Transfer Case Plug Picture with metal shavings

[madcroc1]

Take a look. I just changed my transfer case oil today on my M923A2 (80W90 Gear Oil)..
Take a look at this plug with metal filings on them. Should I have it inspected? is this normal for metal shavings ?

 

[porkysplace]

Metal shavings are never a good sign.

 

[Scar59]

Bad sign, clean the plug and check it in a 100 miles or so. Might be old and accumilated from years of service and repair, then again it may be headed south. See what it looks like after you drive it. Any grinding nioses?

 

[madcroc1]

Yes Noise

Yes this is the grinding noise that immediately caused me to search for an answer and change all the fluids. I don't have an answer yet as to where the noise is coming from... It may be bearings in transfer case..


View attachment M923A2_Sound (2).wmv

 

[Scar59]

Well that was 1:11 minutes of "that's not right". Stop, do not wait to drive a 100 miles or so. Sounds like when the thottle was released, (not pulling power) it grinds. Could be bearings or a shaft retainer let go and gears are meshing when they're not ment to.

 

[madcroc1]

I think I might need a new transfer case. Anyone have one for sale ? I'll take it apart and see if I can fix it first. Does anyone have experience overhauling these transfer cases on the 939 series? This one is on a 1990 BMY Harsco M923a2.

 

[Scar59]

Just got in from the shop, sounds like you're going to be the first to find out. Haven't needed to get into a transfer case yet. Just bigger tools , the manuals are out there, might even find a good replacement unit. Keep us post as to the failure mode.
JC

 

[two.fiveM35]

What color was the fluid? I changed mine and it was black, i don't think it was changed when the truck was rebuilt. I did not change my noise though. I am draining the rear axles tomorrow. I have notice that one of the rear drum is cold after a drive, i guess I'll pull the drum also.

 

[madcroc1]

Definately was BLACK fluid. very black!!! It almost was like paint.

 

[two.fiveM35]

Can you feel the noise or anything different when you hold the transfer case shift handle when the noise occurs ?

 

[madcroc1]

Good question. I didn't grab the t/c handle when the noise was happening because I was halfway out the window trying to hear where it was coming from.

 

[61sleepercab]

Some things to check:

End play of output shafts (worn or unadjusted bearings)

Try rotating output shafts to see if excessive slop (movement between gears) caused by wear

Check universal joints some can make noise when loaded or unloaded.

Some small fillings are normal wear when gear sets mate with each other in a transmission. Coffee grounds size stuff or larger is bad news as well as pieces of needle bearings or bright looking metal.

Good luck hope it is something simple.. Mark

 

[porkysplace]

I would guess the shavings are related to this thread ; M923A2 horrible loud noise coming from the differential or transfer case - 5-Ton

 

[wreckerman893]

Csmdavis in Mississippi was parting out several M900 series trucks. PM him if you think you may need a transfer case. Might be easier than rebuilding.

 

[rangereter]

Based on availability and cost, you can definitely R&R the transfer cheaper and faster than tear-down and rebuild.
Regards, Bob

 

[two.fiveM35]

If you think its the transfer case, how about adding an additive like Lucas to see if it gets better or worse. Im thinking of removing that little driveshaft so I can lube it, not sure how hard it will be and if it has ever been lubed since the fittings are hard to get to.

 

[two.fiveM35]

Just drained the transfer case again and there was some stuff on the magnet. I felt smooth and silky and not gritty. Replaced the fluid with 50/50 mix of 80/90w and Lucus and the noise that I had quieted up 90%. At least I know it's from the transfer case, not sure what I will do next. Have you gotten any further with your noise issue?

 

[madcroc1]

Hi, Well I did the same but I used only 80w90 because if I had to drain the oil again I didnt want to throw out good lucas.
My noise quieted down significantly also infact the noise seemed to go away almost completely. There is just a very quiet rumble now. So this certainly has me conserned that there is a problem with the transfer case. I'm trying to find another one near by and reasonably priced. I had some small metal peices come out in the oil so there's gotta be a problem with it. Whats really tough to justify is say $500 for a used transfer case and perhaps $100-$150 shipping VS an entire new 5-ton truck on GL. There are going for about $1500 at the low end and many are going for $2500 - $3500