how many people tow in 4 instead of drive

Just wondering if its bad at all to tow in 4 with a automatic. I'm use to trucks with the tow/haul button which these trucks don't have. Or am I better off leaving the truck in drive.

 

I've used both towing a '73 Firebird on a dolly for several hundred miles. Didn't seem to make much difference on my '06.

 

I only use 4 when going uphill

 

I would only tow in fourth unless on a long downhill. I usually downshift to fourth on every hill in everyday driving.

 

On most larger trucks (Ford F-350 1-ton, for example) the Tow/Haul button disables overdrive and changes the shift points to keep the RPMs higher (more Tq and HP). You won't need to stay in 4 if you are towing a light load, especially with a S/C. But if you are towing something heavy and the truck keeps "searching" between 4th and 5th (basically overdrive) you should go ahead and put it in 4. 4th will also help on a downhill, but if you're hauling a beast of a boat/similar get the trailer brake assist installed. Safety always when dealing with brakes.

 

x2, I tow in D unless the truck is constantly hunting for gears, then I'll push it down to 4. For flat towing, I can usually tow in D, for hills, I use 4 to keep the truck from constantly downshifting on the uphill and for some engine braking on the downhills.

 

OK here is the scoop on this related to our 5 speed Tacoma transmissions in the Gen2s:

The 5th gear is an overdrive (OD) gear. An OD gear attempts to achieve high speeds with lower engine revs - which results in minimized torque but better fuel economy on the highway.

The "brains" in the transmission will sense a load and automagically shift into 4th gear. 4th gear is a direct drive gear and designed for towing.

You can safely manually put the transmission into 4th gear while towing. I do.

Letting the transmission decide for you is problematic...

1) The transmission is always sensing for that load you are hauling and whenever it doesn't detect it the transmission will switch into 5th. This is sometimes described as "hunting" as the transmission keeps clunking back and forth from 4th to 5th to 4th... This is most likely to occur on up or down hills.

2) You only get engine breaking when NOT in OD. So on a downhill if you like that the transmission doesn't pick up speed unreasonably that is engine breaking. On steep downhills I always manually shift out of OD to take advantage of this.

So in summary, there is no harm in just putting the transmission in "D" and letting it decide what is best. But if you are willing to trade a little fuel economy for a better overall towing experience then manually shift into 4th for the duration of the towing.

As was mentioned, some light loads of about 100lbs or less may not even be worth bothering about. But as the load approaches or exceeds 3000lbs it is a reasonable concern.

I always leave my truck in 4th when towing. It gives me better control of the vehicle and my trailer and load. Also, consider putting the truck in 4th when off-roading. I always do this... the transmission will still auto shift through the gears, but avoid OD. Who wants less torque to the wheels off road???

 

I drive my Auto like a manual all the time anyways.

 

We said all of that, only less "scientifically"

 

That part I bolded isn't accurate. If you're riding the brakes in D going down a long hill, the transmission will kick down a gear to 4 so the engine holds the truck back. You can get engine braking in D, it's just not quite as predictable and I think, with a load attached, it's better to start decending the hill in 4 rather than wait until you need the brakes then try to switch over.

 

OK, OK. I was trying to sum it all up. Let me try more brevity:

• No engine braking in OD = more brake wear and heat damage to brake pads
  
• Excessive shifting "hunting" in "D" = wear on transmission parts
  
• Higher transmission temps in OD when towing caused by high vortex flow in convertor = shortened life for transmission

 

Since the owners manual actually instructs you to tow in 4, I'd say no... It's not bad

 

I'll be towing a camper that will weigh about 4,500. And if I decide to tow in 4 do you shift back into drive when decelerating and accelerating

 

No, those are the times you want to be in 4. When flat land cruising, then you can switch to D if the truck will stay in 5th and not constantly downshifting to hold it's speed.

 

I'd have to disagree on this one, at least for me, while on D as soon as I take my foot off the gas the engine braking begins regardless of speed/ decline. At times it's even annoying because I just can't coast.

 

X2 what Mike said.

And for the love of sweet baby Jesus, get a brake assist controller if you don't have one... That camper weighs as much as the truck.3

Mine doesn't seem that aggressive at all. Normally only engages when I get on the brakes going downhill and the truck shifts from 4th to 3rd.

 

By putting the truck in '4', it simply limits the truck from shifting into OD/5th. It has no other effect, and the truck will still downshift/accelerate through the gears normally.

 

Agreed, engine braking in D is fairly effective as the torque converter is still locked. If you shift into 4th without getting on the gas, converter is unlocked and in my experience similar to engine braking in D with converter locked.

 

Toyota tech tells me that this is not correct. Trans temps stay about the same. I tow 5,400lbs fairly often, generally LOTS of hills. He said tow in OD and pop it into 4th if it starts hunting.

 

The higher temps are caused by the torque convertor not being able to lock up. When the torque convertor is unlocked, the transmission can build up quite a bit of heat. That's the reason you put it in 4 when it starts to hunt for gears. In reality, it's not hunting for gears, the first time it revs up, it's just the torque convertor unlocking, the next time it revs higher it's downshifting into 4.