Kinda sorta.
85 and 90 SAE viscosity are both ranges as are 30 and 50 SAE motor oils. Compare actual typical Vis at a couple temps (40°C and 100°C) for example.
Amsoil Severe Gear or HPL?
- Thread starter Johnny248
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85 and 90 SAE viscosity are both ranges as are 30 and 50 SAE motor oils. Compare actual typical Vis at a couple temps (40°C and 100°C) for example.
He did state its a safe bet to use anything that has SAE 2360 approval though and Valvoline 75W90 is on the list.
Thank you Subie and everyone that participated in the testing. Great info!
One question on the PDSC testing and Amsoil / Motul numbers. As I understand, the reporting units are time of which the oil was placed under oxygen pressure and heat. But the amount of heat may be different if the initial oxidation occurs within 10 minutes. so its re-run at a lower tier. Essentially it looks like the Amsoil and Motul are much worse in this test than the others. but is that because the others are run at lower temps? Sorry if this was already asked in the Mega thread.
One question on the PDSC testing and Amsoil / Motul numbers. As I understand, the reporting units are time of which the oil was placed under oxygen pressure and heat. But the amount of heat may be different if the initial oxidation occurs within 10 minutes. so its re-run at a lower tier. Essentially it looks like the Amsoil and Motul are much worse in this test than the others. but is that because the others are run at lower temps? Sorry if this was already asked in the Mega thread.
CleanSump
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Local Amsoil rep may have what you want on the shelf near home. Just call and go pick it up.
You can find them on the Amsoil website or google maps. I've been using Severe Gear since the '90s I think.
You can find them on the Amsoil website or google maps. I've been using Severe Gear since the '90s I think.
Or use the BITOG Amsoil guy.
I do sell locally at my cost, most dealers have some mark up. Yes there are free shipping and other offers if timed right.
I guess I should have been more emphatic, more clear when I said I changed multiple things at the same time. The aforementioned differential fluids, the engine oil, the transmission fluid, and the air filter were all changed at or near the same time. The vehicle was purchased used, with Carfax reports that did not report abuse or misfortune, but didn’t completely point to perfect pre-conditions. Supposedly the engine oil was previously 5w30 (Chevy) dealer bulk; the transmission and differentials fluids were basically unknown. It is speculation, but what if the dealer engine oil was “mistakenly” 0w-20, the previous differential fluids were 75w-85, the transmission fluid some LV fluid (2x drain & fills with the Subaru HP…which is thicker than LV/Dexron IV) and the previous air filter better than than the Fram AF Titanium one I installed. FWIW, I’m getting below expected fuel economy, whereas after initially buying it, it got expected, perhaps even better than expected. So could just be something has deteriorated or anecdotal results misleading. Oh, and battery changed out, so maybe some “learning” got reset, and my lead foot (not really) affecting ECM / TCM learning. By the way, I just had plugs changed (old ones didn’t look that bad), and checked the PCV, which seemed OK, but will get replaced FTHOI.
I chose the Amsoil for this vehicle on purpose, over the Motul and over the HPL. So, let’s interpret this as my consternation that fuel economy went down, for whatever reason, despite my best efforts.
If I were to do it again, maybe I would have changed one thing at a time, then seen what change correlated (as opposed to “caused) to what effect. But I would have still lead with the Amsoil for the diff’s…totally based on SubyRubi’s commissioned tests and even overall reputation. Re the transmission, I don’t have enough info to justify not using Subaru’s official ATF (HP) for the 5EAT, though @Pablo or @HPL Plant Manager might chime in.
FWIW, for the Ford Transit rear differential, Pablo was recommending Amsoil’s 75w-110 instead of their 75w-90. Given that Ford was yelling in my other ear to stay with 75w-85, I chose the ”middle ground” of the HPL 75w-90…per Subie’s tests, it’s viscosities were in between the SVG 75w-110 and their 75w-90, let alone Motorcraft (or anyone’s) 75w-85.
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Here were results of 1st & 2nd tests commissioned by @SubieRubyRoo just so you have it handy. It appears to me the Amsoil and HPL (and Redline, except maybe for super cold performance) offerings rose to the top, at least in certain respects such as shear. IMHO Motul wasn’t bad at all, providing credible protection at lower viscosities than most (possibly making it a viable alternative to 75w-85) with exceptional resistance to KRL shear, and a few others weren’t far behind either. No, Valvoline and Mobil 1 did not suck, but neither did they rise to the very very top. Since one of my uses was in a Subaru, I noticed the Subaru gear oil didn’t totally suck either, though its KRL was mid-pack at best. I wish @HPL Plant Manager would weigh in on the 4-ball wear vis-a-vis CC vs non-CC results, since their “CC” version was one of the worst (and non-CC one of the best). As a reminder, they told me they only have once version now.
From this point forward, Just my opinion: the KRL shear test is important, as well as the wear & weld tests. Viscosity and to lesser extent Brookfield (given I live in Texas…in Alaska or N. Dakota it would be of much greater importance) also affected my decision. PDSC could also be important, but as noted, there are disclaimers relating to using it as a qualifier. ***These are just my hack interpretations.***
From this point forward, Just my opinion: the KRL shear test is important, as well as the wear & weld tests. Viscosity and to lesser extent Brookfield (given I live in Texas…in Alaska or N. Dakota it would be of much greater importance) also affected my decision. PDSC could also be important, but as noted, there are disclaimers relating to using it as a qualifier. ***These are just my hack interpretations.***
Wait a minute, you're not calculating the fuel economy manually/by hand?
Just making sure you're not going off the computer. That's all. They aren't as accurate.
Well aware. My Ford Transit computer is abysmal, sometimes reading as much as 2 mpg high. The Subaru 3.6’s was better initially, but seems to have gotten more and more “optimistic” of late, but not as bad as the Ford. My older 07 Subaru OBXT stick shift turbo has been pretty accurate, usually within 0.5 mpg.
Valvoline is pretty much available anywhere. This would lead me to believe that a good amount of differentials are filled with it by anyone who actually takes the time to change out the fluid. And when you take account how many trucks are roaming around the US that have NEVER had their differential fluids changed, it makes you wonder how much all of this even matters? Working in the service business, I see far more axle seal, or pinion seal leaks than I ever see differential failure. Not saying they don't fail, but it's a very over looked fluid that one could argue could actually be "lifetime" fluid.
About a week or so ago we replaced pinion bearings in a newer Ram 1500 that were screaming and the rollers had huge chunks of delamination or rot. Truck had 101k and the carfax showed that all of the drive line fluids were replaced at ~60k. Korean bearings fwiw.
I'm part of the old school who changes diff's and T-case every 30k on my vehicles. I tend to hold on to vehicles for at least ten years, or whenever the body starts to rust away. To me replacing the fluids is cheap insurance, gives me a good feeling, and something to do when I'm bored lol
I saw a reel on Instagram recently showing someone draining old and gross diff oil and talking about the importance of changing it on time, and the comments were full of people saying they had 200-300k miles on Toyotas and had never once changed it. Shocking to me, but it's interesting to see how the non-BITOG crowd manages their vehicles. Not my approach, but interesting.
Worked for a water company after leaving college & before entering my "career". My service truck was an early to mid 90's GMC (this is around '03 or so). One day the rear end started howling. Told the shop maintenance foreman when I got back mid day. While I had lunch at my desk, through the window I watched one of the auto techs quite literally pump grease into the differential pumpkin. Made sure to ask them if they but gear oil in, hoping I mistook a syringe tool to inject gear oil, and the guy said "nah, filled it with grease. She'll be good for a while". Couldn't believe what those guys did in that shop.
How do you get all THAT gunk out? Maybe that’s why HPL sells a differential Cleaner product (separate from their normal Differential Life products).
No idea. I left a few months later to start my power ops career. Stuff like that would get you walked straight out the door in the power system world
How can you tell how your diff is doing? I can't hear mine I don't think.
At negative temps I can tell that the transfer feels darn near froze. My last few runs have been amsoil and motul and things moved much easier when cold.
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