Diff oil to quiet diff whining

[SubieRubyRoo]

No, that is a process called "Micronite"

Are you referring to iso finishing, also known as rem finish? I’ve heard from a very reliable source this has actually led to very disastrous results because the highly polished finish doesn’t have the ability to “hold” any gear oil at the interface between the gears, and cannot prevent metal to metal contact. Therefore the gears experience higher wear rates and eventually fail under load. Bad juju. If anything get them coated with a dry film lubricant.

 

[21_6.7f450]

If the pot had fins and a bit of air moving across them, it's peak temperature would drop because it is able to shed heat more efficiently given the same heat source.

 

[4WD]

If the pot had fins and a bit of air moving across them, it's peak temperature would drop because it is able to shed heat more efficiently given the same heat source.

Nothing to do with capacity
And Banks aside - no OEM does flat backs …
(Some do finned aluminum with gear contour)

 

[21_6.7f450]

Absolutely. It's the ability to shed heat and magnets where there were none that I'm after. My F450 had a stock finned aluminum contoured cover but silly Ford "forgot" to put magnets in the differentials. With 150k mile oil change intervals, and dealers leaving them quite low at the time of delivery, no magnets is not good. Most guys never check much less change the gear oil. OEMs know what's best, that is overridden by the desire to save a buck.
$3800 to rebuild a Dana M300 is cheap. I have a friend that has a 2018 F350 DRW that pulls a bi-deck six car. Every 14-16 months (100k) he gets it rebuilt with a new R&P and bearings. It's got 461k miles. He is content with that. He does grumble about getting a new DPF every 150k for $4,500 because nobody bakes them locally.

 

[4WD]

The principle is still solid
The contour makes the ring gear an impeller that pumps maximum flow to the ring & pinion interface

 

[21_6.7f450]

It likely isn't enough to keep them alive when they are working hard. I'll continue to live dangerously and take my chances with my MH covers with magnets that the factory did not provide and my Redline 75w140.
Diff failure is not ever on my mind. Ways to prevent CP4 failure is.

 

[dnewton3]

67 + 23 = 90.

90 + 10 = 100

Yup.
I clearly had a senior moment.
I stand corrected; consider me admonished!


I really find it hard to believe, despite my bad math, that this magic ratio of three different viscosities somehow made a lube that quieted the diff by "40%".
Perhaps send a VOA to a lab and find the resultant real viscosity? It's probably similar to any OTS product anyway. something like a 75w-110?
And why 10% FM? That's way more than what most diffs call for (typically between 4-8 oz).

 

[thastinger]

Are you referring to iso finishing, also known as rem finish? I’ve heard from a very reliable source this has actually led to very disastrous results because the highly polished finish doesn’t have the ability to “hold” any gear oil at the interface between the gears, and cannot prevent metal to metal contact. Therefore the gears experience higher wear rates and eventually fail under load. Bad juju. If anything get them coated with a dry film lubricant.

Yup, REM is a similar process, just highly polished gear surfaces. I have no first hand knowledge of the process doing anything but improvements.

 

[Jetronic]

Yup.
I clearly had a senior moment.
I stand corrected; consider me admonished!


I really find it hard to believe, despite my bad math, that this magic ratio of three different viscosities somehow made a lube that quieted the diff by "40%".
Perhaps send a VOA to a lab and find the resultant real viscosity? It's probably similar to any OTS product anyway. something like a 75w-110?
And why 10% FM? That's way more than what most diffs call for (typically between 4-8 oz).

I think the friction modifier quieted the diff

 

[TiGeo]

Liquimoly MoS2 for gears.

 

[SubieRubyRoo]

Liquimoly MoS2 for gears.

Because it quiets whine or because it helps reduce sliding friction by plating surfaces under intense pressure?

 

[TiGeo]

Because it quiets whine or because it helps reduce sliding friction by plating surfaces under intense pressure?

I don't know but dangit...it's LM and I use it so why not.

 

[SubieRubyRoo]

I don't know but dangit...it's LM and I use it so why not.

Well if MoS2 is good, MoS3 must be mo’ betta, right? (is that what trimer moly is? )

That being said, MoS2 in differentials is one of the applications that it actually shows a true benefit. LM or not it’s beneficial.

 

[TiGeo]

 

[dfarr67]

If you put that much effort into the diff- I don't think an oil will do much. Time to swap out the diff maybe the tubes are bent or sagged.

 

[Jetronic]

Liquimoly MoS2 for gears.

I was thinking along the same lines: if friction modifier for use in limited slip differentials reduces the wine, something like red line shockproof, graphite, WS2 or MOS2 has a decent chance of helping

 

[TiGeo]

I was thinking along the same lines: if friction modifier for use in limited slip differentials reduces the wine, something like red line shockproof, graphite, WS2 or MOS2 has a decent chance of helping

I will say, I *think* I have a bit of r. diff whine but it could be the DSG trans which at over 100K, is known to get a little of that. I used the MoS2 for gears in my r. diff and f. bevel box when I changed it about 6 mos ago, no idea what if anything it did for it. I also probably over-dosed them both, one tube per and I could have probably split it between them with barely a qt of oil each.

 

[ecstaticaaa]

Well if MoS2 is good, MoS3 must be mo’ betta, right? (is that what trimer moly is? )

That being said, MoS2 in differentials is one of the applications that it actually shows a true benefit. LM or not it’s beneficial.

Could you confirm I can dunk this stuff into my rear differential on 2010 rx350? I don't want to mess anything up, this presumably shouldn't hurt the AWD? Just got quoted a rather astronomical amount to replace a "viscous coupler" after it developed a whine. Not much info out there on replacing specific bearings if I want to try it myself.