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What ages besides oil ??

346 Views 15 Replies 13 Participants Last post by  Jaxworx
Much talk about how many miles before changing something, but what about just age?? If you have an old car with few miles are'nt there some things that just age?? I had the 30K mileage done at dealer under my maint program. I had to pay for some of the fluid changes as they are "recommended" but " not covered". Anyway I got all the fluids changed. The Michelin Premier A/S tires are date coded 1014, but still stick like glue when you push hard in the corners. What car parts age besides oil???
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I do. And the harder you push, the more I stick.
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There are different reasons why various fluids age.

For motor oil, few miles can mean that moisture sits in the oil causing it to acidify and do other bad stuff to it that has nothing to do with mechanical shear. There are devices in commercial trucks that purposely heat up oil to purge moisture and other contaminants like fuel that makes its way into the oil, making it deteriorate.

For brake fluid, DOT3, 4, 5.1 are hydroscopic, meaning that they absorb water, and as they absorb water their boiling point decreases, and it can also potentially cause corrosion in the brake system. High humidity accelerates this in brake fluid.

Tires age with time - they oxidize and the rubber becomes less elastic, the rubber can harden and crack, so based on age alone, tires should be replaced between 6 to 10 years.

Similarly, rubber hoses, bushings, can deteriorate with age.
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Much talk about how many miles before changing something, but what about just age??
Good questions!
First of all ... OIL DOES NOT AGE... it has been in the ground for MILLIONS of years and has aged-out long ago.

However, the ADDITIVES get depleted as the metal parts rub the oil. Additionally, contaminants build up within the oil.

You are correct that there is more than "age".... there is also heat/cold, condensation and other factors involved. I have listed some items below from memory... I am sure there are others.

For example: ALL gearcases (including engine crankcase) must be vented to prevent pressure build-up.
However, this also means humidity in the air gets sucked into the vent. When the ambient temperature gets cold, that moisture condenses and ends up as water-droplets at bottom of gearcase. (water is heavier than oil)
Over the course of 100s of heat/cold cycles, there can be several cups of water sitting in gearcases.

Battery life is affected due to ambient temperatures. Infact.... batteries sold in Arizona (heat) are DIFFERENT than those sold in the NorthEast where it is colder. The internal-structure of the plates is different.

Brake Fluid is hygroscopic and absorbs moisture from the air. This is done ON PURPOSE for reasons I will not get into here. What it does mean is that Brake Fluid should be replaced based SOLELY on age (not miles) every 3-5 years.

The rubber within tires ages and should be replaced every 7 or so years NO MATTER WHAT THE TREADS LOOK LIKE.

Plastic chain-guides within an engine will eventually fail due to being soaked in hot oil for 10000s of miles. This is a VERY common failure-mode on older engines with timing-chains across ALL automakers.

If you have an old car with few miles are'nt there some things that just age??
Rubbers, Plastics and some fluids this includes:
  • Belts
  • Seals
  • gaskets
  • plastic chain guides
  • tires
  • Antifreeze
  • Brake Fluid
  • etc

What car parts age besides oil???
(Answered above)
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I would add: radiator hoses to the list. Tires are easy to inspect for cracks between the treads, but old radiator hoses may look good on the outside, yet fail.
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A word of a joke, don't kill me :
We also age but nothing to do about it except for going to the human mechanic called Dr. Somthing and obey his orders regarding food and sport.

Now to the OBk.
Plastics parts including those new radiators hosing connection points.
Metal moving parts due to rubbing, loads, bearing.
Metal due to rust in cold, sea areas.
In short, every single part of the car ages...eventually.
Tires depend on location. We are in the Midwest USA and run a large fleet and the tire replacement is 10 years unless it’s a very expensive tire on an asset that doesn’t get used much and then it will go much longer, but I’ve heard out in the desert areas like Arizona rubber degrades quicker
Tires depend on location.
Agreed... LOCATION dictates the speed of "aging" :)

Here in Vermont, the winter road-salt gets into EVERY nook-n-cranny of our vehicles. Then, the humid summer arrives and the dried salt hiding in the crevices of our cars 'wakes up' and the corrosion begins. This slow rot of our cars only ends with the next winter where MORE salt is added.

After about 10 winters, the vehicle fails the state-mandated safety inspection and must be replaced.

I have visited states like Colorado and observed WallyMart parking lots are FULL of 20 year old cars. This is where the age of the tires matters :)
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I just replaced all rad hoses, including the hard pipes underneath the engine. While I was there, I replaced the thermostat and rad cap with OEM items.

Overheating is the one thing guaranteed to kill a Subaru. Inspect and maintain your cooling system.
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Everything but the windows.
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Everything but the windows.
Little known fact.... Glass is often considered a supercooled FLUID (amorphous solid) which is always flowing down due to gravity.

My 150+ year old house is a great example. The original glass panes are slightly thicker on the bottom than on the top.
Anyone who pays attention when in an old building will notice this phenomenon.

There a not a lot of vehicles which make it to 150+ years old.
150 year old house!?!
I guess the term master bedroom has a special meaning.
I have a 27-year-old BMW. I can guarantee things age out. The latest is the rubber throttle bushings and rubber door handle gaskets. My last tires aged out last year. However, the ABS brakes still have the original brake lines, brake booster, and wheel cylinders. Brake fluid is changed every 2-3 years. Yes, it is now a garage queen after serving well as a commuter car.
Spouses. Third one, both flexible and durable, seems to be holding up better than previous iterations.

Perhaps the technology has improved.
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