15W-40/5W-30 Amsoil

[slowneasy]

Have an oil change coming up and seems that I read that 15W-40 oil was good for this temperature range, anyone remember?

Also, is it okay to switch between these two listed oils for summer/winter use?

Finally, which is the better of these two gear lubes, 75W-90 or 75W-140 Series 2000? I don't do a lot of towing at the moment.
Thanks in advance for the help.

 

[Pete Peterson]

Boy, these are some loaded questions!! #ad
#ad
!!
Anyway the manual says to use a 15W40 so the Amsoil fits right in. But the proponents say that the 5W30 works better for fuel milage with the same protection, Hummmm?? With the 15W40 you be covered all the way around, its good oil. On the diff. oil either way you will be okay. Some of us use the heavier oil 75-140 synthetic cause we know it protects us no matter what, BUT then the 75-90 is better for the fuel milage thing again, Hummm ?? Anyway you work it you will be doing okay with the Amsoil just make sure you have allowed your motor to break in before you switch, oh say 15 to 20 thousand if you ain't towing... ... . Pete

 

[Cooker]

In the engine, IMO stick with the 15w40 year round. I don't think the temps in your neck of the woods come close to warranting the use of 5w30. Also IMO, the 40w on the top end protects internals a bit better.

If you tow or work the truck in any way, 75w140 for sure. Otherwise the 75w90 will be fine. IMO 75w140 is the way to go regardless of how we use the truck. A while back a member received an email from Dana/Spicer saying that the recommended oil was 75w140 unless the truck was in extremely cold climates.

As far as any difference in MPG's between the weights. I think it would be difficult to find a difference in MPG's from using the different weights mentioned. If you are comparing apples to apples, which we are doing in this case, ie Amsoil to Amsoil. If we were talking conventional oil, then perhaps differences in MPG's could be found.

JMHO, Ryan

 

[jsimpson]

I tried 5-30. It's so thin that I was blowing oil mist out the breather at an alarming rate. I'll not use it again in a diesel.

------------------
http://coffeewithJesus. homestead.com/web1.html 89 1-ton, Amsoil System 3000 5-30,K&N, cleaned-up exhaust with Dynomax straight-thru, rebuilt injector pump, thermostatically controlled twin 14" Permacool electric fans, intercooler, modified 518 OD transmission, Gear vendors OD controler, Reese Titan 2. 5" receiver, R-134 refrigernt, louvered front fenders, 93 aftermarket smoothie grille, new Dupont Chromacolor black, black-and-red rubber rubstrip, black headlights, powdercoated bumpers; 78 35'Avion, 93 Lance 900 slide in with generator and power jacks. To see my truck, Click on: <A HREF="http://albums.photopoint.com/j/AlbumIndex?u=1169022&a=10097213

Jesus" TARGET=_blank>http://albums.photopoint.com/j/AlbumIndex?u=1169022&a=10097213

Jesus</A> saves!

 

[C Schomer]

The 2k 75w90 has done very well in mine towing fast and hard. I switched after Dana told me it was the best stuff they ever tested - including 140's. That was 2 yrs ago and they hadn't tested any LE lubes. I'd like to see what they would have to say ! Craig

 

[C Schomer]

Jsimpson, do you think the electric fans cool as good on a hard pull as the stock setup? My temp goes about two needle widths past center now. Does the A/C override the t-stat? That sounds WAY better than a Horton - I'm not sold on slamming the fan on at high speed! Craig
Yes Jesus saves - that's why he never looses his files!! HA, I couldn't resist that one! That was an e-mail joke I got a while back.

------------------
97 3/4Ton, 2WD, 5SP, #11 Plate, AFC kit, 14 Housing, AF942M Air filter, Straight Thru Cat, 4"From Turbo, Airlift, Shortened Frame, Custom Bed, 24CKFS Sunnybrook, HEY FORDBOY POWERSTROKE THIS!

 

[Deezal Man]

Having used both, and noticing your from CA, I'd stick with the 15w-40. My only cost justification for the 5w-30 has been cold mornings. I have not seen enough of a MPG increase to offset its heafty cost. I may give the AMSOIL 15w-40 a shot next winter. .

Yes it would be ok to switch between the two in winter/summer. I'm a fan of leaving things drain over night. You'd be surprised how much remains in the Cummins for a few hours after pulling the plug. OMO.

 

[John]

Originally posted by Cooker:
I don't think the temps in your neck of the woods come close to warranting the use of 5w30. Also IMO, the 40w on the top end protects internals a bit better.

I used Amsoil 15W-40 HDD&M, switching to the Series 3000 5W-30 HDD at the last oil change interval. Oil analyses have shown that the Series 3000 5W-30 is superior to the 15W-40 HDD&M in not only my oil analysis reports but everyone else on this BB that has tried both (and posted results), regardless of ambient temperatures or load etc. The 15W-40 HDD&M is an excellent synthetic, the Series 3000 5W-30 is in a class by itself. #ad


I'm running Amsoil Series 2000 75W-90 in both of my differentials however, if I was heavily loaded most of the time I would probably go back to using the 75W-140 in the rear differential.

 

[John]

Originally posted by jsimpson:
I tried 5-30. It's so thin that I was blowing oil mist out the breather at an alarming rate.

I use NO oil between oil change intervals using Amsoil Series 3000 5W-30 HDD synthetic. I would think if you are "blowing oil mist out the breather at an alarming rate" you had better find out what the root cause is.



[This message has been edited by John (edited 03-26-2001). ]