4WD Actuator or Transfer Case Motor?

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Hello,

I have a 2007 Dodge Ram 1500 4x4 with the 4.7. When it is cold outside the truck can be slow to switch into and out of 4wd, but the big problem now is when I turn the switch from 4wd to 2wd, the 4wd light goes off pretty quick, but the truck will travel 1/2 mile or less and truck will thud real hard. It sounds and feels like the front driveshaft just broke. It's harder the faster you are going. It's hard enough where it's going to break something if it hasn't already. I'm thinking it's the 4wd actuator in the axle or transfer case electric motor in the side of the transfer case, but I really don't know.

Thanks
 
If it’s temperature related it may be the actuator. Not sure about Dodge but the GM ones had a reservoir of oil that was heated by an electrical element and expanded the fluid to engage the front hubs. Worked slow in cold temps.
 
I would think if the truck is really fully in 2WD, you could rotate the front driveshaft by hand while parked. It sounds like the transfer case is stuck in 4WD, and you get a harsh result when the axle disengages at speed. Does 4 Low work?
 
I am thinking it may be the other way around. I think the transfer case disengaging under load would cause a bigger thump than the axle. It does seem like cold would affect the transfer case more as it is running in oil. Where the axle engages there is only a small amount of oil in the bottom of the axle tube. It is hard to say without seeing it in person.

It really sounds like you just need to wait for it to disengage before driving down the road.
 
Originally Posted By: iunderpressure
Hello,

I have a 2007 Dodge Ram 1500 4x4 with the 4.7. When it is cold outside the truck can be slow to switch into and out of 4wd, but the big problem now is when I turn the switch from 4wd to 2wd, the 4wd light goes off pretty quick, but the truck will travel 1/2 mile or less and truck will thud real hard. It sounds and feels like the front driveshaft just broke. It's harder the faster you are going. It's hard enough where it's going to break something if it hasn't already. I'm thinking it's the 4wd actuator in the axle or transfer case electric motor in the side of the transfer case, but I really don't know.

Thanks


If you haven’t changed your transfer case fluid within the last 50,000 miles, that would be a good thing. Just as easy as an oil change.
 
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Sorry I wasn’t clear. The slow disengagement and engagement may or may not be related with the hard disengagement. According to the 4wd light the disengagement happens quickly in these warmer temperatures, but I will still get that hard thud usually 1/4 to 1/2 mile later. It does it every time. I drive really slow and basically just roll until I feel it trying not to break anything. I’m sure the fuild needs changed too. I was going to get all the parts at the same time. I just wasnt sure which part would cause that hard release.
 
I wonder if the light goes off as soon as the axle disconnects, then the thud is the transfer case shifting. You may try shifting to neutral and see if that makes a difference. Or get a helper to drive while you listen for the noise from outside of the truck to isolate where it is coming from.
 
The axle doesn't it is just a splined coupler that locks the two right side shafts together. The transfer case has gears that have to get lined up. So it needs the gears to either rotate freely or be turning.
 
Is this something new, started happening, when it didn't used to?
Are your tires all the same brand, size, properly inflated?
I usually like to manipulate the throttle a bit at engage / disengage to provide a little driveline slack to facilitate the shift.
 
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If there is a thud, then regardless of the light, it is not coming out of gear and the driveline is under torque loads. It is possible that motor moves into the 2H position but the prawl is spring-connected, waiting for a tensions to ease so it can work out.

Does this truck only have a t-case or does it also disengage the front axle? Neither is happening. It's possible that it wants the axle to disconnect first (if so equipped) and then the tcase releases when there is no tension.

Try reversing slow after switching to 2H, even reversing with a mild turn in steering. maybe rock it back and forth a little D/R until you feel it let go.

You are right, something will be damaged by continual use this way.

-m
 
Originally Posted By: meep
Does this truck only have a t-case or does it also disengage the front axle?

-m


The truck engages both the transfer case and axle. I think the problem is with one of those two motors.
 
Originally Posted By: JetStar
Is this something new, started happening, when it didn't used to?
Are your tires all the same brand, size, properly inflated?
I usually like to manipulate the throttle a bit at engage / disengage to provide a little driveline slack to facilitate the shift.


I don't use this truck a lot. It's mainly used to get firewood, hunting, to pull a trailer, or bad weather. I noticed it this past fall, and it has happened pretty much every time that I've put it in 4wd since.

Everything on the truck has stayed the same.

I've have tried shifting out of 4wd at different speeds, in neutral, in reverse, on snow, and even if I'm crawling I feel that thud. Reverse may make for an easier disengagement.
 
Shift into what you think is fully 2WD and park the truck. Reach underneath and try to turn the front driveshaft by hand. If both the transfer case and the axle have disengaged, it should turn.
 
It's not uncommon for 4wd actuators to get tired. Maybe I'm old school but I prefer manual hubs and a real handle. Back and forth after shifting two 2wd, especially if it's in a slow arc can do a lot to take the tension off the driveline.

-m
 
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