Plastic Oil Pans, Valve Covers, Misc. Parts

Shel_B

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What is the reason and intent for using these plastic parts? Is it cost, weight saving, manufacturing ease, strength and durability? How durable are these parts? Have they been used for a while with good results?

The Care Care Nut, a Toyota tech, expects that the plastic valve covers on some of the new Toyota models will be a wear item, needing replacement at about 100,00 miles.
 
When an uneducated tech, who hasn’t ever been an engineer, tells you that composites won’t hold up under stress, show him this picture of a composite structure that has been in service for decades.
C8BA200D-17BE-4556-A300-E216DCE9B546.jpeg

Salt water, extreme heat, extreme cold, G loading, carrier landing, catapult shots, all carried and endured by an airframe that is composite at its core.
 
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Nothing inherently wrong with plastics. Good time in the sentence to say IF they were designed/engineered to last....But that would be incorrect. With the use of CAD a manufacturer can make a part with qualities meant to last to a specific point. Out of warranty, 100k, etc...
 
Seriously, how long ago did you see your first immeasurably strong...............composite milk crate (for Heaven's sake)?

I said to myself, "They'll be making EVERYTHING out of this stuff!" Also seriously: I want the promised, one piece composite tire-wheel.
 
Ford has been using plastic valve covers since at least 1991 on the modular V8s.

I think composite oil pans are a great idea! Metal oil pans rust out. Composite does not. Composite holds up better against impacts than aluminum.
 
What is the reason and intent for using these plastic parts? Is it cost, weight saving, manufacturing ease, strength and durability? How durable are these parts? Have they been used for a while with good results?

The Care Care Nut, a Toyota tech, expects that the plastic valve covers on some of the new Toyota models will be a wear item, needing replacement at about 100,00 miles.

Response to statement 1: Yes to all minus durability. Plastics allow a LOT of flexibility with regards to the design of a part. Durability depends on the frequency and degree of heat cycling. Plastic parts have been used for decades with various degrees of success.

The YT-vlogger (assuming) is probably correct. They're more likely to develop a hairline crack but again it depends on engine power, how hot (i.e. efficient) the engine is tuned to run and the amount of air circulation within the engine bay. The VC on a typical econobox engine will probably last well beyond 100k miles.
 
CAFE standard not only influenced the use of lubricants with lower viscosity and HTHS but also challenged automotive engineers to come up with solutions to reduce weight which also contributes to higher average fuel economy. The increased use of lightweight heat resistant plastics under the hood is one example.
 
How durable are these parts? Have they been used for a while with good results?

The Care Care Nut, a Toyota tech, expects that the plastic valve covers on some of the new Toyota models will be a wear item, needing replacement at about 100,00 miles.
Scotty Kilmer hates plastic car pats too.
Not Durable.
Plastic parts on radiators is normally the failure point. Same with coolant elbows and water pump impellers, and thermostat housings.
That and metal parts don't get brittle with age and fall apart.
 
Scotty Kilmer hates plastic car pats too.
Not Durable.
Plastic parts on radiators is normally the failure point. Same with coolant elbows and water pump impellers, and thermostat housings.
That and metal parts don't get brittle with age and fall apart.
I've had a couple of plastic coolant elbows start leaking on my 3.8 Buick, replaced with metal.
OTOH, the plastic oil filter housing on my Camry has been quite durable, although I am considering an aluminum replacement.
 
composite valve covers were a miracle for noise reduction and have excellent durability/longevity

magnesium was once the go-to for premium valve covers and proved to be problematic and fragile at best
 
Scotty Kilmer hates plastic car pats too.
Not Durable.
Plastic parts on radiators is normally the failure point. Same with coolant elbows and water pump impellers, and thermostat housings.
That and metal parts don't get brittle with age and fall apart.
Mercedes, BMW, VW have been using plastic tanks on the OE Behr radiators for 40 years and more, I have seen them still okay at 20 years and more leak free. Front end collisions even minor ones can twist the radiator and can cause it to leak at the tanks but brass tanks can also spring a leak.
I have a VW with plastic coolant elbows that are original and 22 years old, I will replace them when I do the engine this year. It depends on the material used, BMW has been using recycled plastic for some time and yes they has issues.

What Kilmer thinks is worth next to nothing.

Show me a plastic oil pan that can take this kind of damage:

View attachment 83945
I would remove that pan sooner than later, there is a good chance the pickup/tube is damaged, A plastic one would probably have cracked.
 
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