Mobile Delvac/Synchromesh VS. Amsoil MTG 75/90 for G56

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Originally Posted by 2009ram2500

1) I ran a 5 quarts (5/8 or 62.5%) Mobile 1 Synthetic Transmission Fluid 50 SAE (the one in the picture) which has a manf tested viscosity of 132CsT at 40c / 17.5CsT at 100c BLENDED with 3 quarts (3/8 or 37.5%) Amsoil Manual Synchromesh Transmission Fluid (the one in the picture) which has a manf tested viscosity of 87.6CsT at 40c/ 13.9CsT at 40. This blends weighted average viscosity is 88.76CsT at 40c / 14CsT at 100c. I ran this blend for 25,000 miles in my 2009 G56. This blend would max out at 180F to 190F in about 200 miles at 100F ambient temps.
Here's my pan results after 25K on this blend
https://www.cumminsforum.com/forum/...elvac-50-amsoil-synchromesh-results.html

2) at 50K I switched out the trans fluid to the Amsoil Manual Transmission and Transaxle Gear Lube 75W-90 (MTG 75W-90) (the one in the picture and the one I referenced in my "other" thread on here which has a manf tested viscosity of 87.6CsT at 40c/ 13.9CsT at 40c. I've ran this for 5,000 to -8,000 miles and running this MTG I tracked the results making the same trip under the same load conditions and similar ambient temps

Here are my temp/ miles results with the MTG 75/90:
30 miles to get to 140*
100 miles to get to 160*
140 miles to get to 180*
180 miles to get to 200*
200 miles to get to 220* ambient started at 63F and got to a max of 92F around mile 200

3) Additionally I ran the MTG on a different trip pulling a different trailer and got these results (which differ from the results above):
Now on my last winter trip with the MTG 75/90 it was 63F outside and I did 240 miles and trans never got above 200F. On the way back ambient temps where 82F and temp remained 180F until I pulled the white water grade outside Palm springs CA headed west (about 3 miles) at about 65-70mph with the 7k box trailer. As soon as I started the grade temps started climbing and didn't stop until about 220F which is where they level off and seem to peak out with the MTG 75/90 On a side note; if I shut off the truck, the trans cools down from 220F to 160F in about 12 minutes.

Conclusions:
1) Both the MTG and the 3/5 blend have the same viscosity so the differences in temperature and shifting characteristics can only be from differences in additive packages not viscosity.

2) The MTG acts different in different ambient temperatures and shear loads. EG: It stays cool (180F) under 80F ambient but heats up very fast when over 90F ambient and under high shear loads.

3) The Blackstone anayslsis of both the Delvac 50 SAE & the Amsoil Synchromesh 5W-30 are posted in this thread but I do not know how to calculate the actual additive content based on the weighted averages of my blend to get at least a close ballpark of what was in the 3/5 (37.5%/62.5%) blend I ran and tested for 25K miles.



Given these results, here are my questions

1) why does the MTG get hot so much faster than the Delvac mix despite having the same viscosity?

2) what causing the MTG fluid temps to rise under load VS. running flat and why does a 20 degree increase in ambient temps raise the MTG fluid temp so much?

3) Why can I not get it in to gear above 210/220F with the MTG 75/90 even though it's thinner when hotter ( aka it's not the viscosity)?

4) Is it better to run the manual trans at 180/190F with the Delvac/Synchromesh mix OR 220F with the MTG as there are no clutches ( like in an auto trans), since it's all gears and brass synchros?



Thanks for the clarification. One more question: Were you measuring the actual fluid temperature or the transmission's case temperature?
 
I have an expanded custom side cover that I have a temp prob in so from the side of the case.

If you click on the link in the post you quoted above called " Delvac 50 + Amsoil Synchromesh Results" it shows the cover and the temp probe and what the oil looked like upon removal after 25K on the 3/5 blend.

Also after 25K is this considered a lot of brass or not?
 
Ok so I called Blackstone and they said their VOC tests are conducted on 1 ML of samples

Based on this here how the 3/5 blend stacks up against the Amsoil MTG 75W-90 using a weighted average based on the virgin tests provided in this thread.

3qts (37.5%) Amsoil Synchromesh/ 5qts (67.5%) Mobile Delvac Trans Fluid SAE 50
Aluminum: 0.75
Iron: 2.25
Boron: 168.4
Silicon: 4.0
Calcium: 42.62
Magnesium: 1761
Phosphorus: 1236
Zinc: 349.625
*This one takes much longer to get hot and maxes out at 180F to 190F


Amsoil Manual Transmission & Transaxle Lube 75W-90
Calcium: 262
Magnesium: 1
Phosphorus: 544
Zinc: 3
*This one gets hot much faster especially under heavy load is more affected by ambient temperature and maxes out at 220F



Based on the VOC content listed above can someone explain how these compounds correlate to my heat findings and how each of these compounds affect the performance and longevity of the transmission components, mainly the gears and hardened brass synchros?


Also what are good compounds to have and not have for brass synchros?


Thanks
 
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Originally Posted by 2009ram2500
I have an expanded custom side cover that I have a temp prob in so from the side of the case.

If you click on the link in the post you quoted above called " Delvac 50 + Amsoil Synchromesh Results" it shows the cover and the temp probe and what the oil looked like upon removal after 25K on the 3/5 blend.

Also after 25K is this considered a lot of brass or not?



OK, looked at the link and here are some thoughts on your results:

1) In my experience that is not a lot of brass particles so I would not be too concerned since you have a lot of engine with a lot of torque,

2) I think the better shifting results you experienced using the MTG only is because the MTG has specific friction modifiers for synchronized transmissions whereas the Delvac does not, and the Delvac/MTG mix dilutes that specific friction modifier, so that's the additive factor,

(NOTE: When are talking here about specific friction modifiers for synchronized transmissions that is a different friction modifier than is included for fuel mileage gains).

3) Hypothesis in terms of thermodynamics - The reason for the Amsoil MTG's higher temps is because the MTG is conducting heat from the gearing and bearings more efficiently than is the Delvac or Delvac mix, so the fluid temp and resulting case temps would be higher, which is good.

4) Reason for 3): the MTG has a higher amount of PAO and esters which have higher specific heat values than do majority Group III oils.
 
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Originally Posted by 2009ram2500
Ok so I called Blackstone and they said their VOC tests are conducted on 1 ML of samples

Based on this here how the 3/5 blend stacks up against the Amsoil MTG 75W-90 using a weighted average based on the virgin tests provided in this thread.

3qts (37.5%) Amsoil Synchromesh/ 5qts (67.5%) Mobile Delvac Trans Fluid SAE 50
Aluminum: 0.75
Iron: 2.25
Boron: 168.4
Silicon: 4.0
Calcium: 42.62
Magnesium: 1761
Phosphorus: 1236
Zinc: 349.625
*This one takes much longer to get hot and maxes out at 180F to 190F


Amsoil Manual Transmission & Transaxle Lube 75W-90
Calcium: 262
Magnesium: 1
Phosphorus: 544
Zinc: 3
*This one gets hot much faster especially under heavy load is more affected by ambient temperature and maxes out at 220F



Based on the VOC content listed above can someone explain how these compounds correlate to my heat findings and how each of these compounds affect the performance and longevity of the transmission components, mainly the gears and hardened brass synchros?


Also what are good compounds to have and not have for brass synchros?


Thanks



Okay, maybe I missed something and need further clarification. The Amsoil synchromesh is the MTF with a viscosity of about 9.5 cSt@100C or so, whereas the higher viscosity MTG is about 14cSt@100C.

So was the "mix" the Delvac + MTF or the Delvac + MTG?

I don't think the second analysis is correct since the MTG and the MTF share the same additive package as per my last analysis, they differ only in the mix of base oil viscosities.
 
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YES I think there is a LOT of confusion here:
It seems you have your fluids confused as to which fluid acted which way.


Refer to the 8th post with the pictures #4924832:
Pictures of fluids used

I first ran a 3/5 blend of for 25K miles:
62.5% Mobile 1 Delvac Synthetic Transmission SAE 50 (132CsT at 40c / 17.5CsT at 100c)
37.5% Amsoil Manual Synchromesh Transmission Fluid 5W-30 (87.6CsT at 40c/ 13.9CsT at 100c)
-You are calling this "MTF" but I think that's where your confusion comes in, I've always called it synchromesh
For a Blended Viscosity of 88.76CsT at 40c / 14CsT at 100c[/u]

*This the fist oil I ran and I ran it for 25K miles. its the one that warmed up slow and max out about 180F to 190F even at 100F ambient temps.


Second I ran the Amsoil Manual Transmission & Transaxle Lube 75W-90 This is known as "MTG" or "MTG 75/90" (87.6CsT at 40c/ 13.9CsT at 100c)

*This is the oil that heats up fast, gets hot under load and maxes out at 220F and is effected by ambient temps.


Let me know if I need to put the pictures in this post to clarify it even further.

Thanks
 
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Yep, it helps to get on the same page.
smile.gif


i was using the manf. designations since Amsoil MTF (9.9 cSt) is called, "Manual Synchromesh Transmission Fluid 5W30" and the MTG (13.9 cSt) is "Manual Transmission & Transaxle Gear Lube 75W-90."

Most MT fluids that are colloquially called "synchromesh" have a viscosity around 10.0cSt +, -, 2 cSt, because the first dedicated "GM SYNCHROMESH(R)" MT fluids came out around the 10.cSt viscosities.

See my answers above on your questions in post #4926255.
 
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Originally Posted by OVERKILL

I was thinking more along the lines of unpredictability in the impact on FM, AW...etc. Viscosity is relatively easily calculated (which he's already done). My comments were really meant to be more elementary: The Delvac product is tested and recommended by Mercedes. If his main concern with this product, and the reason he originally diluted it is the viscosity, running the 40 version from the same lineup makes more sense than blending two products from two different manufacturers in my mind where there are a number of unknowns.

Agree, you have a basis on unknown additive interaction or efficacy concern.
The issue OP is facing is huge delta in heat generation as a result of differential 'Coefficients of Friction' of sliding pairs of gears and bearing rollers between the two oil systems , whereas the delta in heat generation attributing to drag friction (as viscosity-related) is miniscule if not near zero between them.
As to SAE 40 version, that's probably a subject matter for another day if OP so desires .
 
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Originally Posted by MolaKule
Originally Posted by zeng
Originally Posted by MolaKule
Originally Posted by 2009ram2500


And on the heat issue, since there seems to be no real data on the Amsoil MTG I'll just have to assume there is some chemical make up that makes it generate heat under load or when exposed to ambient heat.


None of the fluids are exothermic.

Anytime you put in say a thicker 75W90ish fluid in a machines speced for a lower viscosity fluid, horsepower is converted to heat because you have to move the more viscous fluid and churn the fluid with more input power.


That's totally invalid in explaining OP's 'problems' .


It is perfectly valid and a scientific response clarifying what is happening with reference to Chemical Thermodynamics.

No oil "generates" heat. To generate heat, a mixture has to be exothermic, which means "energy from within the system to its surroundings, usually in the form of heat." Take a carboxylic acid and an alcohol and mix them to form an ester with byproducts. Once mixed, the internal reaction generates heat.

An oil may rise in temperature due to mechanical energy being transferred to it, but it does NOT generate it's own heat.

Many times science trumps archaic thinking and old wives tales.


Completely missing the point ..... , again.
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Originally Posted by zeng


Originally Posted by Molakule
It is perfectly valid and a scientific response clarifying what is happening with reference to Chemical Thermodynamics.

Again, None of the fluids are exothermic.

No oil "generates" heat. To generate heat, a mixture has to be exothermic, which means "energy from within the system to its surroundings, usually in the form of heat." Take a carboxylic acid and an alcohol and mix them to form an ester with byproducts. Once mixed, the internal reaction generates heat.

An oil may rise in temperature due to mechanical energy being transferred to it, but it does NOT generate it's own heat.



Completely missing the point ..... , again.
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It's called, "Education" ZENG and I have yet to see you present a valid scientifically based response.
 
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Let's try this again framing the question differently.

Here is how the Mobile Delvac Synthetic Transmission Fluid SAE 50, The Blend of 37.5% Synchromesh & 62.5% Delvac 50 (3/5 Blend) stacks up against the Amsoil MTG 75W-90. (I used a weighted average based on the virgin tests provided in this thread to calculate the 3/5 blends compound make up)

Straight Mobile Delvac Trans Fluid SAE 50
Potassum: 1
Boron: 267
Silicon: 1
Sodium: 3
Calcium: 45
Phosphorus: 1177
Zinc: 1
*I Didn't do any mileage vs. temp testing when I ran this oil straight but it was hard to get in 2nd gear from a stop. I attribute this to viscosity without having temp/mileage results to test it against.


Blend 3qts (37.5%) Amsoil Synchromesh/ 5qts (67.5%) Mobile Delvac Trans Fluid SAE 50
Aluminum: 0.75

Iron: 2.25
Boron: 168.4
Silicon: 4.0
Calcium: 42.62
Magnesium: 1761
Phosphorus: 1236
Zinc: 349.625
*This one takes much longer to get hot and maxes out at 180F to 190F


Amsoil Manual Transmission & Transaxle Lube 75W-90
Calcium: 262
Magnesium: 1
Phosphorus: 544
Zinc: 3
*This one gets hot much faster especially under heavy load is more affected by ambient temperature and maxes out at 220F




Based on the composition of these three different oils listed above;

1) Why does the MTG 75W-90 get hot so much faster than the Delvac/synchromrsh mix despite having the same viscosity?

2) What causing the MTG 75W-90 fluid temps to rise under load VS. running flat and why does a 20 degree increase in ambient temps affect (raise) the MTG 75W-90 fluid temp so much?

3) Why can I not get it in to gear above 210/220F with the MTG 75W-90 even though it's thinner when hotter ( aka it's not the viscosity)?

4) Is it better to run the manual trans at 180/190F with the Delvac/Synchromesh mix OR the MTG 75W-90 at 220F as there are no clutches ( like in an auto trans), but all gears and hardened brass synchros?


5) Which of the three compound mixes is best for the G56 trans with the hardened brass synchros and why?
 
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Bueler.....Bueler.....Bueler.....

After all that nobody has any real fact based information to answer the above questions?
 
Think most here advised against mixing … personally I'd contact both Amsoil and Mobil and not mention mixing just to see what they recommend on a clean sheet … and even ask about the 40 version …

I have used Amsoil Synchromesh in a Synchromesh application and Delvac 1 in hypoid applications … but have not mixed products in drivelines …
 
Originally Posted by 2009ram2500
Bueler.....Bueler.....Bueler.....

After all that nobody has any real fact based information to answer the above questions?

Coefficients of Friction of Base Oils (Black) drops with presence of Boron Nitride (Red) or Boric Acid (Green) additives within.


0Cof hBN nitride vs BA acid vs Base oils ; Capture.PNG
 
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Ok so I've got some new information that could use some clarification on.


1) I've read that Sulfur eats copper alloys including brass, AKA sulfur eats brass synchros, id this correct?


2) I was told be a tech at Mobil that Delvac 1 Transmission Fluid 50 has a GL-4 sulfur based EP additive package in it BUT I if you read Mobil's website it specifically states that this fluid is GL-4 NON EP with no sulfur based additive package. Assume the tech is just wrong here?


3) What does 4,000+ PPM Magnesium do for the transmission?


4) What does 900+ PPM Zinc Do for the transmission?


5) Does anybody have a lab analysis of the Mobil SHC-DC they can send or post up?


Thanks
 
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Seems kind of ghost townish here now that I've provided all the information, no answers to the question again.


Guess nobody on here knows nothing, must be magic fairy dust like I speculated earlier?


How about anyone have a VOC analysis on the Mobil delvac 1 synthetic transmission fluid 40?
 
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I can only add a couple of things:

ATF+4 in the G56. Since this was not the OEM spec fluid, the real question of ATF+4 is not "any proof it doesn't work?". The question is "any proof it does?". There is something incredibly lazy about doing such a radical change in fluid, without any mechanical modifications at all. This only becomes more ridiculous when you consider that ATF+4 is an oddball ATF where automatic transmissions are concerned. Way more wacky when it suddenly substitutes a commercial grade gear oil in a transmission Chrysler has zero to do with designing.

Forward bearing issue? Ridiculously common. This isn't even a theory anymore. Ask anyone who builds G56 transmissions about overfill in the G56, and you'll find this issue is real as it gets. Not a "mild hills terrain" issue. More like something that happens when pulling up an extended grade. Regardless, I wouldn't chance blowing a tranny bearing on not doing the overfill. I run the overfill in my G56, and I have no complaints or issues to speak of. This isn't one of those things that has lab tests behind it. Tranny builders noticed an issue, tried a trick to remedy it, and it's been working.

Speaking of things that have no lab tests and need trial and error. OP, if I were you, I would just back up to an overfill of ATF+4, or just try the Mobil 40. I'm not getting the feeling that beating up the VOAs is going to tell you anything about how a fluid is actually going to perform in your tranny. I'm happy with the Mobil 50, but it doesn't get colder than a witch's bosom in a brass brassiere down here either.
 
So you're getting notchy performance in fairly mild weather? I pretty much did a race start (in terms of how quickly I started the engine and left) out of my driveway a couple days ago in 48°F, and didn't have an issue. It was maybe, maybe a little tight. Maybe.

In that weather, I like to gear hold (without really romping on it, just run the gears out) to heat everything up nice. So I'm also probably not in the cold window too long.

Tried bleeding the system to make sure you are getting full clutch release? I had a truck that acted that way when it had a slave cylinder going south.
 
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