Any thoughts on ACD & HDD

Status
Not open for further replies.
Joined
Aug 28, 2014
Messages
708
Location
TX & ON
Hi, new here.

Pros/cons of HDD or ACD on the first 2 vehicles in my signature vs AMO ?

They will be operated in -40 to 110 or so, mixed city/highway, everyday.

User experiences and balanced views please, not interested in stirring up an oil war on my first post.

Regards.
 
Amo is 10w-40, hdd is 5w-30 and acd is 30w/10w-30.

I'm not seeing a compelling reason to select a 10w-40.

HDD will have some obvious advantages in the cold over ACD, so I'd probably go that route. I have and use ACD for other stuff,and would consider it, if it weren't for the -40 temperature part.
 
AMO gives me about 20psi hot idle and I've used it in -40, though it was definitely happier at -20.
T6 would not give me more than 12psi at hot idle.
Both flow well enough to the valvetrain, but there's no compelling price difference between the two in Canada.
The above values on the first vehicle - no fuel dilution issues btw.
I hear ACD and HDD are thick 30w oils - any thoughts on which would give me higher oil pressure at hot idle ?

Originally Posted By: JHZR2
Amo is 10w-40, hdd is 5w-30 and acd is 30w/10w-30.

I'm not seeing a compelling reason to select a 10w-40.

HDD will have some obvious advantages in the cold over ACD, so I'd probably go that route. I have and use ACD for other stuff,and would consider it, if it weren't for the -40 temperature part.
 
Originally Posted By: dnewton3
What are your OCI goals?
Anything other than temp extremes to ponder?
Price threshold?


Not a particular concern, as I have a couple gallons of HDD & ACD handy.
 
I reckoned you'd provide some input based on your propensity for 10w-30 oil dnewton; don't be churlish.
Thought the resident Amsoil dealer would chime in as well.
Alright, let's narrow it down to AMO vs HDD for the '81 pushrod v8 in -40 to +100; mixed daily driving, average bearing clearances and the odd 2000lb critter in the bed while in four low.
Quote:
You already own them; use what you want.
 
HDD will outperform in the extreme cold, and also has a higher viscosity at operating temperature.

How often will your vehicles see the frigid temperatures? At -40 you would see the benfits of synthetic fluids in every compartment (power steering, transmission, differential), as well as block/pan heaters.
 
You meant HDD would have higher operating vis than ACD (not AMO) correct?
The two first gen Dodge trucks see the cold; all synthetic in the tranny, transfer case, diffs, steering and grease.
-40 may happen a couple times a week within a 2 month period, but it's -20 or so most of the winter.
Would it still be worth going to HDD from AMO given hot summers as well, and yearly oil changes?
 
If it's getting down to -40 a couple of times a week for a two-month period, you should be running a 0W-something to ensure good cold flow in that extreme condition. Then change to something thicker when the warm weather comes.
 
Seems like the HDD would be the best choice year round in both cold and hot extremes. The HDD could handle both. The ACD is certainly a stout oil, but -40 is just too cold for it. Heck I think Amsoil lists the ACD cold flow at -37. If you have both, give them a try and see what you think is best.
 
Will do powerstroke.
The AMO in my sump is rated pretty decent for cold flow as well, but will see how the HDD does.
Hopefully the HDD has decent operating temp viscosity for year round usage.
Any thoughts on ZRT ?

Originally Posted By: Powerstroke
Seems like the HDD would be the best choice year round in both cold and hot extremes. The HDD could handle both. The ACD is certainly a stout oil, but -40 is just too cold for it. Heck I think Amsoil lists the ACD cold flow at -37. If you have both, give them a try and see what you think is best.
 
Status
Not open for further replies.
Back
Top