a little like downshifting a stick shift before you pass. The rev's are now up and the power is there and you don't have to wait for a downshift.

Most of the time you don't need to push the ECT button or the Overdrive button, you basically just have to step on the gas. Still if you understand what those buttons are for, you can enhance your driving and/or driving style.:ufo:

 

[Thai]

Yeah, Peter beat me to it. I forgot one very important function of the OD button...towing. When towing something, lock out OD (press the button for it to be OFF). This will decrease stress on your powertrain during towing, especially your torque converter.

As far as normal driving goes, just leave the OD on. If you need to pass someone, just press harder on gas pedal...the tranny will downshift out of OD for you. But, Peter's right, in mountain driving, OD off may help because it prevents gear hunting (shifting in and out of OD...aka 4th gear) and helps in passing slower cars.

 

[4x4Runner09]

one more question or actually two...


Say Im cruising on a straight highway at 70-75 constintly then I need to pass a truck in the opposite lane. I pick up too about 85-90....should I take OD off?

what about offroading...just messing around on some moderate trails?

thank you!

 

[Thai]

4x4,

If you want to pass someone on the highway, you can just press the gas pedal harder to force it to downshift (out of OD). But if you're just plain lazy to use your leg muscle, then you can push the OD button, which will force your tranny to downshift to 3rd gear (out of OD)...then you can press the gas pedal to accelerate past the truck.

In off-roading, it's up to you. Most people shut OD off (i do). I do this to prevent it going to OD (remember: OD = less power due to gear ratio being < 1.0)...thus preventing your tranny having to downshift if you want to power up a hill...saving you a little bit of time because with OD OFF, you're already in the 3rd gear. This is similar to why people shut off OD in heavy traffic...two reasons:

1. You can pass someone quickly without waiting for the transmission to downshift out of OD; and

2. Less stress on your tranny (in theory) because it does less shifting (3 gears to shift instead of 4 gears). Again, this is a theory...i don't think i have heard of one tranny failure due to heavy traffic.

Again, when towing, shut off OD.

(Remember, the 2003 V8 4runners have the 5-speed auto tranny...and the 5th gear is the OD.)

Hope this helps.