BirdShot

Also likely from break-in, dirt contamination can be pretty high in new components.

Wear metals look low, VIS is in range, looks pretty good.

TAN is a little higher than I would expect, did you also get FTIR results to compare?

INDYMAC

As promised INDYMAC.

I just got the results and they were as I expected. This again was the first fill after the break-in and the Iron levels indicate some break-in still occurring. There was also a little more oxidation than what you'd want to see at this many miles - again probably due to elevated friction from the break-in. I have no idea where all the silicon comes from. It wasn't particularly dusty the day I installed or drained the fluid.

This will be a little painful as my scanner does not work so I'll have to manually post them:

Wear metals:
Iron: 162
Chromium: 0
Nickel: 7
Aluminum: 0
Copper: 0
Lead: 0
Tin: 0
Cadmium: 2
Silver: 0
Vanadium: 0

Contaminant Metals:
Silicon: 48
Sodium: 2
Potassium: 0

Multi-source Metals:
Titanium: 0
Molybdenum: 2
Antimony: 0
Manganese: 3
Lithium: 1
Boron: 101

Additive Metals:
Magnesium: 3
Calcium: 8
Barium: 0
Phosphorous: 1108
Zinc: 30

Viscosity cSt @ 100C: 24.4
Acid Number (mg KOH/g): 5.92
Water: <0.1 FTIR
[/quote]

Thanks for posting this Slipstream. I really do prefer this type of information to go along with marketing information. As Ronald Reagan once said, "trust but verify"!

What gear oil was this, how many miles in service, and how many miles on unit? Which lab? How did the oil look when drained? Anything on the drain plug?

Silicone is a common anti-foam agent in gear oils. That's what I think the test picked up on, unless there were some Si products used on the rebuild. What was the problem with your original diff and what gear oil were you using?


It's difficult to evaluate TAN and kV unless you know the fresh oil starting point. Have you ever seen a fresh oil sample tested?

BirdShot

It's true that it's best to compare using a new lube sample reference, but you can figure a GENERAL starting point of TAN by looking at the additive levels. This is of course not true with all fluid's/fluid types, but generally.

Same with the viscosity, Slip says he used an SAE 140 and it does fall in the lower side of that range, although it is a big range.

I would argue that Si at this level is not in the form of anti-foam (15 ppm would be at the high end for a new sample) but is in fact in the form of dirt.

Just my experience.

zeroptzero

This is an upgraded diff, does it come with better internals compared to the stock unit in terms of metal quality, hardness, etc.... ? I thought the sample looked quite a bit better than my run with Amsoil 75w140 but the two diffs could be quite different in terms of internals.

slipstream444

The sample was tested at Oil Analyzers. I misspoke and stated there was just at 12k miles on the sample, that's the total mileage on the unit. There's a little over 9,500 miles on this fluid. There was a smudge from the mag plug - but not excessive. The oil was slightly darker than the fresh stuff - but not excessively so. The fill was Amsoil SG 75W140 (I originally thought I had 75W110 in there... but the proof was in the viscosity result). The app I use for tracking maintenance doesn't display data in the most user friendly manner and it doesn't export to programs like Excel unfortunately. All my previous records were done by hand.
The original/break-in fill was Amsoil SG SAE250 (8oz) topped off with SG75W140. You'd have to ask PuddyDad why he chose this mixture for the break-in fill. The current fill is in fact SG 75W110.

I haven't had a virgin sample tested to date. However, the lab did comment that the oxidation level was slightly higher than usual for this fluid and the zinc levels were also a bit high for SG75W140 - this indicates they likely have a virgin sample database - I'll have to contact them to see if this is the case or not. This is also why I was a little concerned about the silicon contamination. I'm going to contact PuddyDad to see if this may be residual from the polishing involved in the build he did. The high zinc levels are possibly due to residual SAE 250 - I'm not sure of that yet.


The diff is a PuddyMod Racing Stage 4 diff, which is cryo-d, polished and matched to perfection. It's also reinforced. I'm running a MazdaSpeed 4.44 gearset.
As mentioned in a previous post, the previous diff was a poorly set-up, early 4.57 gearset. It never failed - but it sure was noisy!

zeroptzero

Looks like a good UOA to me for that mileage. My silicon reading was 6ppm's on the same fluid. Are there any sealants used in the assembly of the diff casing , that can sometimes skew the silicon results. It would be interesting to see how the 75w110 compares on a future UOA.

S2oooNvegas

Cliff notes for this thread.

Just run LE607/1605 and youll never have to worry.

I just did another board members diff fluid change yesterday. It is karim on our vegas boards so you can PM him if youd like.
He tracks his car probably more than 90% of the people on ths board. He lives for road course/track days. Its been so long i forgot that i put LE607 in his diff. But he reminded me when he dropped it off with a new qt and asked me to do the service.
I texted him the moment i pulled the drain plug. I couldnt believe it... not even ONE shaving or metal particle. in god knows how many super nasty track days in a car with stickys on all 4 being competed with as hard as possible at the track.
That is all i need to know to say that i have now been putting LE607 in diffs since 2004 and will never change that.
It works perfectly and zero failure rate in cars that run as hard as can possibly be run. Several of my builds make near 500 whp on stock diff and no failures and...... we live in las vegas. Its been freezing (30 degrees) on several mornings lately and it gets to 110 in summer.
Hope this helps those who may be looking for results.

INDYMAC

Where do you keep finding LE 607? It's been discontinued for several years now. LE 1605 is the replacement.

sillyboybmxer

just did my diff fluid today,..had 20k miles on the LE that was in there, lots of auto x's, no metal, no smells.....first time i have refilled it with something else, amsoil, 75w 110, only because i found it locally.

starchland

curious to see how the drain plug looks at the end of this season running amsoil 75/90, since the last 3 years I was running motul 300 so I have a pretty good trend of what the pug looked like.