Pros and Cons of driving in 4 vs D

Been driving my 2013 v6 pre runner OR in 4 lately and not only is it basically a free Pedal Commander but I got a slight increase in MPG (22MPG from 20MPG)) driving 120 miles in the mountains and freeway everyday for the past week. My RPM's are staying around 1800-2200 but if it goes above 2300 I'll shift into D and it'll stay between 1500-2000. Any cons in driving this way?

Pros:
- much better acceleration
- linear pedal pressure
- more torque
- no gear hunting
- better handling
- engine braking on hills
- JUICE

Cons:
- more strain on tranny
- less MPG(debatable)
- having to manually shift back and forth
- ??

Just checking if this is cool before I go the whole OTT tune/Pedal commander route.

 

Con would just be higher engine RPM. Also, somewhat to your point, you don't want your transmission hunting for gears because it creates additional heat, so if it's going between 5th and 4th it's better to force it to stay in 4th until you're over the hill or whatever is causing it to hunt.

Pedal commander is a waste of money in my opinion, it just gives you the illusion your truck is faster because it's increasing your throttle input. If you need more power just push the pedal down more, no need to buy something that does that for you.

 

True, but pushing the pedal down more is annoying because I'll be in the 1500 rpm dead zone and keep pushing until boom 2300 rpm's and a jolt. Then drop back down when I let off a little. That can't be good either

 

Ah I see. Here's how you fix that: https://www.tacomaworld.com/threads/auto-to-manual-swap-progress.792584/

 

i stay in 4th when under 45 MPH

no issue so far and yes MPG can increase some as lugging in high gear needs more throttle, Think of a ten speed in top gear and trying to go fast right a way.

 

I treat the automatic "gear selector" in my 2nd gen like a paddle shifter. In some ways, it's the best of both worlds, I can select gears when I want and let the auto do it's job when I don't.

 

I use 4 when towing. When not towing and climbing in the mountains or steep long grades I’ll use 4. Other than that I put it in D and just let the tranny do what it was designed and built to do.

 

Not trying to be argumentative but I just don’t see the pros of everyday driving in 4.
1) when I want acceleration I just step on the gas and the tranny automatically shifts down to the appropriate gear and I accelerate whether I’m in 4 or not.
2) I don’t even know what linear pedal pressure is. Apparently I’ve done well all these years without it.
3) more torque, same as 1, step on the gas , down shifts, lots more torque.
4) in normal every day driving your truck shouldn’t be gear hunting. When climbing mountains, grades or towing yes put it in 4 and sometimes 3.
5) better handling?? I just really don’t see that. Any better handling would be negligible.
6) you should select what ever gear is appropriate for downhill braking/slowing whether it be 4,3,2 etc. not just 4.
7) Juice?? Not sure what you mean.
Again not trying to be argumentative but I just don’t see any advantages or plus’ to driving everyday normal driving in 4.

 

Nah you're good this is an open discussion.

I used to drive a 92 suburban, I know all about stepping on the gas lol. But maybe I got used to more modern cars or something but when I press on the gas I want it to consistently give me that power on the way up(from light pressing to harder). I don't like having a lull and then have it shift and rev up suddenly. Flat ground it's all good, but even a slight hill the truck waits too long to shift and give me "juice" to keep up. I'll hit the gas, catch up, and then hit the brakes, repeat.

In 4, I'm consistently getting a linear power to pedal pressure ratio. It makes the truck feel real good. I just don't wanna mess it up if im revving in the low 2000s for too long.

As for handling and engine braking, it helps on the twisty roads on the mountain

 

Does the A750 trans have overdrive bands that can wear out?

 

Driving in 4th cures my shutter, as does driving it with more throttle in D. I use 4 until 50ish mph and then shift to drive. Bought the truck from my Dad at 100k with a shutter, tried the fix in a tube and it works for a bit and comes back. Using 4th cures this and has been second nature for the last 2.5 years and 72k miles.

 

When I remember to shift into it, I much prefer 4th if it's in town or on slower 2 lane roads with any hills. We're at 5500' so we loose 15% of the motor's hp right off the top. At lower speeds when driving in D many of the hills causes the truck to kick down a gear into 4th, not a big deal but if I want a little more beans or accelerate it's often going to drop another gear because the motor was loafing along at 1500 rpm. That not a real smooth process in the tacoma. If I leave it in 4th in those situations the motor still isn't revving high and is a little closer to it's sweet spot. Giving it the beans only requires it to downshift one gear if at all and as far as I can tell if you're on a 45~60mph backroads esp with some hills there's no hit to the mileage. I've gotten some of my best mileage driving in 4th gear on 2 lane secondary roads.

 

Lugging it in 5th with the torque converter unlocked creates a ton of heat. In 4th with the converter locked you’re turning more rpm but the tranny isn’t heating up at all. The engine is also spinning freely and making good power and you don’t have to give it as much throttle as you would lugging in 5th.

 

depends on what oil you run

and if it's the 50% bogo valvoline ultimate cleaner of protection formulation maximum property

 

I keep mine in 4th around town, anything under 60KM/h really. I've been doing this for years and found I actually get better gas millage that way. It's that 50-65km/h range that I feel like 5th is too high, which happens to be the range im in like 95% of the time in the city. So I treat D like you did with overdrive back in the day and only shift into it when going on a freeway or highway.

I find that in D and in that speed range you really have to step on it to get it to downshift otherwise it will stay in 5th and work harder with slower accel. It almost feels like it's struggling when that happens too. In 4th you get waaaaay better throttle response, smoother revs, and it doesn't have to work as hard for those light accelerations.

That being said, I have a lifted DCLB with 32" E-rated all terrains plus some extra weight. So it's possible that bone stock with stock wheels and a smaller trim that 5th works better for city driving.

 

I guess with so many people getting tunes and throttle controllers that this is just how they run. It just shifts too early to save gas.

I'm probably gonna get a pedal monster(once an idea gets in my head I have to do it) but it's driving well like this.

 

I have never had my truck lug in D except for a second or 2 while climbing a grade. If it starts hunt gears I’ll pit er in 4 on grades, mountains or when towing. I’ve had 2 Tacos, a Tundra, a Ford and a Dodge and I’ve never experienced anything problematic daily driving in D. If ya all want to drive in 4 all the time power to you. Never had a problem and neither have zillions of other drivers. If it was a real thing the owners manual would direct you to do so. OM only says 4 while towing. But again drive in any gear you want, for me there is zero advantage or reason to do so. And again I’m not trying to rain on your parade, go for the gear that makes you happy.

 

That’s great. But a cool transmission lasts longer. I’ve got an ultra gauge to monitor temps and it really opens your eyes, especially for those of us that have heavy oversized tires.

But like you said, you do you. The A750 is an extremely durable transmission, it doesn’t make much fuss.

 

Not an expert but many years ago I was pulling a trailer in my old '87 GMC Jimmy 1500 in [D]. Going up a grade the tranny started disengaging and just spinning. Turned around, let it cool some and was able to go down the hill to a dealership mechanic I knew. They basically said don't pull heavy loads in overdrive [D] as it can damaged the transmission, keep it in 4th. My Tacoma is pretty heavy, so I also frequently drive in 4th gear. As mentioned, much more responsive. I understand the "let the tranny decide" but I think heavy loads uphill 4th is safer. IMO

 

The only time i drop mine into 4th is if it's searching going up mountain grades or towing the boat up a 2 lane switch back moutain road up to a lake at 6.400'. Also, drop it down a gear or two going down for short periods while cornering. Normal driving it doesn't lug/hunt... plenty of power.