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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQT-EA

4.9 star rating Read 1,544 reviews

Customer Rating

4.9

92% would recommend

  • 5 1479
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,544 reviews
  • 5 star rating
    Best products
    By  MAC ,  a  Verified Buyer  from  Utah  on  September 01, 2021
    I only use Amsoil in all my stuff. I have had motors so hot from loss of coolant that exhaust is red hot. With no damage to motor where another lubricated with standard oil would have cam and rod bearing failure. These oils continue to lubricate. They have saved me many times.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quality Product
    By  Greg,  a  Verified Buyer  from  NC  on  September 01, 2021
    Have used Amsoil for all of my diesal oil needs, oil filter and fuel filter. Have always had great performance from Amsoil, more expensive than most but you get what you pay for. My brother-in-law is a diesal mechanic and states beyond any shadow of a doubt it's the best on the market. Will continue to be an Amsoil customer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  PAUL,  a  Verified Buyer  from  Edinboro, Pa  on  September 01, 2021
    Great product, easy to order and quick delivery. Would recommend it to anyone with a deisel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil and filters
    By  FRANK,  a  Verified Buyer  from  Greeley Penn  on  September 01, 2021
    Very satisfied , been using for over 15 years on 1999 Ford F-350 7.3 diesel
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome
    By  TYLER,  a  Verified Buyer  from  Oregon  on  August 31, 2021
    I am a subscriber to Greg Alberalla’s YouTube channel. He speaks very highly of Amsoil products and always seems to do his research before using a product. I did some research on Amsoil and it’s a no brainer. I will only be using Amsoil products from here forward. I wish you guys made a substitute to bw 44-44 for my 4th gen Ram 2500 transfer case. Keep up the good work
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product!
    By  CHARLES,  a  Verified Buyer  from  San Antonio,TX  on  August 31, 2021
    I have a 6.0 with 260K and I’ve been using this since I got it at 130K and this oil makes a difference. Engine is quieter EOT is lower and when I drain it the oil is still good. I started using noting but Amsoil since 2003 when I did a dump compilation with my Harley and one second day of competition I switched and the bike made more HP and TQ and ran cooler. If you’ve ever seen a three ball friction test it will show you this stuff works. Worth every penny. Pay me now or pay me later. It is cheap insurance!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil everthing
    By  BRANDON,  a  Verified Buyer  from  Az  on  August 31, 2021
    Great products! Run nothing but amsoil in my 03 Dodge , love there oil’s packages fast shipping won’t use nothing else!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel Oil
    By  MICHAEL,  a  Verified Buyer  from  Nevada  on  August 31, 2021
    I’ve used AMSOIL for 20+ years and this signature diesel oil is the best money can buy period.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Like
    By  DAVID,  a  Verified Buyer  from  Celeste TX  on  August 30, 2021
    I really like your products I use them in my pick up truck my motorcycle and my lawn mower. I wish I could just go and pick it up
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    15-40w
    By  Frank,  a  Verified Buyer  from  CA  on  August 30, 2021
    Oil arrived very quickly and well packaged.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil!!!
    By  DANNY,  a  Verified Buyer  from  Ms  on  August 30, 2021
    I’ve been running Amsoil in all my Diesel trucks/cars (actually all my engines)for about 10yrs. Put the dual filter bypass systems on my trucks and run everything 15-25k miles, never a problem and they run better than the day I bought them.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Brand for Maintenance EVER WILL BE ON THE MARKET!
    By  JEREMY,  a  Verified Buyer  from  Cullman, AL  on  August 30, 2021
    All I use in my diesel trucks. Have never had a problem with buying high grade oil and other maintenance items from Amsoil. I run Amsoil in everything I own.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  Michael,  a  Verified Buyer  from  Alabama  on  August 29, 2021
    I have switched to Amsoil in my Dodge with a Cummings diesel. I have extended oil changes to the recommended mileage to change oil per the owners manual, as I had always changed before at 5000 miles. I am getting better fuel mileage with Amsoil, and the idle seems to have increased, maybe from less friction? Better Mileage and maybe less wear, that is money in my pocket.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Update on recent review.
    By  LEROY,  a  Verified Buyer  from  Florida  on  August 28, 2021
    I just reviewed this product, but I forgot to add that this oil is holding up to my towing an RV that is at the capacity of My GMC 2500hd Sierra. Just put 7000 miles towing and did not use a drop of oil and the oil pressure remains great.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Heavy Duty
    By  VINCENT,  a  Verified Buyer  from  Florida   on  August 28, 2021
    I have been using Amsoil for about 10 years. It has never failed to protect my investment. I drive a lot so it is important to not have to worry about my oil. Just added bypass to my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  MATT,  a  Verified Buyer  from  North dakota   on  August 26, 2021
    Truck runs smoother no ticks and has easier start ups in the harsh winter up here than truck manufacturer oil when truck was brand new
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great diesel oil
    By  MATT,  a  Verified Buyer  on  August 26, 2021
    I’ve been using this oil in my 5.9 Cummins for about 5 years now. It runs like a champ.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  GEORGE,  a  Verified Buyer  from  California  on  August 22, 2021
    I use this oil in my 2015 duramax. The truck has a load every mile its driven. I carry around 2200 lbs in the bed worth of welding equipment, and when it comes time to go on vacation, there's another 8k on a trailer behind the truck. I'm pretty happy with how the oil stands up to this use. I occasionally take a sample when it comes time to do an oil change. Blackstone labs tell me I need to take the oil to 10k miles, due to the cleanliness and abundance of additives sill remaining. I'm hesitant to take it past 8500 miles though, due to being raised on the 3750 mile oil change interval taught by my dad!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome product
    By  RICK,  a  Verified Buyer  on  August 21, 2021
    I like using amsoil product’s
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil
    By  AJ,  a  Verified Buyer  from  Erath La.  on  August 21, 2021
    Ordered oil came in fast! I have been and will use this oil for the life of my engine hopefully it will last a lifetime
    Bottom Line
    Yes, I would recommend this to a friend.
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