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ARP 400-8504 High Performance Hardened Washers 2-Piece

Manufacturer

Picture for manufacturer ARP

Part Number

400-8504
11 reviews
Sale Price

$4.12

1 left at this price

delivery box

Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

ARP 400-8504 high performance washers are precision-engineered components designed for demanding engine applications. These premium washers are constructed from chrome moly steel and undergo parallel-grinding and heat-treating processes to ensure optimal load distribution and durability under extreme cylinder head clamping loads.

Key Features:

  • Chrome moly construction for superior strength and fatigue resistance
  • Parallel-ground surfaces ensure even load distribution across fastener heads
  • Hardened and heat-treated for maximum durability
  • Black oxide finish provides corrosion resistance
  • No chamfer design on inside diameter
  • Precision-manufactured to ARP's exacting tolerances

Package Contents:

  • 2 washers per package

ARP washers are essential components when installing high-performance cylinder head fasteners. The parallel-ground surfaces and hardened construction prevent washer deformation under high clamping loads, ensuring consistent torque values and preventing embedment into softer materials. These washers are ideal for racing applications, performance rebuilds, and any engine assembly where precise fastener loading is critical.

Products specifications

Hardened

Yes

Inside Diameter Chamfer

No

Quantity

Sold as a pair.

Size (ID/OD)

3/8 / 0.72

Thickness

.120?

Washer Finish

Natural

Washer Inside Diameter (in)

0.375 in.

Washer Inside Diameter (mm)

9.525 mm

Washer Material

Stainless steel

Washer Outside Diameter (in)

0.720 in.

Washer Outside Diameter (mm)

18.288 mm

Washer Thickness (in)

0.120 in.

Washer Thickness (mm)

3.048 mm

Great prices. Great live customer service. Very pleased, will definitely order again.

Very great to deal with. Phone support is amazing!<br><br>Thanks,<br><br>Chad

I got the part I ordered and will be having someone install it soon looks just fine and I love the chat feature as well.. thinking about buying brake shoes now.. a lot of savings

cheapest prices around!!!!!!!!!!!

I ordered a new battery for my Harley. I wanted a battery that would last and be of good quality. I bought a Odyssey PC545 battery it stats stat it will last up to 8 years and is military grade. My package arrived quick and in good shape. My order number is #5600. Thanks

Autoplicity created a great shopping experience. It was very easy to find the parts I needed for the vehicle I needed. I will definitely use Autoplicity again!

I'll admit to being skeptical at first, but the price was worth the risk. Turned out to be one of the best online transactions I've experienced. Received item 3 days after purchaseing and the best price I found. And I looked hard! A+

Have to say I made a mistake about these guys they get the stuff shipped out quick.

Could not find the part I was looking for at any other 4x4 website. Found it here and it was cheaper than almost every other place. Since I saved some I went ahead and paid the extra for 2-day shipping and still came out on top price wise. Definitely will be checking here again for parts for my Jeep!

great prices and customer service was very helpful.

Great seller, answered my questions and offered discounted shipping. Will buy from again!

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