Towing: the Overdrive question V6

[PeteB88]

I did a search, couldn't find the answer - What's the bottom line regarding Overdrive ON/OFf when towing? I have heard never have it on w/ towing. What's the deal? I tow maybe 300 lbs to 2000 at times (Boston Whaler). I don't drive fast when I tow anything, maybe 60-65 max, mostly 55-60. I'm thinkin' OD is okay on the flat but punch Off when climbing.

I appreciate any advice on this.

Thanks

98 V6, Limited, auto, 4WD

 

[SubSonic]

You will likely get varying opinions and a bunch of "facts" to support those opinions, so I'll give you mine.

NEVER tow anything in Overdrive that surpasses the "payload" of the vehicle you are using. Like my PWC, weighs less than 1000lbs total, wet, trailered...and my Tundra's bed-borne payload rating is 1000 lbs (half ton). I tow it in Overdrive often and have had no issues. Anything heavier and I will leave OD off, period - no exceptions.

Apparently, OD is usually a gear that is hung way out on the end of the cog set and is the "weakest gear" in the transmission. But it's my opinion that no owner's manual anywhere that I've ever seen ever says to disable OD when the bed is full (meaning maximum payload) so I take my chances with lighter tow loads - even though I probably shouldn't. I also use OD when towing my utility trailer (about 500 lbs) with my lawn mower on it (also about 500 lbs).

Another reason not to "tow" heavier loads in OD is using your tranny/engine as a brake-helper. If you're in Drive, your engine and tranny will assist you in slowing more than being in OD would.

I don't plan on towing much with my T4R since I do still have my Tundra. Even with 135k miles on it, and years and years of towing (from 1000lbs to 6200lbs), she's still hanging in there like a hair in a bisquit...but I do disable OD on all but the lightest of loads.

 

[maine runner]

Pete -

When going on the highway or above 40, I turn it OFF, regardless of the grade being flat or hilly.

I also use the ECT button. Not sure you have that feature on your 98.

 

[Clemsonfan15]

Pete -

When going on the highway or above 40, I turn it OFF, regardless of the grade being flat or hilly.

I also use the ECT button. Not sure you have that feature on your 98.

'98s have ECT as well as every other 3rd Gen.

To be safe I would keep it off when towing anything.

 

[smokey7722]

I've never heard of this. I tow anywhere from 500lb trailers to some pretty beefy excavating equipment. So when towing anything pretty heavy I should NOT be in overdrive? On my '05 I've got the normal 5 speed auto, would I be right in assuming the overdrive is on when I put the truck in D? Turning it off would just be shifting to 4? Sorry if this sounds stupid

I also just noticed the thread title was for a V6, does it matter for my V8? Is there a difference?

 

[peter78]

On my '05 I've got the normal 5 speed auto, would I be right in assuming the overdrive is on when I put the truck in D? Turning it off would just be shifting to 4? Sorry if this sounds stupid

I also just noticed the thread title was for a V6, does it matter for my V8? Is there a difference?

This is in the general discussion, so it can pertain to any 4Runner. You are right about 4th gear, it is not overdrive, 4th gear on your V8 is 1.0:1. Also, on the 4 speed transmission, whether it be a 3rd gen. like PeteB88's 98 or the 4th gen. early model V6, the ratio is 1:1. That is the gear you want to be in when your towing.

As far as using overdrive when towing, the problem is when in overdrive, excess heat can build up, even if your towing level. I tow my pop-up trailer and it is around 2,100 pounds loaded. I do use the overdrive. If I am going fast enough and it is level or down hill I might use it. My 01 has a built in transmission cooler, but I know heat of the transmission fluid is the enemy. If it is flat and not straining, after awhile, I will turn off the overdrive. When on a downhill area I will turn it on. I tend to trun off the overdrive 50% of the time. My Wife who doesn't really like turning the overdrive on or off, will simply drive for 1/2 hour with it off and then 1/2 hour with it on. Just keep in mind the transmission is a tough transmission and if you carry a some what light loead, under 2,500 pounds, using the overdrive once in awhile, may not be that bad of a thing, IMHO.

 

[fourwd1]

... As far as using overdrive when towing, the problem is when in overdrive, excess heat can build up, even if your towing level. ... If I am going fast enough and it is level or down hill I might use it. My 01 has a built in transmission cooler, but I know heat of the transmission fluid is the enemy. ...

Correct, heat IS a transmissions worst enemy, and the trans cooler is in the radiator, so it doesn't do the best job.

If you do a lot of (or even a little) towing, it's a good idea to install an aftermarket cooler.

And keep the OD off, unless your on a nice flat area, or down hill.

 

[Bluesky 07]

Reviving an old thread b/c this is useful information. I knew I had seen the answer re: not towing with overdrive in the manual somewhere but could never find it again, until now. This is on page 164 of the 2007 manual:

They cite the need to maintain engine braking capability but I'm sure the effect on the transmission is also a factor. In any case, keep the selector in "4" when towing and be mindful about it since using "D" is such a muscle-memory/habit thing in everyday driving.