Overdrive while towing?

[neal]

Do folks tow while in overdrive? I've heard that you don't use overdrive while in hills, but it's ok to use overdrive while towing on relatively flat land. I got a ford f150 V8 5.4L triton and pull a 73 31' AS internationial......

[Ed Emerick]

I don't pull in OD as I have a 6 speed transmission and the truck just won't hold the gear. If it kicks in and out too often that is hard on the trans.

[JBinKC]

And I lost the transmission towing in OD with an Expedition and just out of warranty. I was only towing a 4,000 lb boat but in the very rugged hills around Table Rock Lake in the Ozarks. So my advice is, don't do it.

[jcanavera]

In non hilly terrain I pull in OD. GMC allows this with the transmission that is in our 6.0 liter, 4.10 rear axled GMC van. Usually the owners manual will give you the information regarding this. That's is where I got my info. On my half ton van the manual said no OD towing.

Jack

[dznf0g]

Jack has it right. Use common sense...if it only down shifts when going up inclines, it's fine in OD. If it downshifts and upshifts frequently just riding along, drop out of OD. Terrain, wind direction and speed all play into this.

Always read your owner manual.

[ROBERT CROSS]

On the late model GM's, the tranny will tell you when it wants to be in D.

Like the DW... it just can't make up it's mind.

[withidl]

To minimize heat and wear ideally the transmission should be in overdrive, if the computer will keep it in overdrive. In overdrive the transmission's torque converter clutch should be "locked-up", i.e. in direct mechanical drive just like a manual transmission. When the torque converter is “un-locked” the transmission is fluid coupled to the engine. The churning of the fluid in the converter multiplies the torque but also generates fluid friction heat.

As an example, my 2001 BMW X5 transmission has a "manual" mode (which I use 95% of the time), in which the computer will "lock-up" the torque converter in 3rd, 4th & 5th gears IF the indicated speed is above 60 mph. When pulling a grade I will down shift to 4th above 60 mph so that the torque converter will stay in “lock-up”. If 3rd is required I again try to stay above 60 mph in “lock-up” (rpm above 3,500+).

If the X5 torque converter is “un-locked” I will keep the engine at full throttle taking the speed above 60 mph, then lift the throttle to allow the computer to “lock-up” the converter clutch under minimal engine torque thereby reducing clutch wear; I then resume full throttle till I can maintain 63+ mph at which time I engage cruise control.

When accelerating from a stop I also lift the throttle when shifting so that the clutches can make up under minimal torque, thereby minimizing both wear and heat. This has all become second nature and I don’t have to give it much mental anguish.

[thecatsandi]

No,
I have tow/haul that prevents overdrive and uses a lower gear for starting out.

[norbert]

i love my diesel...only drop out of od when in the mountains.
norby

[barts]

I've always pulled trailers in overdrive on our 1996 F250; if the conditions are such that the engine cannot pull the hills in overdrive, I disable it to prevent cycling in and out which
does increase wear & tear.

The E40D tranny will lock the torque converter in either 3rd or overdrive; I wish it would also lock in second to hold down transmission temps on those long grades where we cannot quite pull 3rd.

- Bart

[waltero]

With a 6 speed manual, in my 6cyl Tacoma, I never use the 6th....(while towing)

[Snedwid]

Personal experience:
I have a 2004 Ford F-150 w/5.4 V8 engine that I purchased new. Since day one I towed a 17' Casita (~3700#) in overdrive. Got the 23' Flying Cloud in May 2010, and towed it in OD without a thought. While up in Maine, it started acting as tho it would jump into neutral, then fall back into gear in 10 or 15 seconds. I nursed it home to Fla gently. My local Ford dealer, dropped the oil pan on the transmission and found boocoo little chunks of metal. It was $2800 estimate to tear it apart and fix what ever was broken with a 12K mile warrentee, or $3K to just pull it and replace it with a rebuilt with a 100K mile warrentee. I chose the latter, so I don't know for sure what broke or why. The mechanic took a best quess that the problem was my towing in OD.

Bottom line:
I now punch the little button on the shift lever end and see the light on the dash that tells me the OD is off, EVERY time I start up with the AS attached.

Future:
I am fixing to buy a new tug, ( Chevy, Dodge, or Ford 3/4 + ton)and I note that none of the 2011 models pose this problem.

My advice:
Read all about it in your owner's manual; I didn't, thus my tale of woe.

[JFScheck]

Put her in Tow\Haul mode and let the transmission figure out the rest...

[Ike T]

Our motorhome transmission temps are always 10* hotter in overdrive than 3rd gear. When we tow a car behind the motorhome, get into the hills or the transmission temps exceed 190*, I lock out overdrive. No reason to stress the transmission more than necessary. The engine and it's cooling systems have a far greater capacity to absorb the extra load.

Also, not all of us are fortunate enough to have KITT in our tow vehicle.

I had to settle for Bonnie instead.

[jcanavera]

Originally Posted by thecatsandi

No,
I have tow/haul that prevents overdrive and uses a lower gear for starting out.

The tow/haul setting on my GM van doesn't change the gearing. What it does do is change the shift points. For all intents it delays the upshifts to keep the engine at optimum revs to give you more power. Likewise the downshifts come sooner and at higher speeds, again to give you more power. For example the upshift to OD when I'm in tow/haul doesn't occur until I get over 50 mph.

Jack

[dznf0g]

Originally Posted by jcanavera

The tow/haul setting on my GM van doesn't change the gearing. What it does do is change the shift points. For all intents it delays the upshifts to keep the engine at optimum revs to give you more power. Likewise the downshifts come sooner and at higher speeds, again to give you more power. For example the upshift to OD when I'm in tow/haul doesn't occur until I get over 50 mph.

Jack

This is true, but it does some other things, like raise the line pressure in the trans for more firm shifts and clutch apply pressures. I also boosts the alternator output for better trailer battery charge. In the newer trucks, it also provides for a different calibration for stability control as well as a hill start assist feature. They DO NOT change the gearing.