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

[2009ram2500]

Looking for some educated technical feedback not just who runs what or what they like opinions, please. I have a 2009 Dodge Ram 2500 with the manual G56 made by Mercedes Benz. Chrysler calls for ATF+4 in this trans which the viscosity is 35CsT at 40c/7.5CsT at 100c. I've read all of the threads on cumins forum and did a lot of research and found that Mercedes benz recommends Mobile Delvac synthetic trans fluid SAE 50 for this transmission but based on other users experience the Delvac 50 seemed to thick and caused hard or "notchy shifting" for many who tried it especially in cold weather (I'm in SoCal). So I researched a lot and found out that Amsoil Synchromesh 5W-30 and the Delvac 50 had similar base oils so I formulated my own mix of 3 qts Amsoil Synchromesh to 5 qts Mobile Delvac SAE 50 (This 3/5 blend's Viscosity is 88.76CsT at 40c / 14CsT at 100c) and I do have a custom side plate which is an extra 1/2 qt plus I over filled it 1 to 1.5 qts for a total of 7.5 to 8qts. After 25k on this Delvac/Synchromesh mix the shifting seemed to be getting harder so I read up again and the "new fix" seemed to be running the Amsoil Manual Transmission/transaxle severe gear lube 75/90 (MTG 75/90) (The Amsoil MTG is 87.6CsT at 40c/ 13.9CsT at 40c). So I dropped $125 on 8 qts of this and put it in. I've ran this now about 5k miles all 250-300 mile trips towing either a large boat (4k) or box trailer (7k) and I've noticed a few things running this oil VS. the Delvac/Synchromesh mix that i'd like to get some real answers to so I can decide to go back to Delvac/Synchromesh or keep the new MTG 75/90? I've noticed that the MTG 75/90 gets hot much faster, gets hotter over all, and when above 210F I can't shift even though the oils viscosity is much lighter when above 100c which is 204F. In fact I have to turn off the truck and restart it to get in to 2nd to start off a light etc when it's above 210F. I've also noticed that ambient tems effect how quickly the MTG gets hot by a lot. With the Delvac /Synchromesh combo making the same exact trip on the same road minus the trailer it took 200 miles to get to 180 degrees on a steady climb. Once at 180* it leveled off and didn't get much above that maybe 190* at 275 miles with ambient temps in the 100* range. Running the MTG I tracked the results making the same trip under the same load conditions and similar ambient temps Here are my temp/ miles results from my summer trips with the MTG 75/90: 30 miles to get to 140* 100 miles to get to 160* 140 miles to get to 180* And then it was a slow climb to 200* 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. So here's 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? Here's a link to my thread on this experiment on CF https://www.cumminsforum.com/forum/...elvac-50-amsoil-synchromesh-results.html Help, I'm lost in tranny land! Thanks

 

[StevieC]

I would PM MolaKule with these type of questions.

 

[mattwithcats]

Careful, some of the additives in motor oil (phosphorus) eat yellow metals. If that's a transmission that requires GL-4 fluid, I would be extremely careful...

 

[RooflessVW]

Originally Posted by mattwithcats

Careful, some of the additives in motor oil (phosphorus) eat yellow metals. If that's a transmission that requires GL-4 fluid, I would be extremely careful...

Here's not using motor oil, and the the manufacturer calls for ATF+4. Did you read the post? OP, you could try Mobil Delvac 1 75W-90. It is thinner than the 50 and should help with cold shifting. I also wouldn't mix oils.

 

[CT8]

Is the Delvac is a syncromesh fluid???? I thought is was for manual transmissions in class 8 vehicles.

 

[madeej11]

The other users aren't you. Try the Delvac 50 first since the problem is more prevalent with colder weather. If it doesn't work go with rooflessVW suggestion. I agree with him also about not mixing fluids.

 

[zeng]

Originally Posted by 2009ram2500

Looking for some educated technical feedback not just who runs what or what they like opinions, please. I have a 2009 Dodge Ram 2500 with the manual G56 made by Mercedes Benz. Chrysler calls for ATF+4 in this trans which the viscosity is 35CsT at 40c/7.5CsT at 100c. I've read all of the threads on cumins forum and did a lot of research and found that Mercedes benz recommends Mobile Delvac synthetic trans fluid SAE 50 for this transmission but based on other users experience the Delvac 50 seemed to thick and caused hard or "notchy shifting" for many who tried it especially in cold weather (I'm in SoCal). So I researched a lot and found out that Amsoil Synchromesh 5W-30 and the Delvac 50 had similar base oils so I formulated my own mix of 3 qts Amsoil Synchromesh to 5 qts Mobile Delvac SAE 50 (This 3/5 blend's Viscosity is 88.76CsT at 40c / 14CsT at 100c) and I do have a custom side plate which is an extra 1/2 qt plus I over filled it 1 to 1.5 qts for a total of 7.5 to 8qts. After 25k on this Delvac/Synchromesh mix the shifting seemed to be getting harder so I read up again and the "new fix" seemed to be running the Amsoil Manual Transmission/transaxle severe gear lube 75/90 (MTG 75/90) (The Amsoil MTG is 87.6CsT at 40c/ 13.9CsT at 40c). So I dropped $125 on 8 qts of this and put it in. I've ran this now about 5k miles all 250-300 mile trips towing either a large boat (4k) or box trailer (7k) and I've noticed a few things running this oil VS. the Delvac/Synchromesh mix that i'd like to get some real answers to so I can decide to go back to Delvac/Synchromesh or keep the new MTG 75/90? I've noticed that the MTG 75/90 gets hot much faster, gets hotter over all, and when above 210F I can't shift even though the oils viscosity is much lighter when above 100c which is 204F. In fact I have to turn off the truck and restart it to get in to 2nd to start off a light etc when it's above 210F. I've also noticed that ambient tems effect how quickly the MTG gets hot by a lot. With the Delvac /Synchromesh combo making the same exact trip on the same road minus the trailer it took 200 miles to get to 180 degrees on a steady climb. Once at 180* it leveled off and didn't get much above that maybe 190* at 275 miles with ambient temps in the 100* range. Running the MTG I tracked the results making the same trip under the same load conditions and similar ambient temps Here are my temp/ miles results from my summer trips with the MTG 75/90: 30 miles to get to 140* 100 miles to get to 160* 140 miles to get to 180* And then it was a slow climb to 200* 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. So here's 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?

There is negligible difference in viscosity related drag friction/drag heat from both systems . However the culprit is in significant differences in frictional heat generation in sliding motions of gearing pairs and bearings between the two . Amsoil MTF 75W90 GL4 doesn't carry any friction-reducing solid lubricants such as Moly/Boron/Titanium , hence producing 'normal' amount of frictional heat depending on operating viscosity (and hence operating temperatures) and operating loads. Whereas Delvac Transmission 50 (MT-1) part of the mixture is likely to carry a certain amount of solid lubricants such as Moly/Boron/Titanium , hence reducing frictional heat generation and improving FE. A VOA/UOA of Delvac 50 (or its mixture) may help establish my speculation or otherwise. I'm not sure if Amsoil Synchromesh carries any friction-reducing Moly/Boron/Titanium though .

Originally Posted by 2009ram2500

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)?

Smooth engagement of manual trans synchros is heavily influenced by the ratio of Dynamic/Static Coefficients of Friction of fluid systems and it is influenced by varying temperatures. Hence , add packs of certain MTF fluids that is working perfectly well in most manual trans would behave annoyingly in a manual trans or two. Besides it often times behaves funnily in the same fluid system operating at different temperature regimes.

Originally Posted by 2009ram2500

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? Help, I'm lost in tranny land! Thanks

Of course it is ...........to achieve minimum or lowest possible 'high' operating temperature regimes , in all lubrication systems be it in manual/auto/CVT transmissions , axle differentials or engines ....... primarily to retain adequate/high protective MOFT and to simultaneously promote lubricants longevity, mineral or synthetics.

 

[2009ram2500]

Thank you Zeng for a intelligent educated answer though I'm not sure we're talking about the same Amsoil product. You specd MTF above and I used MTG, see below links. Please update your post if the MTG has different additives than the MTF you referred to above. Here are some pictures and links to what I'm using hopefully this will put an end to the confusion. Click the links below to get manufacturer datasheets etc Mobile Delvac Synthetic Transmission Fluid 50 Amsoil Synchromesh 5W-30 Amsoil Manual Transmission & Transaxle Gear Lube 75-90

 

[2009ram2500]

MolaKule to the courtesy phone please I could really use some intelligent help with this. Thank You

 

[Killer223]

valvoline has a good GL4, and i like the swepco711 in my g56.

 

[zeng]

Originally Posted by 2009ram2500

Thank you Zeng for a intelligent educated answer though I'm not sure we're talking about the same Amsoil product. You specd MTF above and I used MTG, see below links. Please update your post if the MTG has different additives than the MTF you referred to above. Here are some pictures and links to what I'm using hopefully this will put an end to the confusion. Click the links below to get manufacturer datasheets etc Mobile Delvac Synthetic Transmission Fluid 50 Amsoil Synchromesh 5W-30 Amsoil Manual Transmission & Transaxle Gear Lube 75-90

Yes, we're referring to the same Amsoils. Your MTG is my MTF GL4.

 

[zeng]

Got it, Mobil Delvac Transmission Fluid 50 MT-1 has 267 ppm Boron.

 

[MolaKule]

The other sites will have you running around in circles. You should have done a VOA of your mix to determine the resulting viscosity. I suspect it is way too high. Chrysler required an ATF+4 for improved cold weather shifting with a viscosity at 100C of 7,5 cST, which is the viscosity of non-LV ATF's. The Delvac's application is primarily for HD OTR transmissions, is speced for 17.5 [email protected], and I don't see any approvals for your transmission listed. The Amsoil MTF has a viscosity at 100C of ~ 9.4 cST and contains the required friction modifiers for synchro assemblies. I recommend you use the Amsoil MTF ALONE and thoroughly drain your tranny of the current mix.

 

[2009ram2500]

All of the information your telling me to get in in the 1st post.

Originally Posted by MolaKule

You should have done a VOA of your mix to determine the resulting viscosity. I suspect it is way too high.

"I formulated my own mix of 3 qts Amsoil Synchromesh to 5 qts Mobile Delvac SAE 50 (This 3/5 blend's Viscosity is 88.76CsT at 40c / 14CsT at 100c"

Originally Posted by MolaKule

The Delvac's application is primarily for HD OTR transmissions, is speced for 17.5 [email protected], and I don't see any approvals for your transmission listed.

"Mercedes benz specs Mobile Delvac synthetic trans fluid SAE 50 for this transmission" The tranny maker specs this oil for this trans.

Originally Posted by MolaKule

The Amsoil MTF has a viscosity at 100C of ~ 9.4 cST and contains the required friction modifiers for synchro assemblies.

I'm not running a mix right now I'm running the MTG. Also Synchromesh & ATF is too thin for gear protection pulling heavy loads like I do. The only reason Chrysler did not spec Delvac 50 for the G56 is they didn't want to spend millions of dollars re-rigging their production lines so they threw ATF+4 in it as they use it for just about everything else on these trucks BUT ATF+4 is NOT what the actual tranny maker specs. The MTG's heating issue is NOT the viscosity as again I've ran 2 different oils in this trans the 3/5 synchromesh/Delvac 50 mix and the Amsoil MTG with almost the exact same viscosity and the 3/5 Synchromesh/Delvac mix took longer to get to max temp of 180 to 190F where the MTG gets hot in shorter distances and maxes out at a higher temp 220F..

Originally Posted by MolaKule

I recommend you use the Amsoil MTF ALONE and thoroughly drain your tranny of the current mix.

This does not answer the questions I posed, it's just an opinion with out all of the information and I'm looking for real answers so I can make an informed decision what I want to run. The heating differences between the two is NOT viscosity since both oils where the same, it's gotta be additives and/or physical make up?. 3/5 Synchromesh/Delvac Blend: 88.76CsT at 40c / 14CsT at 100c Amsoil MTG: 87.6CsT at 40c/ 13.9CsT at 40c

 

[02SE]

Why are you overfilling? The Mercedes engineers didn't set the fill level arbitrarily. Every manual trans I've ever built ran best at the proper fill level, with the proper oil in it.

 

[MolaKule]

Quote

This does not answer the questions I posed, it's just an opinion with out all of the information and I'm looking for real answers so I can make an informed decision what I want to run. The heating differences between the two is NOT viscosity since both oils where the same, it's gotta be additives and/or physical make up?.

It is a suggestion based on Formulating MTF oils.

Originally Posted by MolaKule

...Chrysler required an ATF+4 for improved cold weather shifting with a viscosity at 100C of 7,5 cST, which is the viscosity of non-LV ATF's. The Delvac's application is primarily for HD OTR transmissions, is speced for 17.5 [email protected], and I don't see any approvals for your transmission listed. The Amsoil MTF has a viscosity at 100C of ~ 9.4 cST and contains the required friction modifiers for synchro assemblies. I recommend you use the Amsoil MTF ALONE and thoroughly drain your tranny of the current mix.

What I recommended was to use AMSOIL MTF alone which has a viscosity at 100C of ~ 9.4 cST. What I am trying to convey to you is I do think your resulting mix has too high a viscosity AND not enough of the proper friction modification chemistry. You're diluting the proper friction modification chemistry with the Delvac fluid.

 

[4WD]

Mobil D1 has a 40 as well

 

[2009ram2500]

Does anybody have a Blackstone Volatile Organic Analysis (VOA) on the Amsoil Manual Synchromesh Transmission Fluid 5W-30 AND the Amsoil Manual Transmission and Transaxle 75W-90 they could email, post up, or have a link to? I'd be real interested to see what the chemical make up of these are compared to the Delvac Transmission 50. Thanks

 

[4WD]

This comes full circle to the Delvac ??? http://carbonitecummins.com/Documents/Trans%20Oil%20Comparison.pdf

 

[MolaKule]

You'll never know the total chemical makeup with a $28.00 analysis. AMSOIL MTF PDB