G56 fluid ?

[TRAMPLINEMAN]

When my truck had the original fluid in it, it shifted perfectly in any weather. I changed the fluid at 60K miles to Amsoil MTG. Now, when the weather is warm it shifts good, but not so much when it's cold. When it's cold you almost have to force it into gear or it will not go.

 

[AH64ID]

By OEM do you mean Ram or MB?

MB

If I remember correctly, MB specs Mobil SHC-MB which is no longer available in this country. Independent testing has confirmed that Delvac 50 is the closest oil meeting this spec that is currently available here.

- Ed

Testing by who?

Delvac 50 doesn't meet the specs that MB published, at least not from what MB has published.

All 4 specs that MB lists for the G56 are a GL-4 fluid. Delvac 50 is a MT-1 fluid (MT-1 is a HD non-synchro spec) and not a GL-4 fluid.

Delvac 50 is a bandwagon and most people jump off it fairly quickly.

When my truck had the original fluid in it, it shifted perfectly in any weather. I changed the fluid at 60K miles to Amsoil MTG. Now, when the weather is warm it shifts good, but not so much when it's cold. When it's cold you almost have to force it into gear or it will not go.

MTF or MTG?

I ask because that's how most reports of MTF are. MTF is the 5w-30 sychromesh fluid, also not the proper spec for the G56.

 

[Killgore]

Not to refute any claims, but the report can be read at -

http://www.carbonitecummins.com/Documents/Trans Oil Comparison.pdf

And yes, Mobil Delvac 50 is certified for GL-4 applications. But I hasten to add that I'm not grinding an axe just pointing out that some research has been done and I personally use it with no issues. Does my SBC growl? A little, but my horse use to snort just before he went to work.

- Ed

 

[TRAMPLINEMAN]

MTF or MTG?

I ask because that's how most reports of MTF are. MTF is the 5w-30 sychromesh fluid, also not the proper spec for the G56.

MTG. I haven't read up on it, but why is the original fluid no longer available in this country?

 

[RVTRKN]

I used SHC when it was available, didn't like it, and the gold flakes with just 500 miles in the oil was the reason for me changing it. MTG is to heavy for the G56 and helps it retain the heat when it gets hot. The OEM is ATF, and is just fine if you have a dual mass flywheel to soften the impact on gears. Remove the DMF and 50wt MTF seems to be the best answer that I have found. Were on our own to find the best oil after the DMF has been removed.

 

[RVTRKN]

When my truck had the original fluid in it, it shifted perfectly in any weather. I changed the fluid at 60K miles to Amsoil MTG. Now, when the weather is warm it shifts good, but not so much when it's cold. When it's cold you almost have to force it into gear or it will not go.

Because its to heavy, try 50wt and see how you like it when the weather gets cold.

 

[AH64ID]

Because its to heavy, try 50wt and see how you like it when the weather gets cold.

Ummm.... A 75w-90 gear oil is thinner than a SAE 50 oil when cold.

http://globalindustrialsolutions.net/viscosity-grade-chart.php

 

[AH64ID]

MTG. I haven't read up on it, but why is the original fluid no longer available in this country?

Honestly I don't think it's available anywhere anymore.

It wasn't the only fluid recommendation for the G56. There are 4 fluid specs listed by MB and a 75w-90 GL-4 is the best spec for any climate. There may be more data I am missing but I still haven't found any data on why the focus has been on a obsolete SAE 50wt oil.

 

[Killer223]

http://swepcolube.com/products/swepco-711-sae-50wt-synthetic-transmission-fluid

is what is currently in mine, it shifts very very smooth, as for this or the amsoil i had, i have to say this shifts a little smoother, with the amsoil i'd get partial grind heading into 3rd, with the 711 i do not.

Id have to say it's a toss up, both are great options.

 

[RVTRKN]

Ummm.... A 75w-90 gear oil is thinner than a SAE 50 oil when cold.

http://globalindustrialsolutions.net/viscosity-grade-chart.php

https://mobildelvac.com/en/automatic-transmission-fluids/mobil-delvac-1-transmission-fluid-50 Check this chart for the delvac 50wt and its slightly has a higher viscosity when 40*C but look up at 100*C and its way thinner than the gear oil. Also your comparing it to crank case oil in your chart.

 

[Regcabguy]

Ummm.... A 75w-90 gear oil is thinner than a SAE 50 oil when cold.

http://globalindustrialsolutions.net/viscosity-grade-chart.php

Based on experience I don't see how Delvac 50 or the Mobil fluid could be recommended for cooler/cold climates. In the brutal climate here it might hit *28 along the coast here it was very stiff. Killer223, the Swepco fluid sounds promising. I've always had the click upshifting 2-3.
I routinely drive half a block in 2nd

 

[Killgore]

EMAC2, Fred Easley, was the only source for Mobil-Trans SHC-MB that I am aware of, and then Mobil made a decision to get out of this market. Some suspect the Delvac 50 was and is the direct replacement; others would take exception to this statement. In the meantime, Fred who was an active contributor on this forum, developed the "death wobble" on his truck and the last time I talked with him several years ago had gotten rid of his ride. The test I cited by CarboniteCummins didn't include Amsoil unfortunately. It does show, rightly or wrongly, the correlation between Mobil-Trans SHC-MB and Delvac 50. When the day is done, most of us would agree that ATF is not the ideal fluid, especially when pulling heavy which most of us do. We are therefore left to our own devices and there are numerous alternatives out there. Chrysler, who is noted for short-cuts, especially on third-generation and before trucks, has dealt all of us a 'bad hand' that should rank up there with poor filtration and premature injector failures due to their ignoring Bosch and Cummins on the recommended primary filter specs. As I have said, I use the Delvac 50 and I am well satisfied. There are other alternatives and I certainly wouldn't say my decision is any better than anyone else's. I do go one step further and monitor transmission and differential temperatures and drive accordingly.

- Ed

 

[Newsa]

When the day is done, most of us would agree that ATF is not the ideal fluid, especially when pulling heavy which most of us do.
- Ed

Not the ideal fluid. Maybe?

But since the ATF is good enough for the Aisn and 68RFE (which pull loads at higher torque and ATF is their only lube), it is ADEQUATE for the G56 and the only one that preserves my Power Train and Max Care warranty.

 

[Newsa]

When the day is done, most of us would agree that ATF is not the ideal fluid, especially when pulling heavy which most of us do.
- Ed

Not the ideal fluid. Maybe?

But since the ATF is good enough for the Aisn and 68RFE (which pull loads at higher torque and ATF is their only lube), it is ADEQUATE for the G56 and the only one that preserves my Power Train and Max Care warranty.

 

[AH64ID]

Not the ideal fluid. Maybe?

But since the ATF is good enough for the Aisn and 68RFE (which pull loads at higher torque and ATF is their only lube), it is ADEQUATE for the G56 and the only one that preserves my Power Train and Max Care warranty.

Apples and Oranges... impossible to compare automatic transmissions to manual transmissions. That's like saying that hydraulic fluid is good enough for hydraulic pumps so it must be a good engine oil.

 

[Killgore]

Good point, John. And, I might also suggest reading the comments made by Blackstone Labs on their lab analysis of ATF+4. In short, they definitely recommend staying with the ATF+4 while under warranty. However, (and I copy and paste):

"Looking at the cSt Viscosity, you’ll notice it’s around 50% of the baseline. It is fair to say that ATF+4 is roughly half as thick as the recommended fluid. It does have more Boron, which means it has a better friction modifier package. However, all of detergents, AW, and EP additives are 1/3 of the baseline, with the exception of Zinc which is almost nonexistent. It’s half as thick and less than 1/3 as protective as MobilTrans SHC DC."

 

[Newsa]

Apples and Oranges... impossible to compare automatic transmissions to manual transmissions. That's like saying that hydraulic fluid is good enough for hydraulic pumps so it must be a good engine oil.

I agree. They are different. But Ram says ATF is ADEQUATE and since I have 14 months left on my power train warranty, I will only use red-colored fluid. Actually, I will used red-colored fluid for another 3+ years until my max care warranty has expired.

Good point, John. And, I might also suggest reading the comments made by Blackstone Labs on their lab analysis of ATF+4. In short, they definitely recommend staying with the ATF+4 while under warranty. However, (and I copy and paste):

"Looking at the cSt Viscosity, you’ll notice it’s around 50% of the baseline. It is fair to say that ATF+4 is roughly half as thick as the recommended fluid. It does have more Boron, which means it has a better friction modifier package. However, all of detergents, AW, and EP additives are 1/3 of the baseline, with the exception of Zinc which is almost nonexistent. It’s half as thick and less than 1/3 as protective as MobilTrans SHC DC."

Will Blackstone tell you what SAE weight is the equivalent of ATF? Is it equivalent to 20 wt? 30 wt? 40 wt?

I couldn't open the link

 

[AH64ID]

ATF is roughly a 75wt gear oil hot and cold.

 

[gtwitch]

If you want to see how ATF lubricates ,especially if there is any shear involved, put a tank full in your chain saw for chain lube and the chain will seize to the bar in very short order!!!! Done this (ran out of bar oil) and replaced the bar and got a new T shirt to prove it. that tells me a lot about the lubricating ability of ATF as it has a really high Shear Viscosity!! Only my thoughts on this Keep ATF in your auto transmissions!
gtwitch in wyoming

 

[RVTRKN]

Warranty is important, and if you are worried about warranty, that means your still running the DMF. The softening effect of the DMF compliments the ATF, however my bearings were browned from running very hot and were replaced at @35K miles at which time a SMF with the dual disk clutch was installed. If I could go back in time with what I have learned about the G56, I would have drained out the ATF at mile #3 and filled it with Mobil Delvac 50 and install my cooler setup. Also the DMF would remain intact until the clutch failed. My overheated bearings would not have been found if I had waited for the warranty to end, also other permanent damage probably would have eventually damaged it.