Motor Oil for 671 Detroit Diesel

[1951Bus]

Confused about the correct engine oil to use in my 671 Detroit Diesel.  I purchased 6 gallons of 15/40 Rotella T Diesel oil.  I cannot find straight 40 weight.  Is it okay to use what I purchased?

[eagle19952]

Best not too.

[TedCalvert]

I think the book recommends straight 30 or 40 wt., depending on ambient temp.

[dreamscape]

NAPA might have it on the shelf. I saw some the other day here in Seal Rock OR.

You should use straight 40 wt.

[eagle19952]

here's your choices.
Low ash  mono weights:

UNION 76 T5X Heavy Duty 40wt:

76 T5X Heavy Duty 40wt monograde motor oils SAE 30, 40 and 50 meet or exceed the performance requirements of API Service Categories CF-2 and CF, and also may be used in applications where API CD quality oils are specified/designed primarily for use in high-output, 2-stroke cycle diesel engines. They are particularly recommended for use in 2-stroke cycle diesel engines in transit buses and marine fleets running on low-sulfur diesel fuel.



TEXACO URSA® EXTRA DUTY
SAE 30, 40, 50

The SAE 30 and 40 grades are also specifically
recommended for use in two-stroke diesel engines
requiring highly effective control of wear and deposits.
Texaco Ursa Extra Duty oils:
• meet API Service Categories
— CF-2, CD-II1 (SAE 30, 40, 50)
— CF, CD1
• performance requirements of
— Allison C4 Fluids (SAE 30)
• comply with Detroit Diesel Corporation twostroke
engine recommendations, including the
0.85% ash maximum limit for Series 149 engines.



Sulfated Ash Rates:
Chevron Delo 100 40 WT = 0.76 (24% BELOW benchmark)

Exxon XD-3 40 WT = 0.80
TEXACO URSA EXTRA DUTY = 0.85

Citgo Mystik Premium Fleet Engine Oil 40 WT = 0.90

Shell Rotella 40T 40 WT = 1.00 (Shell Rotella 40T is borderline)

Delo 400 40 WT = 1.35 (35% OUT of TOLERANCE)

THIS I AM NOT  SURE ABOUT but i researched it any ways :
AMSOIL Synthetic 10W-30/SAE 30 Heavy Duty Diesel Oil (ACD)
 
AMSOIL ACD is recommended for diesel engines, gasoline engines and other applications that require any of the following worldwide specifications:
• API CI-4+/CH-4/SL, CF, CF-2
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[RJ Long]

Steve -

Best to take the multi-weight back, it's not recommended.  ONLY straight 40wt.

Do you have an O'Reilly's nearby?  If so, Chevron Delo 100 is usually available overnight or w/in a couple of days.  Tell the parts guy to enter the following info into the computer:

Vendor Code: CHV  Part Number (SKU): 100-40-1 

This will get you 1 gallon jugs.  3 gallons/case.  7 gallons needed for an oil/filter change.  Buy three cases and have some left over for touch up.

FWIW & HTH. . .

 

[luvrbus]

You live in FL any marina on the coast will have straight 40w any brand is ok

[buswarrior]

Real life example:

I knew where my coach was being operated in its former life. It had multi-weight oil in it.

I got it with fresh oil, and ran it. Oil consumption was significant, as I have since learned, relative to the age of the engine.

After my own first oil change to straight 40 wt, oil consumption dropped WAY down.

Others have reported similar experiences over the years.

There are also technical reasons to do with proper bearing lubrication with the high loading of the bearings relative to a 4 stroke. In layman's terms, the multi-weight won't stay in the bearing and do the job like a heavier oil will.

For busnut use, run the 40wt, and install whatever engine pre-heat system you have to, to compensate for cold weather starting.

I confidently run 40wt all year 'round and live up here in the nearer north, in relative terms...

happy coaching!
buswarrior

[eagle19952]

WEST MARINE< which is probably the highest price you will pay
DELO 100 Diesel Engine Oil - SAE 40, GA    6865349  222404436 In Stock $23.99< gallon   
DELO 100 Diesel Engine Oil - SAE 40, 5 GA    6865356  222404448 In Stock $119.99< 5 gallon

call this number in tampa they are in orlando too.
 1-800-683-LUBE

[Easy Street]

I just bought two 5 gallon pails of Rotella T 40wt from my Shell oil distributor 2 weeks ago.  It is still in their system, some dealers just don't stock it due to lack of demand. Try another dealer or use another quality brand of oil such as those previously mentioned.

[57GMC]

I go to NAPA and order the Rotella T1 straight 40 weight and it meets the CF-2, CF for the 6-71.
Thanks
Steve

[Scott Crosby]

That delo 100 at o'riley is only $13 and change per gallon for 40 wt.  They order it, and it comes in a day or two.  By far the best deal I've found.

[Brandon]

BTW West Marine will often price match Oreilies and other places if you play your cards right...

I bought a LOT of Delo100 40wt from them at OReilies prices (just sent them a screenshot of the web-page).

I run nothing but straight weight oils in the Detroit 2-stroke.

I get my info straight from Detroit:
http://brandon314.files.wordpress.com/2012/05/detroitdiesel_lube-oil-fuel-requirements.pdf

Skip to section 2.2

[1951Bus]

Thanks everyone - will definitely take your advice!!

[wg4t]

A funny, Greyhound used SAE30 in all 71 Series DD engines also used it in the front & tag hubs.
Me, I ran SAE50 in my hot rod 8V-92, never a spun rear main.
Dave