Towing with/without Overdrive

[demarko210]

I always have my overdrive to the on position. When I turn off I get the O/D off light. I was wondering if anyone turns overdrive off while trailering their load?

 

[Scott Danforth]

I use the trailer button. changes shift points and when the last shift is done.

 

[matt167]

Agree. Use tow/ haul if you have it... IF you just have an overdrive switch, for sure switch OD off... And if you have an older Dodge, keep OD off all the time and the trans will last forever

 

[demarko210]

Its a 2002 Mercury Mountaineer 4.6, had the transmission rebuilt about 5k miles ago. I suppose I should have asked the Tech that question. Thank you for your input guys!

 

[dwco5051]

Depends on what you are towing and the topography. If you are pulling a 12' aluminum boat I would leave it on. Towing 6000# turn it off. You have to get the feel of it. A long up grade and the tranny is constantly shifting up and down to maintain speed turn it off. I pull any thing from a 600# boat and trailer combo to excavating equipment and I sorta figure if over 1/3 my max load rating I leave it off.

 

[matt167]

That's a 5R55S, which dates back to the A4LD. I would for sure pull it out of OD. Towing in OD would get the trans a bit warm, and then they tend to have solenoid problems that you will feel with a reverse delay and eventually get an extra neutral when you loose reverse

 

[dwco5051]

That's a 5R55S, which dates back to the A4LD. I would for sure pull it out of OD. Towing in OD would get the trans a bit warm, and then they tend to have solenoid problems that you will feel with a reverse delay and eventually get an extra neutral when you loose reverse

Should have added to my post my tow vehicle is a 3/4T Duramax with the 5 speed Allison. Since you know that tranny I hope he takes your advice if he is hauling any thing more than the weight of 4 adult passengers.

 

[Sprig]

In general you shouldn’t tow in OD. Doing so can over heat the automatic transmission and cause transmission failure. Each vehicle has its own set of instructions for towing and it varies by vehicle make and year. Towing in OD or not will be covered in your vehicle owners manual. Consult your your owners manual.

 

[demarko210]

My boat is 2700# 230 Sea Fox WA. I am not sure if the Manufacture gives the weight on full tank or not. Highway I am usually going around 55-65mph at about 1800 rpm. No load hold around 1500 at that speed. That is with the OD on. I will run with OD off I would suspect the rpm will climb with OD off. Thanks everyone, I will look for my manual.

 

[Scott Danforth]

weights published are dry weights of the boat only. some do not add the weight of the motors (outboards)

add the 1200# for the trailer and 300# for fuel, then add your gear.

 

[Alumarine]

My boat is 2700# 230 Sea Fox WA. I am not sure if the Manufacture gives the weight on full tank or not. Highway I am usually going around 55-65mph at about 1800 rpm. No load hold around 1500 at that speed. That is with the OD on. I will run with OD off I would suspect the rpm will climb with OD off. Thanks everyone, I will look for my manual.

Are you saying when not towing your boat your rev's are 1500 and with the boat at the same speed its 1800?
If so, I suspect the difference is your torque converter is not locking up when towing.
Not locking up = heat = bad.
Maybe that's why you needed your tranny rebuilt?

 

[demarko210]

Are you saying when not towing your boat your rev's are 1500 and with the boat at the same speed its 1800?
If so, I suspect the difference is your torque converter is not locking up when towing.
Not locking up = heat = bad.
Maybe that's why you needed your tranny rebuilt?

Tranny had 250k miles on it bought it with 98K. I decided to rebuild because every time I change the fluid I loose gears when setting on a incline. It would go away over time but I know it should not happen and my plan was to put miles on a new tranny with the boat. If I would not have changed my fluid the last time I probably still have that 3500 in my pocket and would not have done the rebuild yet but my plans we to do the rebuild. It just came sooner than expected. Tranny was load but still shift ok before the rebuild. Now I dont even notice that the gears are changing when pulling the trailer. I had them do the main seals and oil pan gasket with the tranny.

Yes when I am riding on the highway flat with the boat doing 55-65 its at 1800-1900. With no load it rides at 1500 at those speeds. On a hill it jumps timing at about 2800-3000. I try to keep it under 3200k if I can.

 

[H20Rat]

Yes when I am riding on the highway flat with the boat doing 55-65 its at 1800-1900. With no load it rides at 1500 at those speeds. On a hill it jumps timing at about 2800-3000. I try to keep it under 3200k if I can.

Yeah yours trans isn't happy doing that. If you still have overdrive on, that increase in RPM is the unlocked torque converter. Really bad to run down the highway like that. I'm guessing if you turned off OD you would end up in the 2800 rpm range, basically your trans is shifting down on its own.

With my boat, there is zero chance I can tow in OD, it is at the limit of the vehicle. But when I'm pulling my snowmobile trailer, i can get away with shifting into OD on flat sections at 65 mph. On the interstate at 75, I have to stay out of OD otherwise it will keep bouncing in and out of torque converter lockup. (I actually don't have an OD switch, I have full auto 5 speed or manual shifting. So I end up running manual shifting most of the time.)

 

[Cortes100]

For me, it all depends on the weight of the trailer load. The boat is in that 2000-2500 range so it doesn't matter. However when pulling my enclosed sled trailer, sometimes tow mode, or I lock out 9 & 10th which are the OD gears. Also in tow mode, the tranny senses slowing down so it down shifts to help stopping

 

[demarko210]

Look at the manual after hunting it down. It stated
Deactivate overdrive when:

• driving with a heavy load
• towning a trailer up or down steep hills
• and additional engine braking

 

[444]

It really depends on the load and transmission. Generally however if you find your transmission is frequently downshifting and hunting in/out of overdrive to maintain speed, I would suggest pulling it out of OD. Those constant gear shifts are not good. All my vehicles are stick because I feel automatics are hot garbage, especially for towing.

 

[demarko210]

I trailered the boat yesterday with OD off. It did not do the constant shifting. Traveled about 55-65mph and it rpm maintained at about 2200-2800 rpm all the way down and up the highway.

 

[dingbat]

Traveled about 55-65mph and it rpm maintained at about 2200-2800 rpm all the way down and up the highway.

That would drive me nuts… see nothing above 1800 unless the engine brake kicks in.

 

[demarko210]

That would drive me nuts… see nothing above 1800 unless the engine brake kicks in.

Your truck pull the load under 2000 rpm when you travel?

 

[Drcoffee]

Overdrive allows the torque converter to be unlocked to save gas and make the drive more enjoyable. But trailering in OD with the torque converter unlocked causes a serious transmission heat problem. Its best to tow in the next lower gear like 4th gear and have the torque converter locked.