Ever wonder why hypoid gear oil stinks so bad? Most of us simply accept the fact that gear oil stinks and grudgingly anticipate the horrid smell when we service a drive axle assembly as a necessary evil.
Ring and pinion assemblies feature gears that mesh together creating enormous pressures that push the lubricant out between the gears. If even momentary lubrication is lost and we have metal-to-metal contact, the contact points transfer metal, elevating heat and wearing the surfaces, eventually to the point of gear fracture.
To avoid this, and to maintain a lubricity film between the gears at the maximum pressure point, an extreme pressure (EP) additive is used in the lubricant formula, usually involving sulfur and/or phosphorous. That’s what makes the lube so smelly.
To make the state of stink even worse, a friction modifier (often specified by the automaker) is added to the already stinky oil, raising the skunky-ness to an even more horrific nasal-assaulting level.
These high pressure additives provide a 1-2 micron-thick lubricity between the contact points that protect the gear from wear. So, even though we may despise the odor, and quite often work shirts must be tossed in the trash because we don’t want to bring the stink home with us, we need what the lube provides.
Personally, I kind of like the airborne signature, especially after everything is buttoned up and filled. It smells like victory.
Over the years, I was constantly paranoid about placing any electronic device, such as my smartphone, in close proximity to a magnet. For instance, when using a magnetic tray underhood to secure tools, bolts, nuts, etc., I was afraid to rest my cell phone on the tray for fear of messing up the phone, losing data, etc.
Well, I guess I was wrong. Apparently, a magnetic field next to your smartphone won’t cause any damage (unless the magnet is strong enough to lift a car, that is).
According to the research I did, the smartphone makers designed their toys to prevent operational problems caused by a light- to medium-strength magnet.
Of course, the exception might involve an inaccurate reading with a compass application, but apparently exposure to a nearby magnet won’t cause a malfunction or cause you to lose stored data. Magnets apparently will not damage a CD, DVD or a flash drive... something I’m relieved to learn.
Just mentioning some of the many things I’ve been wrong about. I’m sure there are more to come.
I have deactivated hotel room key cards by placing them in the same pocket with my cell phone, but that’s a different story.
At least now I know that I can rest my smartphone on or near a magnetic tool tray without freaking out. ■
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