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Gear Tooth Failures #5076722 04/16/19 11:17 AM
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MolaKule Offline OP
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There are a number of causes of Gear tooth failures, but the most common one is due to, "Pitting."

Please complete the sentence;

Pitting is primarily due to............................................................................................................



This question is not open to any engineering discipline, but is open to everyone else.


Last edited by MolaKule; 04/16/19 11:18 AM.

"Dr. Larry Fleinhardt:
You know that it's considered unsolvable?
Charlie Eppes:
Well, certainly people who have failed to solve it might think that." From NUMB3RS
Re: Gear Tooth Failures [Re: MolaKule] #5076727 04/16/19 11:20 AM
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spasm3 Offline
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I'm going to say, water intrusion into the differential.



13 elantra 78k 5w30 synpwr
03 chevy avalanche 83k synpwr 5w30
17 mazda cx-5 16400 miles m1 0w40
Re: Gear Tooth Failures [Re: MolaKule] #5076755 04/16/19 11:55 AM
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Inspecktor Offline
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air bubbles in lube collapsing, causing small areas of metal to metal contact and wear.


2001 Ranger 3.0 177,500 mi
2006 Dakota 4.7 156,000 mi
1986 GL1200A 74,500 mi
2001 Buick LeSabre Limited 297,000 mi
Re: Gear Tooth Failures [Re: MolaKule] #5076761 04/16/19 12:02 PM
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Reddy45 Online Content
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Cavitation?

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076778 04/16/19 12:24 PM
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wwillson Offline
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contact stress exceeding the surface fatigue strength

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076813 04/16/19 01:12 PM
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vw7674 Offline
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Long-term lube contamination.

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076822 04/16/19 01:24 PM
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oldoak2000 Offline
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low oil level!

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076826 04/16/19 01:29 PM
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NoNameJoe Offline
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Cavitation is proven to literally eat away at submarine propellers so I would say that.

I also think a potential cause is additives interacting with the metals? I remember hearing somewhere that certain additives (maybe limited slip? sulphur-based?) could destroy rack and pinion gears made of yellow metals like brass?


2015 Civic LX Coupe
(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076827 04/16/19 01:29 PM
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gman2304 Offline
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Heat/fatigue.

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076853 04/16/19 01:53 PM
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RDY4WAR Online Content
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I'm going to say pitting is primarily due to insufficient film thickness for the load on the gears.


"He who is without oil, shall throw the first rod." - Compressions 9:1
(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076869 04/16/19 02:06 PM
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barryh Offline
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It's surface fatigue from cyclic loads.


Barry

1979 BMW R45 (Triple QX 5W40)
2009 Mercedes C180K (MB oil 229.5 5W40)
(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076887 04/16/19 02:24 PM
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EdwardC Offline
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poor maintenance! smile

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076925 04/16/19 02:58 PM
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CT8 Offline
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Extreme loading or water in the lube or the wrong lube.

(NA) Re: Gear Tooth Failures [Re: MolaKule] #5076931 04/16/19 03:03 PM
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javacontour Offline
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Oxidation of the lubricant, leading to corrosion on the gear.


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(NA) Re: Gear Tooth Failures [Re: wwillson] #5077097 04/16/19 06:09 PM
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IndyIan Offline
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Originally Posted by wwillson
contact stress exceeding the surface fatigue strength

+1


07 Focus ZXW, 5spd manual, 245km M1 5W30
18 Outback 2.5 CVT 35km 0W20
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