I've looked in the owners manual and found nothing. What is the minimum trailer weight recommended to engage the tow/haul button on the 09 4.6 3v, 6 sp tranny? We were in the smokey mountains last week and I had some issues with the engine/tranny on the inclines, I called the dealers service department, talked with a service advisor and he told me I don't need to use the tow/haul mode unless I'm towing 4k or better??? Does that sound correct?

I'll post more on the problem I had later.

 

the tow haul button is just a renamed overdrive on/off button

i never use it going up hill loaded or not but down hill i use it all the time to hold the truck back

 

Tow haul mode, changes the shift strategy, and raises the line pressure, to reduce the chance of slippage, causing heat build up. It is recomended always when towing or hauling.

Unlike the old days, when the tranny's had OD, the old version simply turned off the OD. The new design, doesnt have the OD but another gear, and The tow haul mode switch, will change the perameters of the shift requirements. Holding gears longer, downshifting earlier, not unlocking the converter, on decents, down long hills reducing brake fade.

I personaly recomend using it, even if pulling a shrub, or tree out of the ground.

I would also add Ford doesnt put an exact weight, on when it is advised to be used, because then there are variables. This way, if you are towing or hauling, use it. Keeping it simple

 

On One steep decent there was a stop sign at the bottom, I was in Tow haul mode, when I started to apply the brakes at the stop sign the truck acted like it wanted to surge forward pushing the truck, I applied brake firmly and shifted to neutral to avoid a car in front of me, then the motor quickly reved up to about 5500 rpm then back down.
I tried it again at another decent and it acts like it still wants to surge forward. I took it out of tow haul mode, completed our vacation with no further problems. Anyone had this problem?

 

I guess the question is, Why would you pull it out of gear, when it is downshifting???

These new tranny's do everything themsleves...It took me time to get used to mine, If you think you have a problem, I would take it back to the dealer, and have them check the tranny out, it is simple, and they plug it in, and if you tell them your concernes, they can adjust them to your habits, and advise you on, what is acctually happeniong.

 

Sounds more like the cruise didn't disengage.

 

When it surged it was pushing the truck forward, the brakes were acting as if they weren't working, I shifted into neutral to stop momentum. I possibly over-reacted seeing that was the first tow on steep roads and me not being used to the tranny.

 

When the truck down shifts, it might rev high and feel like a surge at first before it begins to slow the truck down using the tranny. As it down shifts, it revs high to minimize the impact on the shift as it lowers gears, and the added weight of trailer likely just gave you a little scare as the computer began its tow haul compensation effort. Also if cruise in engaged and you shift into neutral, the truck will rev looking to maintain that speed with no place to put the power. Try it with out the trailer in tow haul and let it do its thing. My guess is, it will work fine.

 

What you felt was the trans using engine brakeing to slow you down. Many people who have driven auto's are not used to engine being used to brake. Many Manual users know it well. The engine is just dropping gears and reving high because your going into a lower gear. It will sound as if your going faster but you are infact slowing down. Mine does it all the time when im towing. It's a nice feature to have and it makes it function more like a manual when towing. A lot less wear and tear on your brakes.

 

Whenever I tow, I use the Tow/Haul mode and anytime I am coming down a hill I am already slowing down if I feel I may have to stop. I would rather be slow going then to lose a skid loader or a load of hay. I never use the cruise control when towing (maybe if I were on the flats out west but too many hills around here) I tow a 24' deck over flatbed 90% of the time and I am always checking the load and how it's bound, maybe I am super cautious but I have never lost a load. Chris

 

Originally Posted by hanklin
Clarify this a bit for me please,my 01 has the O/D button on the shifter(auto) now isn`t that the same thing as T/H mode?

No, it's not. Your O/D button only locks out overdrive. I don't think it makes any other changes to the shift points.

The tow/haul button does not lock out O/D. It changes shift points to better keep the motor high in the torque curve. But it will still use all the gears when appropriate.

Bill is very knowledgeable ,this is his take and I agree

 

Are you using a brake controller Barry?

 

No, No brake controller.
I pulled a little lighter trailer all day today in the tow haul mode didn't have the first problem.

 

When I had my 05 F150 I used a prodigy controller. What I learned was to disconnect it after evey trip, because it tries to "learn" your braking habits and adjusts accordingly. I didn't know they had integrated the tow/haul on the 1/2 tons. But what you were describing as surge leads me to believe you need brake control.

 

Your controller should turn itself off once trailer leads are disconnected if not then it's wired wrong. Use the supplied harness that came with your truck for correct connections. I believe that the 2005's had the O/D switch which is equal to Tow/Haul? Both switches either take or lock up the overdrive feature or in the 2009's trans the 6th gear, if I have gotten this right from other posts. Chris