Front diferential fail

[Skibum1681]

Id bet its pretty spot on for a pinion bearing to tight.

I assume these still use a crush washer; making it tough to over tighten - on the initial install, in a factory setting. I presume OE diff's aren't set up by hand are they?

A tight pinion bearing, that was tight enough to make "a lot of metal" would certainly have a lot of play in it at this point wouldn't it (meaning the bearing is starting to come apart)? If the pinion bearing was coming apart wouldn't there be other noises coming from the front diff due to the pinon flopping around?

 

[shermanator2]

Something doesn't add up here.

OP took it in for a squeal. No grinding, no clunking, no vibration, no indication that the 4wd doesn't function and the dealer says its junk??

I don't doubt the OP's symptom but I highly doubt the dealers diagnosis....

I agree. But the dealer said there is lots of metal in the gear oil. That alone to me means complete differential rebuild or replacement. That may not be where the squeal is coming from, there may be two problems here. I have not figured out where the squeal may be from. There is actually less relative movement in the hub in 4WD than in 2WD, so that leads me away from there. I am wondering about some debris rubbing the half shaft or stub shaft. Don't know, just throwing out a guess.

 

[Skibum1681]

I wonder what "a lot of metal" is. Are we talking chunks, or sparkly oil, or that metallic film on the cover?

Edit: t sounds like they didn't pull the cover yet.

Anyone know if the plug has a magnet on these?

 

[Skibum1681]

They said it was a lot of metal. Only 12,000 miles and very few times probably 20 I ever used it in four-wheel-drive and not for long period it still doesn’t make sense to me that it would make a squeal out of the front left wheel if it’s in the differential.

Your logic sounds good, but the diff is left of center on the axle which if it is coming from the diff it would be more noticeable on the left side.

 

[Devenhallen]

I assume these still use a crush washer; making it tough to over tighten - on the initial install, in a factory setting. I presume OE diff's aren't set up by hand are they?

A tight pinion bearing, that was tight enough to make "a lot of metal" would certainly have a lot of play in it at this point wouldn't it (meaning the bearing is starting to come apart)? If the pinion bearing was coming apart wouldn't there be other noises coming from the front diff due to the pinon flopping around?

Nope, You can get a tight pinion. It will get so hot it will weld the bearing together as it squeals. I am fairly certain the newsest ones still use the crush sleeve.
Im not sure on the assembly side of things. This is just a solid indicator of a pinion bearing being tight and just heating itself till it welds itself together. The next thing that will happen is the bearing cage comes apart and will lock up the ring and pinion.....

 

[Devenhallen]

This is what you’ll find when this Happens..

 

[Tominator]

Nope, You can get a tight pinion. It will get so hot it will weld the bearing together as it squeals. I am fairly certain the newsest ones still use the crush sleeve.
Im not sure on the assembly side of things. This is just a solid indicator of a pinion bearing being tight and just heating itself till it welds itself together. The next thing that will happen is the bearing cage comes apart and will lock up the ring and pinion.....

Thx!

 

[Tominator]

Your logic sounds good, but the diff is left of center on the axle which if it is coming from the diff it would be more noticeable on the left side.

Thx!

 

[JCleary]

Arod on YouTube did a video on a squealing left hub in 4wd. Had to replace a seal. Did not look fun. I have same issue, but only in freezing temps. 4wd is fine when warm.

 

[JCleary]

 

[Devenhallen]

This is what I was thinking, but that wont produce metal .

 

[Maine Guide]

Excellent video, I don’t have that tool may have to get it, since I don’t have a socket that size either. Thanks

 

[Sccritterkiller]

That's what that sound is. Noticed that sound since the beginning of hunting season..knew it was sonething in the hub...I will get them to look at next time it's in for service..

 

[DLayne]

Have had similar issues, first time was a hub seal as mentioned previously and a broken vacuum line connector. First, two times 4WD worked by manually turning hubs in. This time still squealing, grinding and clunking in 4WD and manual. I think some metal is normal in most 4wd diffs, chunks no. 5 weeks for parts? Sounds about right these days. I am 6 weeks out just for an appt. for a tech to look at it in our area. All the damn Zoom people who moved here during covid and no new techs!!! Good luck! I feel your pain! Only 30k miles on truck.

May be going back to GM…ZR2 Bison edition with Duramax Tunner tune

 

[Tominator]

Have had similar issues, first time was a hub seal as mentioned previously and a broken vacuum line connector. First, two times 4WD worked by manually turning hubs in. This time still squealing, grinding and clunking in 4WD and manual. I think some metal is normal in most 4wd diffs, chunks no. 5 weeks for parts? Sounds about right these days. I am 6 weeks out just for an appt. for a tech to look at it in our area. All the damn Zoom people who moved here during covid and no new techs!!! Good luck! I feel your pain! Only 30k miles on truck.

May be going back to GM…ZR2 Bison edition with Duramax Tunner tune

Thx! I‘ll post as this progresses

 

[Sccritterkiller]

If it is a gear issue I would want the entire front end replaced...not saying they can't but installing gears probably doesn't happen everyday in dealership especially on Dana axels...you have to put the carrier back in the housing to check backlash...I have regeared a couple smaller Dana axels it's a tedious PIA job unless you get your shims right on the first try...I have never been that lucky.

 

[shermanator2]

If truly there is a lot of metal in the gear oil, then it looks like there are two problems here. The squeal is from the vacuum seal as shon in the Arod video, the metal is from something internal. Needs a new front axle assembly plus seal replacement.

 

[Leadmic]

I would go to a 4X4 shop local to you that does a lot of gear changes. Have them change the oil and give their opinion on the front diff and gears. I was a Lead fleet tech for 30 years and as I stated before the limited slip diff oil can be mistaken for having metal contamination if you don't know any better.

 

[NL-Tremor]

Fine shavings in the oil is fine. Chunks of bearing or chips off the ring and pinion are more of a problem. Its highly, highly unlikely to be a diff problem unless you spend considerable time in 4wd. The driveshaft isnt spinning unless its in 4hi or low

Just curious on this one - aren't the driveshaft and diff always turning in these trucks? It was my understanding that we just disconnect at the hubs, not at the transfer case?

 

[Skibum1681]

Just curious on this one - aren't the driveshaft and diff always turning in these trucks? It was my understanding that we just disconnect at the hubs, not at the transfer case?

When in 2wd the t-case is not sending power to the front diff, otherwise, simply putting our hubs in "lock" would put us in 4wd, this is not the case.