Dealer put gear oil in transfer case
- Thread starter lobo11
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Yeah, it sounds like -46C is the crossover. Amsoil ATF is less viscous below that point and the ATF+4 is less viscous above that point.
dnewton3
Staff member
This reminds me of the big debate in the GM HD truck world about whether to use the spec'd ATF or 5w-30 motor oil in the chain drive 261/263 t-case.
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
I would beg to differ. Most of you know me; I just could not accept that lame excuse. So I contacted the guy directly and had a one-on-one conversation. I asked all kinds of questions about lubricity, detergents, viscosities, shear-points, film strength, Noack volatility, etc. The guy could not answer one single question satisfactorily. In short, it was clear to me that he simply was of the "thicker is better" crowd, and had done zero research into his suggestion. And he is a supposed "expert" in the field.
Further, he gave no thought to the REAL root cause. If a t-case is dry, it's because someone didn't do the proper preventative checks on a timely basis. Someone didn't change, or at least top-off, the fluids on a reasonable schedule. HOW IS THAT THE FAULT OF ANY FLUID? How is the lubricant to blame when the negligence of the owner was the true root cause? If we were to allow the engine oil to burn away in our diesel truck engine, and never check the dipstick, would we all accept blaming Delo, Delvac or Rotella for the event? Would we suggest running a 140-weight gear oil in the crankcase instead of 15w-40 HDEO? PREPOSTEROUS!
To be fair, of all the guys that do run 5w-30 in their t-case, I've not heard of any significant failures, so it's probably a benign (albiet stupid) suggestion. And, from those who have tried it, they do report much more difficulty in shifting the t-case when really cold outside; typically makes sense because the motor oil is generally "thicker" than ATF at really cold temps.
And so goes this topic here. The dealer swapped fluids, I suspect, in some vain and lame attempt to avert a condition that is easily addressed with simple maintenance. And to boot, their sorry "synthetic" excuse does not hold water when just about any decent ATF forumla is available in a synthetic version.
Will the gear oil work in this application? Probably so. Will it help? Probably not. Will it hurt? Possibly not.
But why not just use the spec'd fluid, keep the fluid at recommended levels, and not overthink this?
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
I would beg to differ. Most of you know me; I just could not accept that lame excuse. So I contacted the guy directly and had a one-on-one conversation. I asked all kinds of questions about lubricity, detergents, viscosities, shear-points, film strength, Noack volatility, etc. The guy could not answer one single question satisfactorily. In short, it was clear to me that he simply was of the "thicker is better" crowd, and had done zero research into his suggestion. And he is a supposed "expert" in the field.
Further, he gave no thought to the REAL root cause. If a t-case is dry, it's because someone didn't do the proper preventative checks on a timely basis. Someone didn't change, or at least top-off, the fluids on a reasonable schedule. HOW IS THAT THE FAULT OF ANY FLUID? How is the lubricant to blame when the negligence of the owner was the true root cause? If we were to allow the engine oil to burn away in our diesel truck engine, and never check the dipstick, would we all accept blaming Delo, Delvac or Rotella for the event? Would we suggest running a 140-weight gear oil in the crankcase instead of 15w-40 HDEO? PREPOSTEROUS!
To be fair, of all the guys that do run 5w-30 in their t-case, I've not heard of any significant failures, so it's probably a benign (albiet stupid) suggestion. And, from those who have tried it, they do report much more difficulty in shifting the t-case when really cold outside; typically makes sense because the motor oil is generally "thicker" than ATF at really cold temps.
And so goes this topic here. The dealer swapped fluids, I suspect, in some vain and lame attempt to avert a condition that is easily addressed with simple maintenance. And to boot, their sorry "synthetic" excuse does not hold water when just about any decent ATF forumla is available in a synthetic version.
Will the gear oil work in this application? Probably so. Will it help? Probably not. Will it hurt? Possibly not.
But why not just use the spec'd fluid, keep the fluid at recommended levels, and not overthink this?
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Correct, the crossover point is indeed -46C, from that point out the Amsoil is less viscous. However, I should also note the slope of the viscosity curve between the two increases pretty significantly as well, where before -46 the slope of the two viscosity tracks almost perfectly. I would guess this is where the difference in grp III vs. IV shows itself--but that is darn cold regardless.
Originally Posted By: dnewton3
This reminds me of the big debate in the GM HD truck world about whether to use the spec'd ATF or 5w-30 motor oil in the chain drive 261/263 t-case.
...
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
Mike Weinberg of RSG suggested the original ATF oil specified by the OE was being aerated by the drivechain/geartrain in certain transfer case applications. This aerated mist then could be exhausted via the vent and slowly drop in level. I have observed residue at vents consistent with his speculation. I can imagine the OEs were attracted to the ATF everywhere in drivetrain for fuel efficiency and cost.
The Mazda 5 speeds used in the Rangers and B-series pickups (MR5OD) were prone to aerated ATF and leaks at the top of the shifter level cover. Seepage at the original shrinking shift rail plugs was very common. Lube failure was common due to these problems (and lack of inspection).
We continue to use 5w30 motor oil in certain transfer case applications in our shop without any problems in our service and warranty work. It's just fine in some cases and transmissions as you suspect.
You're right all these problems could be identified with regular and routine inspection, but the transfer case is often overlooked during most work. If it's not making noise or leaking, a lot of shops and techs will not check the level.
To the OP, I would remove the dealer installed fluid and install the ATF+4 for best operation on this specific transfer case (AWD style).
This reminds me of the big debate in the GM HD truck world about whether to use the spec'd ATF or 5w-30 motor oil in the chain drive 261/263 t-case.
...
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
Mike Weinberg of RSG suggested the original ATF oil specified by the OE was being aerated by the drivechain/geartrain in certain transfer case applications. This aerated mist then could be exhausted via the vent and slowly drop in level. I have observed residue at vents consistent with his speculation. I can imagine the OEs were attracted to the ATF everywhere in drivetrain for fuel efficiency and cost.
The Mazda 5 speeds used in the Rangers and B-series pickups (MR5OD) were prone to aerated ATF and leaks at the top of the shifter level cover. Seepage at the original shrinking shift rail plugs was very common. Lube failure was common due to these problems (and lack of inspection).
We continue to use 5w30 motor oil in certain transfer case applications in our shop without any problems in our service and warranty work. It's just fine in some cases and transmissions as you suspect.
You're right all these problems could be identified with regular and routine inspection, but the transfer case is often overlooked during most work. If it's not making noise or leaking, a lot of shops and techs will not check the level.
To the OP, I would remove the dealer installed fluid and install the ATF+4 for best operation on this specific transfer case (AWD style).
Ok so this is what I got from my Rheometer runs: Amsoil Universal ATF compared to the BG fluid (used since I do not plan on using, so I did not purchase). The difference really starts to show up at about -10C where the delta in the viscosity really starts to increase at a significantly higher rate with the BG gear lube. It is very noticable when graphing the two against each other.
20C BG 1.6x higher viscosity
0C BG 1.67x higher viscosity
-10C BG 1.72x higher viscosity
-20C BG 1.8x higher viscosity
-30C BG 2.4x higher viscosity
-40C BG 3x higher viscosity
-50C BG 3.6x higher viscosity
My plan now is to check the viscosity of the ATF fluid aobut 4-6 weeks from now to see if it is shear thinning a bunch or not. However, regardless I have already noticed a significant difference with the ATF in the TC. Definietly smoother and less sluggish at low temperature, but the best thing is--with the old fluid I used to get ( more pronounced & often when cold, but still noticible at times when warm),a shudder that would occur when I would accelerate (say a short distance) then release the accelerator to coast a bit before applying the brake. I have not experienced this shudder since the change over, and overall I am very pleased with the switch at this point. I am seriously considering submitting the BG fluid for a UOA since there seems to be such a difference in the driveline response with the change. I will keep updating impressions and any new data as I get it.
20C BG 1.6x higher viscosity
0C BG 1.67x higher viscosity
-10C BG 1.72x higher viscosity
-20C BG 1.8x higher viscosity
-30C BG 2.4x higher viscosity
-40C BG 3x higher viscosity
-50C BG 3.6x higher viscosity
My plan now is to check the viscosity of the ATF fluid aobut 4-6 weeks from now to see if it is shear thinning a bunch or not. However, regardless I have already noticed a significant difference with the ATF in the TC. Definietly smoother and less sluggish at low temperature, but the best thing is--with the old fluid I used to get ( more pronounced & often when cold, but still noticible at times when warm),a shudder that would occur when I would accelerate (say a short distance) then release the accelerator to coast a bit before applying the brake. I have not experienced this shudder since the change over, and overall I am very pleased with the switch at this point. I am seriously considering submitting the BG fluid for a UOA since there seems to be such a difference in the driveline response with the change. I will keep updating impressions and any new data as I get it.
lobo11,
Nice data and thanks for the followup. Do you know the model of the transfer case in your vehicle? Looks like it should be a New Venture NV244 case. If this is the right transfer case, it uses a gear differential to provide the torque split to front and rear output shafts for AWD operation. Viscosity will likely have effects on operation.
Nice data and thanks for the followup. Do you know the model of the transfer case in your vehicle? Looks like it should be a New Venture NV244 case. If this is the right transfer case, it uses a gear differential to provide the torque split to front and rear output shafts for AWD operation. Viscosity will likely have effects on operation.
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dnewton3
Staff member
Originally Posted By: FazerZ
Originally Posted By: dnewton3
This reminds me of the big debate in the GM HD truck world about whether to use the spec'd ATF or 5w-30 motor oil in the chain drive 261/263 t-case.
...
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
Mike Weinberg of RSG suggested the original ATF oil specified by the OE was being aerated by the drivechain/geartrain in certain transfer case applications. This aerated mist then could be exhausted via the vent and slowly drop in level. I have observed residue at vents consistent with his speculation. I can imagine the OEs were attracted to the ATF everywhere in drivetrain for fuel efficiency and cost.
The Mazda 5 speeds used in the Rangers and B-series pickups (MR5OD) were prone to aerated ATF and leaks at the top of the shifter level cover. Seepage at the original shrinking shift rail plugs was very common. Lube failure was common due to these problems (and lack of inspection).
We continue to use 5w30 motor oil in certain transfer case applications in our shop without any problems in our service and warranty work. It's just fine in some cases and transmissions as you suspect.
You're right all these problems could be identified with regular and routine inspection, but the transfer case is often overlooked during most work. If it's not making noise or leaking, a lot of shops and techs will not check the level.
To the OP, I would remove the dealer installed fluid and install the ATF+4 for best operation on this specific transfer case (AWD style).
Yes, and to go further, this is where I simply don't understand why people don't think their way through an issue.
In those t-cases, the factory fill was the old DexIII fluid (at least up until the Dex VI came out). That DEXIII was a mineral based fluid. The areation and evaporation of that fluid might well have been a concern. But the knee-jerk reaction to 5w-30 was completely a shade-tree guess by Mike. I know because I communicated with him directly. I also spoke directly with a team project engineer at Magna (formerly NV) who worked on that t-case design. ATF is the properly spec'd fluid for those t-cases.
And here is where I don't understand where most folks veer off course. There are MANY decent Dex/Merc type products that are available in synthetic form (Mobil 1, Amsoil, etc). If evaporation and aeration resistance were the goal, rather than switch to a untried and unproven motor oil, why not just suggest using a synthetic version of the old DEX/Merc fluid? Why was Mike's first reaction to move to an engine oil? In fact, he never mentioned that a synthetic engine oil should be used, but only a 5w-30 engine oil be used. Why not suggest upgrading to a quality PAO synthetic ATF, versus a conventional engine oil? Why not stay with the proper fluid spec's, and not suggest something that he only swag'd?
I made up my mind after conversing with him and Magna; ATF is the proper fluid to be used. That does not mean that engine oil does not work; it does. There are lots of units out there that run engine oil, and don't have reported issues.
Just so the data is clear, here is the link to the article in question: http://www.rsgear.com/articles/2007_03.pdf
Now, in that article, he not only suggests to use motor oil in place of the ATF, but he also advises people to overfill the t-case, via the VSS hole, with an additional quart (using 3 qts instead of the spec'd 2 qts). That is a 50% overfill! If any of you know much about gear-cases, overfilling can result in the very problems you're trying to avoid! Overfilling can result in aeration and excess splashing, thereby venting fluid that should not be vented. How silly is that? And, nowhere did he suggest to use synthetic motor oil. And his final suggestion? Have the customer check the fluid level every 5k miles, and change the fluid every 10k miles. WHAT???? If the owner is capable of doing that, then why suggest using motor oil in the first place? Is it his assertion that ATF cannot even last 5k miles in the t-case, and that only way to keep the fluid level in the acceptable range is to use motor oil changed every 10k miles? PREPOSTEROUS!
Would not a good PAO synthetic ATF with the proper volume not be a "better" choice than a improperly spec'd motor oil with 50% overfill if areation and evaporation were your concern?
This topic is first and foremost about the failures of cases from neglect; it's not fair to blame any fluid for the lack of volume in the sump.
Want aomw grand irony? Read on ...
Here's the same topic from the other end of the spectrum. The HD faithful (Harley-Davidson) folks are to use what equates to engine oil in their primary drive cases. And in the search of something "better", many of them run ATF instead. Now, consider that the primary chain drive system in the Harley primary drive system is VERY similar to the chain drive system in the t-case, and think this all the way around in it's full circular reference.
So, I draw a few conclusions in this entire debate:
1) The grass is always greener on the other side of the chain-driven pasture. HD motorcycle folks want to use ATF because they perceive that ATF is better than motor oil; Chevy truck guys want to use motor oil because someone told them it's "better" than ATF ... Irony at it's finest.
2) Since there are a lot of examples of people using both the correct and improperly spec'd fluids, and very few (if any) examples of failures, it's generally a moot point about fluid choice in these applications. What's FAR MORE IMPORTANT is to keep the fluid level in the acceptable range, regardless of the fluid used.
3) RSG simply swag'd a guess, and offered a rudimentary "thicker is better" suggestion with no research whatsoever, and then advised folks to over-fill a gear case, thereby contributing to a condition they were trying to avoid in the first place.
Originally Posted By: dnewton3
This reminds me of the big debate in the GM HD truck world about whether to use the spec'd ATF or 5w-30 motor oil in the chain drive 261/263 t-case.
...
In that topic, the entire debate stems from an article where the owner of RSG suggested doing such because he felt the ATF would boil out and leave the t-cases dry. They had reman'd some cases and suspected that this was the root cause.
Mike Weinberg of RSG suggested the original ATF oil specified by the OE was being aerated by the drivechain/geartrain in certain transfer case applications. This aerated mist then could be exhausted via the vent and slowly drop in level. I have observed residue at vents consistent with his speculation. I can imagine the OEs were attracted to the ATF everywhere in drivetrain for fuel efficiency and cost.
The Mazda 5 speeds used in the Rangers and B-series pickups (MR5OD) were prone to aerated ATF and leaks at the top of the shifter level cover. Seepage at the original shrinking shift rail plugs was very common. Lube failure was common due to these problems (and lack of inspection).
We continue to use 5w30 motor oil in certain transfer case applications in our shop without any problems in our service and warranty work. It's just fine in some cases and transmissions as you suspect.
You're right all these problems could be identified with regular and routine inspection, but the transfer case is often overlooked during most work. If it's not making noise or leaking, a lot of shops and techs will not check the level.
To the OP, I would remove the dealer installed fluid and install the ATF+4 for best operation on this specific transfer case (AWD style).
Yes, and to go further, this is where I simply don't understand why people don't think their way through an issue.
In those t-cases, the factory fill was the old DexIII fluid (at least up until the Dex VI came out). That DEXIII was a mineral based fluid. The areation and evaporation of that fluid might well have been a concern. But the knee-jerk reaction to 5w-30 was completely a shade-tree guess by Mike. I know because I communicated with him directly. I also spoke directly with a team project engineer at Magna (formerly NV) who worked on that t-case design. ATF is the properly spec'd fluid for those t-cases.
And here is where I don't understand where most folks veer off course. There are MANY decent Dex/Merc type products that are available in synthetic form (Mobil 1, Amsoil, etc). If evaporation and aeration resistance were the goal, rather than switch to a untried and unproven motor oil, why not just suggest using a synthetic version of the old DEX/Merc fluid? Why was Mike's first reaction to move to an engine oil? In fact, he never mentioned that a synthetic engine oil should be used, but only a 5w-30 engine oil be used. Why not suggest upgrading to a quality PAO synthetic ATF, versus a conventional engine oil? Why not stay with the proper fluid spec's, and not suggest something that he only swag'd?
I made up my mind after conversing with him and Magna; ATF is the proper fluid to be used. That does not mean that engine oil does not work; it does. There are lots of units out there that run engine oil, and don't have reported issues.
Just so the data is clear, here is the link to the article in question: http://www.rsgear.com/articles/2007_03.pdf
Now, in that article, he not only suggests to use motor oil in place of the ATF, but he also advises people to overfill the t-case, via the VSS hole, with an additional quart (using 3 qts instead of the spec'd 2 qts). That is a 50% overfill! If any of you know much about gear-cases, overfilling can result in the very problems you're trying to avoid! Overfilling can result in aeration and excess splashing, thereby venting fluid that should not be vented. How silly is that? And, nowhere did he suggest to use synthetic motor oil. And his final suggestion? Have the customer check the fluid level every 5k miles, and change the fluid every 10k miles. WHAT???? If the owner is capable of doing that, then why suggest using motor oil in the first place? Is it his assertion that ATF cannot even last 5k miles in the t-case, and that only way to keep the fluid level in the acceptable range is to use motor oil changed every 10k miles? PREPOSTEROUS!
Would not a good PAO synthetic ATF with the proper volume not be a "better" choice than a improperly spec'd motor oil with 50% overfill if areation and evaporation were your concern?
This topic is first and foremost about the failures of cases from neglect; it's not fair to blame any fluid for the lack of volume in the sump.
Want aomw grand irony? Read on ...
Here's the same topic from the other end of the spectrum. The HD faithful (Harley-Davidson) folks are to use what equates to engine oil in their primary drive cases. And in the search of something "better", many of them run ATF instead. Now, consider that the primary chain drive system in the Harley primary drive system is VERY similar to the chain drive system in the t-case, and think this all the way around in it's full circular reference.
So, I draw a few conclusions in this entire debate:
1) The grass is always greener on the other side of the chain-driven pasture. HD motorcycle folks want to use ATF because they perceive that ATF is better than motor oil; Chevy truck guys want to use motor oil because someone told them it's "better" than ATF ... Irony at it's finest.
2) Since there are a lot of examples of people using both the correct and improperly spec'd fluids, and very few (if any) examples of failures, it's generally a moot point about fluid choice in these applications. What's FAR MORE IMPORTANT is to keep the fluid level in the acceptable range, regardless of the fluid used.
3) RSG simply swag'd a guess, and offered a rudimentary "thicker is better" suggestion with no research whatsoever, and then advised folks to over-fill a gear case, thereby contributing to a condition they were trying to avoid in the first place.
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I have read and posted in the thread at Diesel Place forum on transfer case fluids. I have TES 295 in mine, two quarts.
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