"Fits and seals great!"
Cummins
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WrenchConnected is an independent installation marketplace operating in partnership with Diesel Power Products.
After checkout, we route your vehicle info and part SKU to verified installation shops near you. Local installers review the job and submit competitive bids; you pick the shop you want based on price, reviews, and availability. Your name and email stay private until you select an installer.
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Sinister stands for everything diesel and they have made a name for themselves manufacturing some of the highest quality diesel engine components in the industry. The Sinister Diesel brand was born out of an idea from the founders while working on one of their own trucks. What if they started their own diesel performance business manufacturing and selling high quality air intake, fuel, and engine components? That idea transpired into the Sinisterl Diesel we know today. In order to make sure that when you popped the hood, you could easily distinguish a œSinister branded part from other companies, nearly everything they manufacture is coated in their trademarked œSinister Blue. Whether you drive a Cummins, Powerstroke, or Duramax, they can outfit your entire truck with cold air intakes, fuel tank sumps, oil filtration, regulated fuel return kits, and so much more. If you're looking for quality performance parts at a great price, look no further than Sinister!
Overall rating: 3.125 / 5 from 8 reviews.
Review topics: ["fit","looks","seal"].
"Fits and seals great!"
"Very loose fit. It has a big o-ring but does not seal the hole like I expected"
"This cap fits nicely on my Ram 2500 and the best part, its American Made."
"Sinister always live up to the quality I am accustomed to, I love Sinister products."
"Blew off first trip out. I have my bed off so no fuel door. Didn't fit well enough to stay looks cool but in the end I might as well thru the money out the window"
"Looks great and a good idea, but claims to seal better than the plastic factory cap, mine does not. I was looking for a better seal and not for looks."
"Works perfect."
"I have this 2 stars because it looks awesome and feels like a quality piece but it is waaaaay too small. Also the box I was sent said it fits 13-17 not up to 21. Buyer beware."
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