Dealer put gear oil in transfer case

[lobo11]

So basically I bought a 2001 AWD 4.7L Durango from my father-in-law. I have a service record spreadsheet that I made up from his receipts and it came up that the transfer case needed to be drained and filled. According to the owners manual the TC needs ATF+4 transmission fluid. I crawl under the Durango and almost break an T wrench undoing the plug only to find instead of the unique odor and thin viscosity of ATF+4 greeting me the thick viscosity and sulfur odor of a gear lube, probably based on looks a 75w-90. Needless to say I am suprised and a little concerned. i contacted teh dealer who did this and here is their response--

THE FLUID THAT WAS USED WHEN WE CHANGED IT WAS A BG PRODUCT CALLED SYNCRO SHIFT SYNTHETIC TRANSFER CASE FLUID (WHICH WE SELL IN OUR PARTS DEPARTMENT ) FROM THE FACTORY IT HAS ATF.
SO IN ANSWER TO YOUR QUESTION YOU CAN USE EITHER BUT FROM MY TECHNICIANS OPINION IS IT WAS CHANGED TO SYTHETIC SO HE WOULD RECOMMEND STICKING WITH SYNTHETIC.
THANK YOU

I am a little [censored] off that the dealer felt it was ok to put gear lube in a TC that called for ATF. The fluid has been in there for almost 25K miles with no "apparent" issues. What would you'all do if you were me?
Thanks, Ben.

 

[JHZR2]

Put in the spec fluid and not worry.

 

[Bottom_Feeder]

^ What he said.

What else can you do? Sue the dealer? Just dump it for the correct lube and move on.

 

[Donald]

How critical is the transfer case? A few gears and a big chain?

Does your vehicle have a shift level for the transfer case?

 

[SwampSurvivor]

As long as it's just a mechanical transfer case - not one of the ones with a viscous clutch, you should be OK.

 

[mechtech2]

They should have let you know. Really.
But that new fluid may prove to be superior, so I'd leave it in there.

 

[andyd]

I would find out more about the product. It maybe fine. On the face of it. I wouldn't be happy.

 

[Tempest]

Quote:
BG Syncro Shift II Synthetic Gear Lubricant
specifically formulated for modern manual transmissions, transaxles and transfer cases. It provides exceptional thermal stability along with outstanding extreme pressure characteristics, shear stability and low temperature fluidity. BG Syncro Shift II may be effectively used in all vehicles where engine oil, ATF or GL-4 gear oil is specified as "service fill" for manual transmissions.
SAE 75W-80 API GL-4
Made in USA

http://www.flatironstuning.com/p-1422-bg-syncro-shift-ii-manual-transmission-fluid.aspx

I would leave it in pending low temp flow specs.

 

[lobo11]

It is not a cold weather lover for sure, I wonder how much of it could be related to a 75 wieght oil compared to an ATF that is a much lower viscosity. This is one of the only years the Durango was offered in AWD and it is AWD so I assume the transfer case is always engaged??

 

[lobo11]

It does not have a shift lever for the case, just a selector knob AWD, 4Hi, and 4Lo. I have never had AWD before, so I am not sure if normal, but there is a very big difference in the AWD and the 4Hi. The AWD is nice, but if the roads are bad the 4Hi makes the Durango drive like a tank. I have been through some pretty significant snow depths without the old girl stuttering even a bit. I was thinking of draining and filling with ATF+4 and running for a week or so to get the residual gear lube incorporated, then draining again and filling with ATF+4 or some Amsoil universal ATF I have. I figure winter would be a good time for me to see if I see or really feel a difference between the gear lube and the ATF. Thoughts? Most ATFs are pretty low viscosity so this whole thing makes so little sense to me.

 

[SubLGT]

If it is AWD, it must have some type of center differential. What type is it? Viscous? Torsen? Clutch? Other?

 

[tdi-rick]

Originally Posted By: SubLGT
If it is AWD, it must have some type of center differential. What type is it? Viscous? Torsen? Clutch? Other?


You forgot the most obvious, open.

I can't see a 75W-90 gear oil being a problem and is what I've run for the last ten years in our one and only chain drive t/case. (Nissan Patrol)

 

[RiceCake]

Originally Posted By: lobo11
IT WAS CHANGED TO SYTHETIC SO HE WOULD RECOMMEND STICKING WITH SYNTHETIC


So, ironically enough, you can use ATF+4 if you want, since its synthetic.

The gear oil will likely hamper MPG being thicker. I'd use ATF+4 personally because its a pretty rugged ATF. I'd consider their arbitrary, untested substitution their way of saying they just bought you a transfer case warranty.

Edit: http://www.kansasbg.com/Complete_Set_of_Spec_and_Tech/0792.pdf

VI of 149 is far less then say, Mobil 1 Super ATF+4 (VI of 200). Also cold pumping of this gear oil is 46,175 cP at -40, versus Mobil 1 Super ATF+4, at a thin 8,800 cP. This fluid is a little thicker at 40C, 45.52 cSt then ATF+4, 34.4 cSt. At 100C its a little thicker too, but not by much. 8.0 cSt for the gear oil, 7.5 cSt at 100C for ATF+4. The ATF+4 beats its pour point at -50, seven degrees better.

I'd use ATF+4.

 

[lobo11]

I have no idea what type it is.

I made a spreadsheet of the Technical Specs. of the BG vs. Mobil Super ATF+4, another 75W-90 Syntheic gear lube for manual transmissions, Mobil 1 Synthetic ATF, and Amsoil Synthetic Multi-Vehicle Transmission fluid. From that sheet this BG product must have a ton of viscosity modifiers in it, otherwise I see no possible way it can meet the viscosity it specs. at 40C and still have the viscosity profile it gives from low to high tmperature. In addition I have had this stuff in between my fingers at 23-25C and it shows little difference in comparisson to the Severe gear 75w-90 I have in my differentials. To be honest the low temperature viscosity is what is worrisome to me especially if it is loaded with modifiers like I suspect. Looking at the spreadsheet I made I am thinking of going with the Mobil Super ATF+4 or the Mobil 1 Synthetic ATF fluid for the winter and see how it responds.

 

[Jim Allen]

Syncho Shift is good stuff. Or at least it was when I used it in all my chain drive transfer cases and a passle of customer transfer cases back in the '90s. It solved a very real problem in Range Rover BW full-time transfer cases, namely overheating and cooking the oil. They had a 30K OCI on the t-case oil those rigs back then and when you dumped the ATF, it was jet black and malodorous... clearly used up. We starting doing the OCI at 15K and the oil was not quite so wasted. The issue was the t-case, of course, not the oil, but the Synchro Shift solved the problem and we were able to run 60K intervals.

Despirte the fact that the Synchro Shift is a higher viscosity than ATF, it seemed to reduce friction. I was able to test the fluid on a dyno by putting a Range Rover on with Dex III on a 4-sheel dyno, measure the wheel power with fresh Dex III, then doing a switch to Synchro Shift and with the temp stabilized, the Synchro shift allowed the Rover to put more power to the ground. We also noted about a 40 degree decrease in oil temp.. which was the issue withe Dex III. The Synchro Shift reduced oil temps and was also better able to withstand the higher temps of the Rover full-time t-case.

Viscosity is more an issue in a full-time t-case than a part time but is the Durango truly AWD, meaning fulltime operation with a center differential, or is it Automatic 4wd where engagement of the front axle is electronically applied? If it truly is AWD/full-time 4wd, then you MIGHT see a slight increase in powertrain drag in a cold climate.

SInce BG rates it as safe for t-cases in general, I don't think you have to worry about your Durango, nor chastise the dealer over installing it in the first place. I haven't used ATF in any of my chain drive t-cases for decades. I have used either the BG, tractor THF, or RP Synchro Max (which is a similar product to the BG Synchro Shift). All of these are more robust lubricants than ATF with more gear type additives that, I believe, add life and durability to a transfer case. In a part-time t-case, the increased viscosity is not an issue because next to nothing is turning in the t-case in 2wd. As I said, a full-time case might see an increase in drag in cold weather. Not sure how much a difference it will make.

The Mobil ATF+4 vs BG

cSt @ 40- 34.4/45.52
cSt @ 100- 7.5/8.0

The CCS of the Mobil is good at 8,800 cP but isn't directly comparable to the MRV spec given for the BG 46,175. I get rough numbers comparing the two by dividing MRV by 4, which yields 11,500 cP in this casefor the BG. Don't know how accurate that is but I discovered that when I had both specs on the same oil and it worked out.

 

[lobo11]

You know what I am going to put this to a test. I have access at work to a viscometer with temperature control. I will pull some of the BG sutff and run it apples to apples vs. the ATF+4. I will run a temperature ramp from 23C to -40C and see what we get. Stay tuned, I will try to get to it next week.

 

[Jim Allen]

Be very interested to see it.

BUT... is your t-case AWD(center diff) or automatic 4wd? Whetehr or not you mpg will be effected by increased viscosity (and by how much) will boil down to answering that question.

 

[Kestas]

I wouldn't get into a match with the dealer over this. Let them know they put the wrong fluid in there (evidenced by the high viscosity and characteristic smell), and that their answer was unacceptable. That's all you can do. Then move on to making sure the vehicle gets proper maintenance in the future. Dealers need to know their shoddy work is being noticed.

 

[lobo11]

So I have not got a chance to run the viscosity profile on the current gear lube in there, but I did get a chance to run a temperature ramp test from 25C to -50C 2C/min (same shear rate), for Valvoline ATF+4 and Amsoil Universal ATF fluid. The basic differences--from 25C to -46C the viscosities track each other very closely with the ATF+4 being slightly less viscous until -46C where they have the exact same viscosity. After that the Amsoil Universal ATF fluid is less viscous than the ATF+4 fluid. Hope to get the gear Lube checked next week.

 

[martinq]

Originally Posted By: lobo11
The basic differences--from 25C to -46C the viscosities track each other very closely with the ATF+4 being slightly less viscous until -46C where they have the exact same viscosity. After that the Amsoil Universal ATF fluid is less viscous than the ATF+4 fluid.

Just so I understand, from -46C to -50C the Amsoil is less viscous?