Trailering and overdrive

[dvan1901]

I have an '06 F150 Lariat 4WD that is a 4 speed automatic with overdrive. I thought I remember seeing on here that you should not pull the boat while in overdrive; is that correct? If so, what about on the highway?

 

[Gary H NC]

Re: Trailering and overdrive

Depends on the weight of the boat.If you feel the tranny searching or going in and out of overdrive a lot then do not use it.
My boat is about 4000 pounds fully loaded and on flat highway overdrive is ok.
Any hills at all i leave the trans in 3rd gear.
Its the constant shifting from 3rd to 4th that kills them.

 

[Silvertip]

Re: Trailering and overdrive

It isn't so much the shifting between direct and OD that causes tranny issues, it's the torque converter clutch releasing that causes heat build up. Most of what people feel are direct-OD or OD-direct shifts are actually the TC releasing and engaging. Disengaged the torque converter is actually slipping a little. That slippage builds heat. Converter clutches lock the drive and driven parts of the converter when there is little load on the engine so there is much less heat build up. The converter locks only in direct and OD gears. That said, the load you are towing determines whether or not you should or should not use OD. If the owners manual says "never" and provides no load limits -- then don't use it.

 

[rich64]

Re: Trailering and overdrive

I have A nissan frontier 4cyl with a manual transmission 2wd .It is it unwise to use 5th gear when towing? I pull A 14' aluminum boat, I don't think it weighs 1000 pounds.(didn't mean to highjack the thread, just thought while we were on the subject...)

 

[steelespike]

Re: Trailering and overdrive

If it can maintain speed without struggling 5th is ok.I had a new 82 Dodge 6 cly. van with a 4 spd man.over drive.It could barely keep itself at speed on the gentle hills in trhe north country interstate 81.never mind towing my really light 18 ft utility.

 

[gstanton]

Re: Trailering and overdrive

As Silvertip says, if your tranny is "hunting" back and forth, then take it out of overdrive... or shift to a lower gear. A lot also depends on your load and the terrain you're driving. I tow my ~8000 lb Sea Ray to Fl and back from MD annually. Down on the "flats" there's no problem. If I come up (or down) through TN and VA, then there is some significant shifting going on. Just pay attention and act accordingly.

 

[45Auto]

Re: Trailering and overdrive

On your 4 speed automatic with overdrive, 3rd gear is 1:1. In other words, no gear reduction or multiplication is taking place in the transmission, the driveshaft is turning the same RPM as the engine if the torque converter is locked up. Torque converter locked up and transmission in 3rd means the engine load is coupled directly to the driveshaft. This is minimum load (less heat and wear) on the transmission.

If the boat is light enough OD will be fine. If you feel or hear the transmission frequently shifting unlocking the torque converter, don't use OD.

 

[KM2]

Re: Trailering and overdrive

Ford in the owners manual suggests to only turn off overdrive if your transmission is shifting frequently. I have a 04 F150 and it takes a pretty good load to make the tranny hunt. I never turn off overdrive with a 3500 boat and a load in the bed.

 

[kenmyfam]

Re: Trailering and overdrive

Although my Jimmy handbook says towing my just under 2,000lb rig is O.K. in overdrive I always use direct. I get the same gas mileage anyway !!!!! It does 17mpg no matter what I am doing, towing, by myself unloaded, loaded to the hilt etc. Direct makes sense as the torque converter is apparently not in the equation.

 

[Silvertip]

Re: Trailering and overdrive

On your Jimmy, direct is third gear just like high gear in any three speed tranny and the torque converter is very much in effect. The torque converter will engage only in third (direct) and OD. To prove this, put the selector in 3 and drive on a flat road at about 45 MPH. While holding your speed steady with your right foot on the gas, LIGHTLY touch the brake pedal while watching the tach. You will see the tach increase several hundred RPM. This is more dramatic if you do this on a slight grade. Just hold the gas pedal steady during the test. I recently competed a 450 mile trip towing my 18 foot pontoon with my S10 Crew Cab. There is a very long grade called the Knapp Hill in western Wisconsin that my rig goes up in third and the torque converter will not release. Although the load is about 3000#, towing a pontoon is like pulling a barn door through the wind so wind resistance is more of a factor than the load. Axle ratio also impacts how well or poorly a vehicle tows. My truck has 3.73 gears.

 

[reelfishin]

Re: Trailering and overdrive

I would not use OD on that transmission, mostly to eliminate the added load on both the smallest set of clutches in that transmission as well as the added torque converter heat. Chances are that on a heavier trailer, you may even get better fuel economy in the lower range. That is definitely the case on my smaller Ford Ranger when towing, especially around town and at lower speeds.
The 4R70/75 E and W transmissions are a pretty well proven design with roots going back to the late 70's. The weak like when towing is the converter on these. A serious trans cooler is in order for any towing but that should be a given on any truck these days. It's a very capable trans with normal use and maintenance. The later 4R75 transmissions have a better shift program but differ little from the older model.

Although I'd generally say not to two in OD, I pretty much judge by how the load feels behind the truck and the terrain at hand. I would pretty much say that if you can feel the truck working to tow the load, turn off the OD. If you were pulling a light boat in which the truck doesn't even feel, then OD would not be a problem. I would never use OD on hills.

 

[maxturbo]

Re: Trailering and overdrive

I have a 07 F150 and tow my boat loaded probably weighs around 6k. And I dont even feel its back there. It has no problem going into overdrive. And for those in NJ that know the ( i think its the ) Perth amboy over pass on the parkway. You know how steep that over pass is. And my truck stays in overdrive and keeps pulling with no problem.

 

[kenmyfam]

Re: Trailering and overdrive

I have a 07 F150 and tow my boat loaded probably weighs around 6k. And I dont even feel its back there. It has no problem going into overdrive. And for those in NJ that know the ( i think its the ) Perth amboy over pass on the parkway. You know how steep that over pass is. And my truck stays in overdrive and keeps pulling with no problem.

You dont notice 6,000lb behind you ???

 

[JSGAuto]

Re: Trailering and overdrive

"You dont notice 6,000lb behind you ???"


Yea, thats a lot of weight for a 150. Border line weight distribution needed!

That bridge isn't to bad when traffic is moving (it is on a 65mph highway). But if traffic is slow due to all those NY people trying to get off the exit there it can be a pain.

How big of a boat is that at 6Klbs?

 

[dingbat]

Re: Trailering and overdrive

I guess I'd better let my best freind know that he has something wrong obviosuly wrong with his F150.

We pulled my boat down to Va. Beach and back last weekend using his truck. going up and down the hills on Rt. 95 between Richmond and DC is was quite obvious that we had the boat on the back.

Maybe he was only running on 6-7 cylinders

 

[Silvertip]

Re: Trailering and overdrive

People's perception of trailer weight and resulting performance varies considerably. One person towing 6000# with any given vehicle may feel the load is not an issue while someone else driving the same rig may feel they are tied to a post.

 

[dingbat]

Re: Trailering and overdrive

Let?s just caulk it up as a figure of speech. Remember....we are using an overpass as a performance standard

 

[gstanton]

Re: Trailering and overdrive

An F-150 can pull most any load. Problems down the road might include a cracked exhaust manifold or a transmission that needs flushed. I've had 3 F-150's now, all passed 100,000 miles. The '90 is still plowing snow. We tow ('02 truck) the Sea Ray from Maryland to Florida and back, and a Nomad (8000 lb) travel trailer out west.

If it's your everyday vehicle, it's fine. You don't need a dually diesel to tow a normal sized boat or trailer. Just don't push it beyond reason!

 

[kenmyfam]

Re: Trailering and overdrive

On your Jimmy, direct is third gear just like high gear in any three speed tranny and the torque converter is very much in effect. The torque converter will engage only in third (direct) and OD. To prove this, put the selector in 3 and drive on a flat road at about 45 MPH. While holding your speed steady with your right foot on the gas, LIGHTLY touch the brake pedal while watching the tach. You will see the tach increase several hundred RPM. This is more dramatic if you do this on a slight grade. Just hold the gas pedal steady during the test. I recently competed a 450 mile trip towing my 18 foot pontoon with my S10 Crew Cab. There is a very long grade called the Knapp Hill in western Wisconsin that my rig goes up in third and the torque converter will not release. Although the load is about 3000#, towing a pontoon is like pulling a barn door through the wind so wind resistance is more of a factor than the load. Axle ratio also impacts how well or poorly a vehicle tows. My truck has 3.73 gears.

Tried that today in 3rd and it did not go up at all. It does in OD at 50 mph and touching the brake though. Thats what made me think direct was just that, "direct"

 

[Silvertip]

Re: Trailering and overdrive

You definitely have torque converter lockup in direct. There apparently was not enough load on the engine to make a difference. Try it again on a grade. If that doesn't work for you, let the tranny shift into third with the shifter in "3". At about 50 mph gradually press on the gas while watching the tach. At some point you will feel what appears to be a downshift. That is not a shift into second. That is the converter unlocking. Believe me, at 50 MPH you will know the difference between a 3rd to 2nd shift and a 3rd locked to 3rd unlocked. Even in town on a 35 -40 mph street in third you can watch the tach drop as the converter clutch engages.