Promolyze is reader-supported. As an Amazon Associate we earn from qualifying purchases — at no extra cost to you.
Hot Shot's Secret Diesel Extreme - Deal
Price as of June 16, 2026 — check Amazon for the current price.
Get This Deal →- ✓ Secure checkout on Amazon
- ✓ Fast shipping
- ✓ Price may change anytime
By Patrick Smith · Updated July 10, 2026 · How we review
Hot Shot's Secret Diesel Extreme is the periodic deep-clean in the company's lineup — a concentrated injector cleaner and cetane improver you dose into a full tank a few times a year, as opposed to Everyday Diesel Treatment (EDT), which owners run in every fill. That distinction matters, because diesel forums are full of people using the wrong one for their goal. The reports from long-running owner threads are genuinely mixed in an informative way: many describe smoother idle, better throttle response and visibly less black smoke within the treated tank, while some multi-year users concede they never measured a fuel-economy change and can't rule out placebo. A common owner practice is running it through a tank just before an oil change, since dislodged deposits end up in the fuel system and combustion process. It's cheap insurance for high-mileage engines on inconsistent fuel; it is not a repair in a bottle.
Our verdict
A reasonable periodic clean for higher-mileage diesels or trucks running variable-quality fuel; skip the expectations of measurable MPG gains, and use EDT instead if you want an every-tank additive.
Sources & further reading
What buyers say
Our summary of recurring themes in customer reviews on the Hot Shot's Secret Diesel Extreme Amazon listing (read July 2026) — not quotes or endorsements.
Most praised
Diesel owners on enthusiast forums most often report smoother idle, cleaner acceleration and noticeably less black smoke after running a treated tank.
Most common complaint
The recurring counterpoint is that results are hard to verify — some long-term users report no fuel-economy improvement and openly wonder whether the felt benefits are placebo.
Worked best for
It worked best for higher-mileage diesels and trucks on inconsistent fuel; owners wanting continuous protection tended to prefer the every-tank EDT product instead.
Why buy the Hot Shot's?
- Cleans diesel injectors and fuel system deposits.
- Boosts cetane for improved combustion during the treatment.
- A periodic deep-clean dose, not an every-tank additive.
Hand-picked deal
One of our top trending picks in Auto & Tools.
Live best price
We link straight to Amazon so you always see today's real price.
Fast shipping
Fulfilled by Amazon — fast, often Prime, delivery.
Easy returns
Backed by Amazon's secure checkout and return policy.
Was $19.53 — prices change fast on Amazon
Price as of June 16, 2026. Tap to see the current price.
The Hot Shot's Secret Diesel Extreme is one of the Auto & Tools deals worth grabbing right now.
Hot Shot's Secret Diesel Extreme - Deal
Give a hard-working diesel a deep clean — one treated tank targets injector deposits, rough idle and smoke.
Hot Shot's Secret Diesel Extreme at a glance
- Product
- Secret Diesel Extreme
- Brand
- Hot Shot's
- Category
- Auto & Tools
- Price
- $19.53 (as of June 16, 2026)
- Availability
- In stock on Amazon
- Condition
- New
- Shipping
- Fast, often Prime
- Returns
- Amazon return policy
The Promolyze promise on every pick
Quality you can check
Why trust these picks
Secure and simple
The Hot Shot's Secret Diesel Extreme won't stay at this price forever.
You May Also Like
- 🔥 Trending
HOTO 40-Piece Household Tool Kit$64.99View → - Fan favorite
HOTO Cordless Electric Screwdriver$29.99View → - 🔥 Trending
JOREST Car Fuse Assortment Kit$13.99View → - Popular pick
JOYROOM Motorcycle Phone Mount$15.99View → - Hot deal
Kaistyle MagSafe Car Phone Mount$9.98View → - 🔥 Trending
Kidde FA110 Multipurpose Fire Extinguisher$39.70View → - Hot deal
KMM Handheld Car Vacuum$29.99View → - Fan favorite
KUST Semi-Truck Side Window Sunshades (2-Pack)$28.88View → - Top pick
KUST Tesla Windshield Sun Shade$16.99View → - Top pick
Lamicall Bike Phone Mount$15.99View →
More from Hot
Frequently asked questions
How often should I run Diesel Extreme?
It's positioned as a periodic deep clean rather than an every-tank additive — many owners run it a couple of times a year, often through a full tank shortly before an oil change. For every-fill dosing, Hot Shot's sells Everyday Diesel Treatment (EDT) instead.
Will it improve my fuel economy?
Don't count on it. Forum reports are mixed: smoother idle and reduced smoke come up frequently, but several long-term users say they never measured an MPG change. Cleaning benefits appear more consistent than economy gains.
Is it safe for modern common-rail diesels?
The product is marketed for all diesel engines, and forum users run it in everything from older Cummins trucks to modern European common-rail diesels. Follow the dosing on the bottle and treat a full tank rather than overconcentrating in a partial one.
Hot Shot's
$19.53