

⚡ Drive smarter, last longer — the Green Diamond edge.
Hot Shot's Secret Green Diamond 15W-40 is a 100% synthetic diesel engine oil engineered with advanced Group III base oils and patented FR3 nanotechnology. It delivers up to 3% improved fuel economy, reduces engine wear by 71%, and maintains superior viscosity for heavy-duty diesel engines, making it the go-to choice for professionals demanding peak performance and longevity.
| ASIN | B082YFQQ25 |
| Best Sellers Rank | #52,410 in Automotive ( See Top 100 in Automotive ) #414 in Motor Oils |
| Brand | Hot Shot's Secret |
| Customer Reviews | 4.7 4.7 out of 5 stars (164) |
| Date First Available | February 6, 2019 |
| Item Weight | 7.5 pounds |
| Item model number | GDGALFULL-SYN1540 |
| Manufacturer | Hot Shot's Secret |
| Manufacturer Part Number | DIAMOND OIL FLEET:GDGALFULL-SYN1540 |
| Model | Green Diamond 100 Percent Synthetic 15W40 Oil Diesel 1 Gallon |
| Package Dimensions | 11.34 x 8.35 x 4.69 inches |
| SAE J300 Viscosity Grade | 15W-40 |
| Size | 1 Gallon |
| UPC | 731717961482 |
| Vehicle Service Type | Diesel engine heavy equipment, Diesel engine pickups, Diesel engine semis, Diesel engine tractors |
| Viscosity | 15W-40 |
C**H
Top quality oil
One of the higher quality oils available. Price is higher than most, but your getting a oil with tested and tried additives. I use Hot Shots oils and additives in all my vehicles.
R**R
Value for money
Very good product. Ive been a hot shot secret fan for a while. Highly recommend
C**R
Great product
I have a LLY Duramax with 265k miles have been running rotella T6 full synthetic along with Hot shots Stiction additive which made a big difference engine was overall quieter ,I was getting 18 MPG originally, with Hot shots oil I started getting 22 MPG @ 70 mph and 33" tires. Better throttle response, runs better, starts better in the cold I will be using their product from now on.
A**E
Great Oil
This is usually my go to oil. If you have the oil kits that take a small amount of oil and filters it to a lower micron, then it might be worth going with blue diamond, however I have the stock setup so I go with this. After months of hard hauling and off-road I drained out the oil and checked it, there’s a simple test you can do to see if the oil was still good, and after 14,000 miles the oil still appeared to have its additive package mostly intact and viscosity seemed like it hadn’t changed. It’s hard to tell without doing an actual oil analysis in a lab so don’t take my word for it. Keep in mind it’s a gallon, so you may need to buy more containers the. You would from other brands that are 5 quarts, but it’s good to have left over oil incase you need to top off. I feel like my engine runs better in this than Valvoline but that is just subjective and there no way for me to prove that at this time. Customer Service from hotshot is also very helpful if and when you give them a call.
C**R
Its synthetic oil
I have tried a few different types of oil in my 2017 Cummins 6.7 over the years. My RAM is still emissions compliant (unfortunately). I have tried Rotella T6, RP, Amsoil, Valvoline, Regular dealership conventional, and now this stuff. I did not send my oil out for a test before I switched to HSS. I am only going off my driving experience and what it sounds like. After I did the drain and fill and started it up it sounded just about the same as the Amsoil I drained out. It did hold a higher Oil pressure though, but that could also be because the Amsoil had 15k miles and was a year old. But after a couple of hot cycles, it does seem to idle a bit quieter. Fuel mileage remained the same (but I wasn't expecting it to change). One thing I read online is that because they run an additive packet with high....Zink, I believe, it ruins catalytic converters. I am secretly hoping that is true, because I have what I need to "fix" that problem. The smell of the emissions exhaust now is much more pungent and annoying now, so the claim of having more additive of some kind is likely true. Still runs about the same temp (199-210F) when driving empty or towing. Overall, for the price, I will probably go with it again, or Rotella T6 (my engine seems to like either of those with an RP filter)
T**H
Only oil I use
I have a 2002 Silverado 2500HD with about 395k miles on her. I have used a number of different brands of oil over the years. For the past two years, this has been the only oil I use. I do a lot of towing, and often have extended oil changes. It performs just as well as when I put it in. The first time using this, the engine ran much quieter. I can't say much for the mileage claims as I often have varying loads that offer different mileage. The claims that this oil stands up to the abuse are actually true.
R**H
It's powered by science I'm not a scientist it seems to be working
It's been about 3,500 miles my truck is not broke so it seems to be working I don't have any complaints it tastes the same it's oil so it seems to work and it was cheaper than Shell Rotella full synthetic I use their other products trucks got three hundred and eighty-six thousand miles on it it's still going
B**D
Actual shocking how good it works
Legit stuff right here. Literally can’t believe how different it made my lly run. Actually feels like I gained a lot of horsepower running it. Very smooth and overall quality oil. Worth the extra few bucks. At least every once and awhile
Trustpilot
2 months ago
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