Is Everyone Happy with Redline Differential Fluid

[Bror Jace]

Yes, Idrink, it might be a bit of overkill ... but as you point out the cost is low and the cost of a replacement unit would be several hundred ... maybe a thousand or more.

Diffys are often ignored by most owners ... and I bet the average unit doesn't see fresh oil until well after 50,000 mile mark, with many units approaching or exceeding 100,000 miles before their first (and only?) service.

 

[INDYMAC]

I have only seen one UOA of RL 75W90 GL5 gear oil and it was nothing to write home about. In fact, it was unacceptable. Does anyone have any good UOA's of any RL gear oils. I personally won't try it until I see a good application for it.

 

[Pablo]

The only differential I ever had fail was filled with Redline 75W-140. The whole differential (Dana 30, 3.91) sort of ate itself, so after the noise started. I can't say if the fault was the fluid, but I sure was angry to have this happen within a year of fluid change. Obviously this was before I was an Amsoil dealer, but just before. The exact replacement was filled with the now obsolete Amsoil S2K 75W-140 and driven many years hard, including towing, with no issues. I still have the UOA on that Redline fluid. Wow. Fe was like 600 ppm or something.

Indymac makes a great point. People just say stuff about these fluids with no data other than maybe it "shifts smooth".

 

[Steve S]

Pablo ,the only engine failure I ever had was running Amsoil 10w/30 .I know that it was not Amsoils fault. I took the engine apart and found G.M forgot a cam bushing to keep the roller cam from wearing the cam cover out. Redline oil is the gear oil of choice. Don't want to use Redline? use Delo ESI gear lube.

 

[Pablo]

That's exactly why I haven't posted that in the past. Steve S launches into the usual mode - and I mistakenly thought the discussion was about gear oil. The point is that Redline is the gear oil of choice in people who just go by emotion and no facts. If you don't want to use Redline use Amsoil Severe Gear.

 

[Idrinkmotoroil]

Pablo, what do you think about Bob's gear oil test, on Amsoil's 80w-90 compared with Schaefers fluid ?. Quite often we don't get enough information on gear oils, then when you do it can almost be confusing (like Bob's test). Never quite sure what to believe and you hate to be guinea pig. I've got Amsoil's severe gear fluid in my transfer case -75w-140, and Redline's 75w-90 in the diff right now.

 

[Pablo]

Bob's tests are very non-real world and not standardized and not scientific. Plus they are very old.

 

[JHZR2]

Quote:

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Indymac makes a great point. People just say stuff about these fluids with no data other than maybe it "shifts smooth".

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Well it is a very well known fact in the E30 BMW world that redline helps to quiet whiny diffs. Whether this is due to a superior film, additives or whatnot, I dont know. I just know that it quieted the diff compared to M1 and even the XJ synthetic (european) castrol fluid, which is what BMW uses in all its diffs these days, even the very HP cars.

Ive heard great things about amsoil, but have never used it. RP works well in our toyota previa diff, M1 has been used in my MB and my chevy truck, and Id venture to guess even dino based diff oils would do quite well for everyday car usage.

I have high doubts that any diff fluid would be the cause a diff failure, short of some other issue.

If a diff fails before 300k, there is an issue. My BMW diff got whiny at 100k or so, but my car was a flood car, and the diff was not replaced, per the records... so it stands to reason.

JMH

 

[KBFXDLI]

Amsoil vs Redline? You guys are splitting hairs here..both are excellent product...if that is your field of choice I would go for price and availability. Summit Racing is 1/2 hour from home for me so I can get all the redline I want. But several of my friends have used amsoil severe gear in everything from race cars to tow trucks and never a failure in really stupid severe service. So take your pick..both are winners. But I know a guy who ran a tow truck 200k on a single amsoil change.

 

[INDYMAC]

All of these anectdotal testimonials are very compelling and captivating, but here's something that may actually shed a different light:
http://theoildrop.server101.com/forums/s...ge=0#Post792492

 

[tdi-rick]

one UOA test vs another is pretty meaningless. Trends need to be established, etc. etc.

 

[INDYMAC]

Well, I'd have to agree. So far RL gear oil looks well below average. Show me what you got!