Loud snapping noise in 4x4 while pulling - possibly transfer case?

[Blakers]

My truck is an 03 2500 4x4 with 6 speed. 277,000 miles.
When pulling hard in 4 wheel drive ( like pulling someone out of the mud), I get a loud popping or ratcheting sound and the truck jumps a lot. The u-joints are good, and everything up front appears fine. I’m suspecting the chain in my transfer case is jumping teeth. Has anyone had this issue. What was your problem and cure. Driving in 4x4 with no heavy load, ie, on snowy roads is no problem, with no noise. It shifts in and out of 4x4 with no problems. Thanks.

 

[petersonj]

I've never experienced that situation, but from your description of what is happening and the associated noises I could imagine a worn out transfer case chain and teeth doing something like that. I wonder if there is a chain tensioner in the transfer case.

- John

 

[NIsaacs]

Have you checked the oil in the t-case at all? If not, pull the plug and see what you have. If that looks good pull the front diff cover. No tensioner on the chain.

 

[Ozymandias]

I heard from stretched chains, hard use, high mileage.
Open it and you'll find out.
If needed change chain AND sprockets, not only the chain.

TorqueKing is a trusted vendor for this parts, Recommended by TDR.

.....and dont wait any longer or you'll need a case to. The chain touches it and work through.

 

[Tinman]

I had a "clicking" sound only in 4wd in my 2nd Gen a few years ago. Turned out it was lack of appropriate grease in the front u Joints. I have Torque King's greaseable front U joints (and ball joints) and after I greased them several times, the sound went away not to return. I grease now every oil change. So it may not be transfer case, could be any of the u joints. I recently had the transfer case on the 01 re-built with a kit from Torque King. It was leaking but working great. This truck has had 4wd used thousands of times -no exaggeration. The re-builder said the case looked great on the inside and I had let it leak fluid down a good bit a few times. These Transfer cases are tough.

 

[KATOOM]

A ratcheting sound has me also thinking the transfer case chain is jumping teeth. If thats whats happening then it would be loud and obvious. And something you'll want to fix asap otherwise that chain will eventually snap and bust the case.

If its not that loud but more some noise coming from the front then you'll want to inspect all the front driveline u-joints.

 

[Signal73]

I had the same noise, the snap ring that holds the gear on the shaft in the TC that goes to the front axle had come off, allowing the chain to climb the gear and make the chain jump a bit before the gear slid back to where it belongs.

 

[Blakers]

Thanks for all the replies guys. I don't think it's front axle u-joints as they are both in good shape and take grease ok. I grease them when I change from winter tires to all terrain tires, and sometimes more often. Whenever I have the front tires off and I can get in there with a light to see that grease is coming out all four caps when I grease the joints.

A friend suggested that I drain the oil from the transfer case when it's good and hot and check for metallic particles in the oil, and then to put a magnet in the drain hole and check for pieces of chain or sprockets.

Blake

 

[Blakers]

I had the same noise, the snap ring that holds the gear on the shaft in the TC that goes to the front axle had come off, allowing the chain to climb the gear and make the chain jump a bit before the gear slid back to where it belongs.

Signal,
Is that snap ring on the inside of the transfer case? Was there an in and out movement that could be felt at the front driveshaft? Was the chain shot by the time you made the repair? Thanks.

 

[Blakers]

Have you checked the oil in the t-case at all? If not, pull the plug and see what you have. If that looks good pull the front diff cover. No tensioner on the chain.

Yes, I check the oil. It leaks at the rear driveshaft. I replaced the seal, but it still leaks, so I need to add a quart about every 6 months. I'm gonna drain it and look for particles and metallic appearance to the oil.

 

[Signal73]

Signal,
Is that snap ring on the inside of the transfer case? Was there an in and out movement that could be felt at the front driveshaft? Was the chain shot by the time you made the repair? Thanks.

It’s on the inside. Case needs to be split to inspect or repair. No shaft play would be apparent either. Chain was fine and I don’t recall any large metal particles in the oil either. It had popped at least 2 dozen times before I had found the cause also. Definitely a noticeable clunk right below your feet, first time I heard it I expected parts on the ground! Really only under load it would happen going down the road once the clunk happened it drove fine. My truck is a 96 but figured my story may be of help.

 

[Ozymandias]

Yes, I check the oil. It leaks at the rear driveshaft. I replaced the seal, but it still leaks, so I need to add a quart about every 6 months. I'm gonna drain it and look for particles and metallic appearance to the oil.

A leaking rear seal can also be a bad u-joint in the rear shaft.
Or the bushing in the tail housing is worn out and needs replacement.

 

[Blakers]

A leaking rear seal can also be a bad u-joint in the rear shaft.
Or the bushing in the tail housing is worn out and needs replacement.

Yeah, the bushing is worn. Maybe some day I'll replace it. A couple quarts of oil a year and free undercoating under the truck is a lot cheaper than that part of the drive shaft.

 

[Blakers]

It’s on the inside. Case needs to be split to inspect or repair. No shaft play would be apparent either. Chain was fine and I don’t recall any large metal particles in the oil either. It had popped at least 2 dozen times before I had found the cause also. Definitely a noticeable clunk right below your feet, first time I heard it I expected parts on the ground! Really only under load it would happen going down the road once the clunk happened it drove fine. My truck is a 96 but figured my story may be of help.

I bet that is what it is. I'm going to drain the oil when hot sometime and look at it. And fish around in there with a magnet. I'd like to have one of those little probes with the camera to look around in there.
I wonder if the case can be split in the truck? Probably easier to work on out of the truck, but that things is heavy and awkward.

 

[04blackcherry]

The bushing sleeve inside the rear extension housing is easy to replace (should have a press to do it). I kept having a rear seal leak after installing a new seal. Replaced it and it still leaked. Got a different seal from another source; no more leak.

 

[Blakers]

The bushing sleeve inside the rear extension housing is easy to replace (should have a press to do it). I kept having a rear seal leak after installing a new seal. Replaced it and it still leaked. Got a different seal from another source; no more leak.

Oh, you mean the bushing inside the tail shaft? I thought you meant the telescopic part of the drive shaft.

 

[Ozymandias]

Yes I meant the same.
The slip yoke usually doesn't wear.

 

[04blackcherry]

Yes, in the transfer case housing.

 

[Signal73]

May be tough to snag with a magnet

 

[Blakers]

May be tough to snag with a magnet

I was just looking for chips or debris.