Overdrive switching in and out while towing.

I have and 02 Dakota 4.3L V8 with Factory towing package and the upgraded rear axle gear ratio. When I use it to tow my small teardrop trailer (less than 2,000 lbs) I have a problem with the Overdrive constantly switching in and out. This happens even on flat straight-aways with the cruise control on, but Only when I am doing over 67 MPH (If I am driving 65 and under, it does not switch out.)

I feel as if this engine should have no problem towing this trailer at

70 while in Overdrive. I can easily push this trailer around with 1 hand in my backyard, and it it very aerodynamic in shape.
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My Question: Is there some sort of adjustment that can be made to whatever tells the tranny to switch out of overdrive? Or should I just eat the extra gas cost, turn off the overdrive and drive in 3rd gear at

3,000 rpms (vs 2000 or so in Overdrive.)
Reply to
fracassa
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im betting if you read your owners manual it will tell you not to tow in overdrive. check your owners manual for all special concerns when towing with your specific vehicle.

Reply to
Christopher Thompson

I had a 93 Dakota with the same engine and towing package and the Owners Manual specifically stated "NOT" to tow in overdrive.

Don

Reply to
Don Dunlap

I have a 94 Dakota with 4.7 and the manual says it's OK to tow in overdrive unless driving in hilly areas where the transmission shifts a lot. I pull a 1780 GVWR pop-up frequently and don't have any problems with towing in overdrive on the Interstate at 70. I pulled a 4700 load cross country and only felt a need to shift out of overdrive when entering the hilly areas in TN and VA. Of course both of those trailers probably had less frontal area than your teardrop. I would think the T@B would be just as easy to tow as the pop-up though, since teardrops are supposed to be more aerodynamic. I have the standard rear axle, so it would seem that mine should have more trouble than yours with staying in overdrive. I believe your T@B has surge brakes, could it be actually coming forward enough to activate the surge brakes and cause extra drag at the higher speeds, kind of like race cars when they draft the car in front? I used to tow a camper in England that had surge brakes that you could "lock out", so if you can do that, you might try that to see if it changes anything. Doesn't seem possible, but aerodynamics can be strange sometimes. Is the trailer level? Are the tire pressures of the tow vehicle and trailer set to the correct specs? Are you driving into strong headwinds? Any of these items could cause enough drag to tell the engine that there's additional load other than just the trailer weight.

JPH

Reply to
JPH

Really?

Reply to
.boB

It depends a lot on the load and the rear axle ratio. If it has a pretty tall axle, it will hunt a lot like yours is. Lock out OD while towing and performance and MPG while towing will improve and it will extend tranny life too. BTW, Dodge never had a 4.3 V8, it is a 4.7.

Reply to
SnoMan

Hmmm, after reading your post I did some looking into your theory. Since the camper is teardrop in shape, it may be possible that it is acting as an aerofoil at higher speeds and actually giving lift or movement in any number of directions? (Possibly engaging the surge brakes.) But, I would expect that the hubs on the trailer would be getting hot if this was the case. (I had checked, they are not.) I will try locking them out - thanks for the suggestion. If that doesn't work, I will probably stop using the overdrive.

Correction: mine is also a 4.7L

Reply to
fracassa

Just a guess, but your gear change (assuming 3.93 or 4:10?) would have you turning higher rpm at freeway speed.. doesn't seem like that would make a transmission hunt, but logic doesn't always apply.. *g*

Mac

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Reply to
mac davis

Oops, meant 2004. At least it ends in a 4!

JPH

Reply to
JPH

====== ====== ~~Answers to yer question~~ (IF....and only IF...all else is well with the truck)

Go to the Dealership. Tell them you want the latest update version installed in the controll module for towing. There "IS" one.

also.... There's a harness available aftermarket that changes the shift strategy of the transmission..specifically to aid in towing situations.

there are more options... those are the 2 best... in descending order of "my" preference.

Fact...not Fiction

~:~ MarshMonster ~takes a slug of his mushroom tea..mmm...good stuff~

Reply to
Marsh Monster

Just got back from the Dealer, almost the first thing out of the tech's mouth was "you shouldn't be towing with Overdrive on." He pretty much blew off the idea of doing a software update on the control module. That being said, when you say aftermarket harness, are you talking about those performance chip updates? If not, can you tell me what I should be searching for?

I still think it should be able to tow this realtively light trailer with o/d on.

Reply to
fracassa

My '03 Durango with the 4.7L tows a 6x10 enclosed that's around 2000 pounds loaded 1200 empty + around 800 gear). I have to switch OD off only when pulling moderate hills or longer, but not as steep, uphill stretches. It will move along at 70 in OD most of the time. It never hunts, even at 40-50 mph.

I found that load> Just got back from the Dealer, almost the first thing out of the tech's

Reply to
Iman Nassoul

======== ========

The upgrade needs to be done first.

and......

I don't give damn what the "dealer" tech said.

and....

If you'll gladly invite him here...... I tell him he's full of sheet for you...

cuz.....

he is.

any whooo.......no it ain't no "chip".

it is... what i called it.

a harness.

and....

i am so upset right now with you, for allowing some tweeb arsed, wanna be, 5 year trainie, book smart, no sensed dealer wanna be tech........tell you i was full of sheet.

so....go google it.

p.s. i'm not mad at you..... jest yer ignernce. ~:~ MarshMonster ~knocks back a shot.....and fills his glass.......grrrr~

Reply to
Marsh Monster

MarshMonstor, Please excuse my ignorance - I am learning this crap on the fly here. I appreciate your input immensily

I will go to another dealer and and not let them blow me off so easily.

But, I don't understand how replacing a harness can change shifting characteristics without some sort of chip. I can find a ton of performance chips that claim torque improvements, etc.. and I have been googling my arse off, but the only "harnesses" I can find are for adding a trailer connector (ie: stop/turn lighting and braking.) Nothing that effects the tranny.

Throw a guy a link?

Thanks again, Matt

Reply to
fracassa

Ya, I was about to ask the same question about this one and 93 and a

4.3L in a previous post.

JAM

Reply to
Adolphe Menjou

Ouch!

I also have a 04 Dakota with a 4.7L.

It's the worst lemon I have ever known.

JAM

Reply to
Adolphe Menjou

What you have to do is tell them what to do.

Factory trained technicians are trained not to think, just do what they are told.

The only way to fix the problems with my 04 Dakota was to do this. I would be told that they had no instructions from the factory on how to fix the problems. The would ask me "what do you want me to do?". At this point I would hand them a print out of the cause and remedy for the problem.

JAM

Reply to
Adolphe Menjou

======= ======= good form.......

The links, the TSB concerning the symptom, and further rantings from me are on the way.

and...... I appologize to all good Dealer Techs....... which are VERY FEW and far between.

Trainies are a dime a dozen.

~:~ Marsh ~sips his Heineken.....off to the Files~

Reply to
Marsh Monster

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