Banging in 4x4, high or low, Please help !!!

[splashbusters]

I have to say I Love my stock 2004 Arizona Beige Metallic 4x4 Ranger, but I am about at my wits end with this truck. When in 4wd, high or low, there is a horrendous banging noise coming from the driveline and multiple shops (including several dealers) cannot seem to be able to figure it out (one place even told me this was the normal engagement of the 4wd system). I laughed because the noise was so bad one time that my father got out and walked to where we were going... I've had some great memories with this truck, but have basically only driven it to and from a shop since 2019. My dad wants to sell the truck because he just doesn't trust it, which is a shame, its a great truck. If I had a place where I could work on it, I'd just fix it myself, but my current living situation does not allow for that.

I first noticed the noise while in 4x4 low, engine braking going down a steep hill. It would thunk every now and then. (I want to say that binding is the correct word to describe the noise). It seemed to me to only do this with no throttle or brake inputs, just coasting down a steep hill with some load on the engine. This then progressed to making the noise while going uphill, and then into 4x4 high.

The front differential is fine, it shows a good contact pattern on the drive and coast side of the teeth and all bearings are good. I pulled the front driveshaft and I still get the noise when in 4wd (high or low, but the front end not being driven), but not in 2wd

I do have a 2002 Explorer Sport Trac with the same driveline and 150k miles and have never had an issue with the 4wd, and I'm pretty hard on that truck sometimes.

The transfer case has now been replaced 5 times. The first one went 110k miles but then I needed to replace the transmission, I told the shop to change the transfer case sine the transmission was coming out anyways. The second transfer case worked great and I never heard the noise, but then it locked up on my cousin while he was driving in the snow, after that it seem to be a QC issue. The third one worked fine, but had a crack in the side of it and was leaking oil. The 4th one was making the noise and I was told there were chunks of metal in the oil. I'm guessing something was out of tolerance because that one only went about 50 miles. The 5th and current one is doing the same thing and I'm wondering if its another QC issue or possibly something else manifesting itself as an issue with the transfer case, possibly a 4x4 control module, or shift module going out, or an electrical issue.

Any suggestions on what may be causing this problem is greatly appreciated.

 

[4x4prepper]

Well, your issue almost sounds like a bad transfer case, if you owned an AWD Explorer or Mountaineer, but, you said 4x4 so I will assume it is a real transfer case and not AWD. More then one 2004 Exploder or Mountaineer owner has solved their drive lines issues by swapping in a normal 4lo/4hi transfer case.

What I have found when hearing sounds and banging, that the bolts for the driveshaft flange have worked their way loose, and they have to be removed, blue locked tite, and cranked down at the rear axle. I have lost a few, so, I keep spare ones where possible and a 12 point wrench in my road tool box to tighten them.

A cracked transfer case would cause me to look at all mounts and if they looked good, then throw my money away on replacing the engine ones first. Since sometimes they can look good, but, still be bad, once the engine if lifted off of them. If you are not the original owner I would look at someone replacing mounts with either solid or poly which can cause enough stiffness to break stuff.

 

[Shran]

Where are you getting your transfer cases from? Sounds like maybe another bad t-case?

Sure it's not a front axle shaft or the front driveshaft? CV joints will make noises like that.

I dealt with one that would kind of sound like something was winding up inside it, then let loose with a clunk. My buddy (the owner) and I chased it all throughout the drivetrain and finally ended up replacing the t-case which fixed the issue. But narrow down the cheap stuff first, it appears that you've already done that.

 

[dvdswan]

May sound crazy but do both axles have the same gear ratio? I mean 5 t/cases?