Skip to Main Content
Shop by Vehicle

Customer Ratings & Reviews

AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

Product code : DHDQT-EA

4.9 star rating Read 1,537 reviews

Customer Rating

4.9

92% would recommend

  • 5 1472
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,537 reviews
  • 5 star rating
    Got a compliment about your oil
    By  GENE S.,  a  Verified Buyer  from  Lancaster, CA  on  March 27, 2025
    Coming back from a round-trip CA to TX and back, then 60 miles from home had turbo problems on my 2014, RAM 3500, with 61K miles. We use the pickup about 80+ % of the time pulling our fifth wheel trailer. The local RAM dealer did the repairs and made a note on my receipt, that from what they could see, we had an exceptionally clean looking engine interior. Except for my original oil when I got the truck, it's had Amsoil 15W-40 ever since.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best Diesel Oil money can buy!
    By  Tuheeden,  a  Verified Buyer  from  North Carolina, USA  on  March 27, 2025
    Owning and operating a horse park, we have dozens of diesel engines from small to large. Amsoil has become our go-to oil for all our engines. Not only do the engine run quieter, less consumption and we have been able to extend our drain intervals (verified with oil analysis). We even use this for our fun bracket racing engines. Very pleased all the way around.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    review
    By  NEIL,  a  Verified Buyer  from  CA  on  March 24, 2025
    great transaction , great product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    No complaints
    By  ELI,  a  Verified Buyer  on  March 24, 2025
    Oil change every 5k, it’s served me well.
    Bottom Line
    No, I would not recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    5w-40
    By  BRIAN,  a  Verified Buyer  from  Central British Columbia   on  March 18, 2025
    10/10. I have been running this oil in my truck since new. Pushing 300k km and it still doesn’t burn a drop of oil in between services.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Peace of mind
    By  PATRICK,  a  Verified Buyer  on  March 17, 2025
    Keep my business running without a worry
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Use in my Yanmar powered John Deere 2320
    By  KIRK,  a  Verified Buyer  from  ME  on  March 16, 2025
    I never worry about oiling issues with my John Deere 2320. I've put an increasing number of hours on the tractor in recent years which I use for a combination of very hot weather/ conditions pasture mowing, chipping, snow removal and logging. My usage ranges from low speed operation in colder weather to high rpm PTO usage for chipping and pasture mowing. Logging requires a fair amount of idling then low rpm winching and mid rpm heavy pulls and pallet fork usage for stacking logs. I change my oil once a year (50-150 hours depending on the year) I don't abuse the tractor but it's working hard every time that it's running. I worry about breaking parts on it but I never worry about engine lubrication.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Oil
    By  TIMOTHY,  a  Verified Buyer  on  March 15, 2025
    Great product fast shipping
    Was this review helpful?
  • 5 star rating
    Best diesel oil on the market by a mile.
    By  RYAN,  a  Verified Buyer  from  Lookout mountain Georgia   on  March 15, 2025
    Run 35k changes on the cummins running this a amsoil ea080 and the amsoil large bypass system. Last truck got 1.3 million miles on all original cummins 6.7 engine .
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best engine Oil ever
    By  STURE,  a  Verified Buyer  from  MN  on  March 14, 2025
    I am so pleased with this oil for my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    15-40 diesel oil
    By  TONY,  a  Verified Buyer  on  March 14, 2025
    I have used this oil for the last 10 years in a 2015 duramax. I work the truck every day and have 209k miles on the truck. The truck doesn’t use any oil between its 7500 mile oil changes and still runs like new. I recommend giving it a try.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil oil
    By  MICHAEL,  a  Verified Buyer  from  Texas  on  March 14, 2025
    I used Amsoil in the 1980’s back then you had to know someone that sold it. Now we can order it online, it’s costly but I use it until I reach 12000-15000 miles which is usually about a year and a half. I trust the brand. I keep a spare case on hand.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    top notch product
    By  JOHN,  a  Verified Buyer  from  Tampa FL  on  March 13, 2025
    Good clean product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil used in my l5p duramax
    By  ROBERT,  a  Verified Buyer  from  Ohio  on  March 11, 2025
    Great oil , no complaints , it even got rid of the classic duramax type writer tick ! I'll never use another oil in it now that I've used this
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Due for oil change
    By  JONITHAN,  a  Verified Buyer  on  March 10, 2025
    Always a pleasure Pays to be a member for discounts My goto products
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Ram 3500 HO Prefers 5W-40
    By  JASON,  a  Verified Buyer  on  March 09, 2025
    My 3500 Ram HO definitely prefers the 5W-40 over the 10W-30. It runs noticeably smoother and quieter with 5W-40.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The Good Stuff!
    By  ALEX,  a  Verified Buyer  from  Albuquerque  on  March 09, 2025
    My 7.3 diesel loves this stuff!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Long time user
    By  JEFF,  a  Verified Buyer  from  OK  on  March 08, 2025
    Been a long time Preferred Member. This is my first diesel vehicle. I have trusted this oil in my gas engines for 25K change intervals. I will trust this oil in my diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    What Else Would You Use
    By  Whitesheep,  a  Verified Buyer  from  ARIZONA  on  March 08, 2025
    Only the best for my G3 RAM. Original turbo, no oil issues. 125k miles. What is not to like?
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best Product-Best customer service
    By  JUSTIN,  a  Verified Buyer  from  Belledonte,pa  on  March 07, 2025
    Ive been using amsoil almost 30 years and has certainly proven to me that it is everything they say it is..I certainly recomend it. Ive just started ordering directly through amsoil for the 25% discounted price and one of my orders had 2 quarts damaged, took a pic and emailed it and within hours they responded and sent new ones immediately. Couldnt be happier with service! ⭐️⭐️⭐️⭐️⭐️💯
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?