I tore into a 2005 NP263XHD in a 3500 Silverado because of random "popping" from the driveline in 4wd. First thread here:
Another symptom I noticed was that shift on the fly seemed rather loud. Even at ~10mph on my dirt road 4hi engagement sounded like shoving a manual into gear without clutching, but it DID shift reliably into 4hi every time.
Unfortunately everything in the t-case looks good. Minimal on magnet, both shift forks are beautiful, rear case half is good, zero sign of pump rub, all bearings smooth and intact.
The only thing that stands out to me is the weird "staining" on the collar which engages the front output.
The reliefs here are machined and for the synchro fiber ring:
It does not just wipe off with a rag:
Really not sure what to make of this. Is this maybe due to how these cases cook off their ATF? The case was completely full with ATF when it got to me, but I'm guessing it's been serviced at some point to be as full as it was at 230k.
I find it curious that I have rough shifts to 4hi (when this collar slides) and "popping" in 4hi that strikes me as the front output maybe popping out under load, and I see this.
However, it appears merely aesthetic and I can't see how it would physically cause the symptoms. It's probably a red herring but I'm still curious how it came to be "stained" like this
@clinebarger
Another symptom I noticed was that shift on the fly seemed rather loud. Even at ~10mph on my dirt road 4hi engagement sounded like shoving a manual into gear without clutching, but it DID shift reliably into 4hi every time.
Unfortunately everything in the t-case looks good. Minimal on magnet, both shift forks are beautiful, rear case half is good, zero sign of pump rub, all bearings smooth and intact.
The only thing that stands out to me is the weird "staining" on the collar which engages the front output.
The reliefs here are machined and for the synchro fiber ring:
It does not just wipe off with a rag:
Really not sure what to make of this. Is this maybe due to how these cases cook off their ATF? The case was completely full with ATF when it got to me, but I'm guessing it's been serviced at some point to be as full as it was at 230k.
I find it curious that I have rough shifts to 4hi (when this collar slides) and "popping" in 4hi that strikes me as the front output maybe popping out under load, and I see this.
However, it appears merely aesthetic and I can't see how it would physically cause the symptoms. It's probably a red herring but I'm still curious how it came to be "stained" like this
@clinebarger
