4D vs D

W

wutagoalie

New member
Hello all, quick question. Will driving on 4D burn more gas than driving on D ?

Im new to this 4 runner , just wondering.

Thanks
:shrug:
 
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If you aren't towing anything then yes...if you are towing...probably not but possibly. The D uses 5th gear which is overdrive. so, it helps gas a bunch on the freeway. If you just drive around town then it will probably be about the same. Hope that helps.
 
settytb said:
If you aren't towing anything then yes...if you are towing...probably not but possibly. The D uses 5th gear which is overdrive. so, it helps gas a bunch on the freeway. If you just drive around town then it will probably be about the same. Hope that helps.
Click to expand...

Yep - this. Driving in 4 will not cause any harm either because the torque converter locks in 4th as well.
 
settytb said:
If you aren't towing anything then yes...if you are towing...probably not but possibly. The D uses 5th gear which is overdrive. so, it helps gas a bunch on the freeway. If you just drive around town then it will probably be about the same. Hope that helps.
Click to expand...

I have been driving in 4D all the time, i do mainly highway driving. No i am not towing anything.

It would be cheaper for me to drive in "D".

Thanks
 
I just found this out the hard way this weekend. While driving to Fla getting back onto the highway my wife reached into the back for something for the kids and bumped the selector over to 4. With screaming kids and having driven the past month with a bad wheel bearing, I didn't notice the extra rpms. About two hours later I noticed the position when we stopped. I filled it up to see the difference and I had been averaging about 19mpg, but running in 4 I got 15mpg. Needless to say I paid more attention after that.
 
How would D or 4D matter for towing? It's basically a gear limiter (limiting OD) and allows for more engine braking. If towing in D, wouldn't the ECU just keep the tranny in 4th gear anyway, based on pedal/throttle position, conditions (hills, flat road, speed, load, etc.) if needed?

The more I think about it I suppose 4D would keep the tranny from wanting to shift into 5th and then needing to back down to 4th over and over. ?
 
bob3dsf said:
How would D or 4D matter for towing? It's basically a gear limiter (limiting OD) and allows for more engine braking. If towing in D, wouldn't the ECU just keep the tranny in 4th gear anyway, based on pedal/throttle position, conditions (hills, flat road, speed, load, etc.) if needed?

The more I think about it I suppose 4D would keep the tranny from wanting to shift into 5th and then needing to back down to 4th over and over. ?
Click to expand...

Your correct.
Some towing conditions will cause the trans to hunt. Meaning a lot of shifting from d to 4th (shifting back and forth every 3 to 5 sec) by the ecu. 5th is an overdrive. Towing increases the engine load. Plus the decreased mechanical advantage of the gear ratio. The ecu see's that and will down shift to 4 earlier, possibly to frequent. The convertor coming in and out of lock and the tiny slip before the shift locks in gear, increased by the load of what your towing, Contribute to heat in the trans while towing. By holding the trans in 4d, It prevents the hunting and reduces trans temp. The overdrive in the runner is pretty stout and can tow in 5th. But given a lot of little hills and conditions you have the option of holding 4th to prevent the trans from hunting. If it occurs.
 
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