Engine/Transmission (1994 - 1998) Four Wheel Drive Problem!

[edgeman]

I own a 1997 3500 4X4. Last year before I left on my deployment to the middle east with the Army I noticed that my four wheel drive didn't work. So I pulled the actuator off of the front axle and checked to see if the actuator still moved the forks left and right. It did that fine when i put air to it and pulled the air from it. Also when I shif t the transfer case into gear the transfer shifts fine and my gear ranges are good. But the front axle doesn't engage. Is there a Vaccum leak in the lines or is something else wrong. I come home in 12 days and the snow has hit and i will need the four wheel drive so any help before I come home would be nice. By the way Happy Thanks giving from Iraq!:-laf

 

[kenny61]

When you saisd you checked axle acuator did you put your own air to it or use the trucks vacum. If you didn't see what happens with the trucks vacum

 

[edgeman]

ok that sounds like a good plan... . I just did it to the Actuator... . how would I check the trucks air

 

[JDKammin]

A friend of mine just fixed his. He was not getting any vacuum to the acuator on the front axle. He started with the lines at the engine and worked down towards the transfer case and front axle. Ended up the steel lines were corroded thru from Michigan winters. He found a used set at the local salvage yard and had to take the switch off the transfer case and clean it out of rust. Once he did this, he had vacuum to the front axle. He did have to replace the wear pads on the shift fork and noticed his RH seal is torn up, but now has 4x4.

 

[wcjp]

On my 96', the problem was a vacuum leak at the transfer case. I had to cut about 1" of vacuum line. Then extend the lines to fit with new vacuum hose and extensions. At the TC, there are four vacuum lines. In a pinch, you could reroute the vacuum line directly to the actuator at the front axle. This will make the the two piece axle shaft assembly constantly spin just like the 01'+ trucks.

 

[edgeman]

A friend of mine just fixed his. He was not getting any vacuum to the acuator on the front axle. He started with the lines at the engine and worked down towards the transfer case and front axle. Ended up the steel lines were corroded thru from Michigan winters. He found a used set at the local salvage yard and had to take the switch off the transfer case and clean it out of rust. Once he did this, he had vacuum to the front axle. He did have to replace the wear pads on the shift fork and noticed his RH seal is torn up, but now has 4x4. - How did your friend find out his steel lines were corroded... . and I like the sound of the Axle shaft assembly spinning constantly... Please let me know more

 

[WilsonF]

If you get under the truck w/engine running, take the rubber fitting off the CAD. Have someone shift in and out of 4WD you can feel the vacuum pull from one side to the other. Two ports on the rubber fitting.
Floyd

 

[edgeman]

ok now everyone try not to get confused. the name edgeman is used by several diff people. Me Ethan My brother Andrew and My dad Larry. this is ethan who is in mighian, andrew posted the original ? This is for my brother. Andrew i will look at the actuator before you get home to make sure it is not bent like mine and i will check the vaccume. if the pin is not bent then when i get it to you when you come home then check the red and black vacume lines at the actuator with brad or someone pulling it in and out of 4wd. call me tonght or when you get a chance. start there and then go from there.

 

[edgeman]

andy your actuator is junk i put it on my truck and it dosnt work. im taking it apart and we will see what happens. i know for sure that there is vacume on my truck.

 

[Rhondasway]

I had this happen on my '97 some years ago. 4WD worked fine then quit suddenly. Mine was because a little rubber vacuum line came loose near the wire bundle above the engine. I'd check that first. I don't remember exactly where, just look around for a loose line.

 

[Woodenhead]

When I had this problemit was a combination of a leaky diaphragm in the actuator and a sticking vac. switch at the transfer case. Parts are easily available here http://www.quad4x4.com/Dodge%20Transfer%20Case%20Parts.htm

 

[RAMnDART]

What I am doing with my vacuum actuator is replacing it with a manual actuator. I bought mine at 4x4 Posi-Lok - 4WD Engagement Systems for $231. 58 part number PL400 for my "96. I do not have it on yet but don't see any problem with it. Easy installation and all it takes is a simple 1 inch pull on the cable from inside the cab and shift the transfer case in to 4 wheel drive and you are set, no more vacuum problems. I will keep you all informed as to how well it works.

 

[Woodenhead]

What I am doing with my vacuum actuator is replacing it with a manual actuator. I bought mine at 4x4 Posi-Lok - 4WD Engagement Systems for $231. 58 part number PL400 for my "96. I do not have it on yet but don't see any problem with it. Easy installation and all it takes is a simple 1 inch pull on the cable from inside the cab and shift the transfer case in to 4 wheel drive and you are set, no more vacuum problems. I will keep you all informed as to how well it works.

And now you'll also have the ability to use low range in 2WD which is great for backing up trailers

 

[charlessmith]

A friend of mine just fixed his. ...

He did have to replace the wear pads on the shift fork ...

What is involved in replacing the wear pads on the transfer case shift fork? My 2500 4x4, 220,000 miles, has developed a whine out ot the transfer case area, I suspect it is the shift fork making the noise.



I'd hate to drop the transfer case and find nothing wrong. Is it likely that I need to put a bearing kit in the transfer case?



The 'singing' whine is sort of speed related, load or what gear the transmission is in does not change it. It starts around 40 MPH and becomes more pronounced as I get to 65 or 70 MPH.

 

[LVJUNIOR]

ditto on the posilock. Just added one on mine for a hunting trip. Was in and out of 2hi,4hi and 4 low for 5 days straight without a single hickup