Power divider help

[greerco]

Hi, So today one of my good customers came to see me. Story is on 24-07-16 i did a safety on his dump truck. At that time i repaired a crack in the rear cover of the power divider. (it was leaking at the cover weld) On 15-10-16 (almost 3 months later) i got a call that his power divider was red hot. The lower shaft front bearing had cooked. (all other parts looked great except for the obvious metal shavings in residual oil left in the hubs and tubes. I went to drain the differential before removing it and there was little oil in it. Less than a liter. So i removed the diff and put another in....so today he comes to see me and questions weather i put oil in the differential after i welded it back july. The truck had driven 12000 plus kilometers since i welded it with out any issue. I remember clear as day filling the differential with oil after i welded the cover months ago and it had been going without leaks or issues. This is a good customer of mine. Any suggestions. Just a fyi there was no trace of a leak on the truck and the truck runs every day. I swear its like somebody drained it.. Not me.....

I've been doing this for many years. Years ago i had a apprentice forget to fill a diff and it didn't last 100kms...let alone 12000...
If there was no oil in the diff how did the metal filings get into the hub bearings on both sides? .

Im at a loss of for what to think..

Any thoughts?

 

[Truck Shop]

That's a sticky problem, If their the good customer you say then you can hash it out with them over what is fair. If they get pissy about it well you know where I'm going.
But on outside work in our shop {drain plugs and fill plugs are marked with a paint pen and the fact it was filled is initialed by a second mechanic on the work order].

Truck Shop

 

[RZucker]

I've seen drain plugs with boogered threads that felt tight and were packed with Teflon tape that would drip only when the oil was hot. Parked on gravel you'll hardly notice a leak. Had a customer the lost 30 gallons of 90wt from a scraper diff left sitting for 8 months in sandy soil, the oil didn't show til you started digging. But it had a hairline crack in the sump.
Regarding leaky truck drain plugs... the usual culprit is a 10 ton floor jack that mushrooms part of the plug so it feels tight, but it's not. Or chips in the threads, that's a good one with magnetic plugs.

 

[lantraxco]

Clue for me is that the lower shaft bearing cooked? Seems like if she ran low on oil for a long time, something in the upper end would have gone first, even with the ring gear throwing oil?

 

[greerco]

I just spoke with the very reputable power train shop here in Ottawa, the people who rebuilt the actual power divider. He confirmed that lack of oil wasn't the cause of the diff to let go. He said that when there's no oil in a power divider the first bearing to go is almost 99% of the time the input bearing and or all the far top bearings. The only bearing that failed was the lower idler bearing.

This is strange...... and a huge lesson on marking and checking oil levels and caps. I hope I can resolve this with my customer, he a good customer and i don't want to loose him.

Thanks for all the help folks!

 

[kenh]

If the customer has any intellect he should be able to comprehend the statement form the rebuild shop!