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Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEOQT (DEOQT-CA)
Quart Bottle
Case of 12
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEO1G (DEO1G-EA)
Gallon Jug
Each
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEO1G (DEO1G-CA)
Gallon Jug
Case of 4
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEOTP (DEOTP-EA)
2.5 Gallon Jug
Each
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEOTP (DEOTP-CA)
2.5 Gallon Jug
Case of 2
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEO55 (DEO55-EA)
55 Gallon Drum
Each
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
DEO27 (DEO27-EA)
275 Gallon Tote
Each
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
Signature Series Max-Duty Synthetic Diesel Oil 5W-40
4.9 star rating
Based on 869 reviews
5 star rating
Good oil.
By 
GARY, 
a 
Verified Buyer 
from 
Ft Worth Tx.  
on 
July 06, 2022
Just changed oil in our new Chevy Duramax 3500HD 3000 miles on truck. pulled 33 ft toy hauler to Colorado 1800 miles round trip an used 1/4 quart of oil. Will continue using Amsoil in all my engines.
Bottom Line
Yes, I would recommend this to a friend.
Was this review helpful?
5 star rating
confident
By 
WILLIAM, 
a 
Verified Buyer 
on 
July 04, 2022
i have used amsoil back from the 70's, i use all of these in all my stuff
I`m 70 years old was in the auto repair business for 49 years. involved in racing my whole life an currently drag race a challenger hellcat. I decided to forge the bottom end of the motor an could not believe how good everything looked inside the motor. connecting rod bearings look like they just came out of the box. pistons an cylinder walls are perfect.
but at the same time not all that surprised . always used amsoil an will continue to do so.
Bottom Line
Yes, I would recommend this to a friend.
Was this review helpful?
5 star rating
Great oil
By 
GREG, 
a 
Verified Buyer 
on 
July 01, 2022
The engine runs cooler and smoother with this oil. Plus I get 7500 to 9000 miles between changes.
I run this in all of my diesel equipment (tractor, excavator, ram 5500, generator) and only change once a year regardless of miles/hours. This saves me time and money from having to do multiple changes if running conventional oil.
It also seems to have a much higher retention/suspension capacity for contaminants than other oils.
Bottom Line
Yes, I would recommend this to a friend.
Was this review helpful?
5 star rating
40 year user
By 
ROD, 
a 
Verified Buyer 
on 
June 21, 2022
Been using for 40 yrs. Best of the Best.
Bottom Line
Yes, I would recommend this to a friend.
Was this review helpful?
5 star rating
Purebred Synthetic.
By 
SCOTT, 
a 
Verified Buyer 
from 
SE USA 
on 
June 20, 2022
I am so impressed with the results of the laboratory oil analysis since switching to AMSOIL Signature Synthetic motor oils. AMSOIL is a company with a spine of integrity.
I will always use products I can trust in. Amsoil is at the head of my list!
I have created quite a few converts.
Autos and trucks are usually the second biggest investment in a person's life so DO NOT trust any old oil. I'll stick to this brand so I won't have something else to worry about.
My order always arrive quickly and accurate. However, my last order the warehouse forgot to include my WIX oil filter. I called Amsoil and they sent me one the next day. Great customer service.
Mike
My 2002 Dodge 2500 Has been lubricated with AMSOIL products for about 16 years and over 200,000 miles. I would not use any other product. The 5.9BT has all the power and the running gear is smooth and noise free.
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