Gear Oil Recommendations - Ford Flex

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abs

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Need some help with gear oil recommendations for my AWD EcoBoost Ford Flex.

The factory fill rear differential fluid is a dino 80w-90 Motorcraft XY-80W90-QL conforming to the following specs: MIL-PRF-2105E, Mack GO-J, WSP-M2C197-A, GL-5 and MT-1 specs.

I also need a replacement fluid for the PTU (power transfer unit or transfer case). The factory fill PTU fluid is synthetic 75w-140 Motorcraft XY-75W140-QL conforming to the following specs: WSL-M2C192-A, GL-5.

What would be better options (if any) to replace the factory fill? I think I'd like to go with synthetic oils in both units.

Also want to stick with the OEM spec'd 80w-90 weight in the rear differential (will not consider a 75w-90) since the cold viscosity is so much lower (from 7.0 cSt to 4.1 cSt minimum) when going down from an 80 to a 75.

Lastly, I will not consider any "boutique" oils which are not certified to meet a certain spec while claiming that it meets or exceeds the performance of the spec. I am personally not comfortable with using oils which are not certified. I believe this requirement will eliminate the likes of Amsoil and Redline for example.

Thanks in advance.
 
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Originally Posted By: abs


The factory fill rear differential fluid is a dino 80w-90 Motorcraft XY-80W90-QL conforming to the following specs: MIL-PRF-2105E, Mack GO-J, WSP-M2C197-A, GL-5 and MT-1 specs.




U know when I read that, remind me of valvoline 80w90 , that is exactly how it say on back of that valvoline bottle.

If you have to go with 80w90 , then go with valvoline durablend 80w90 ( just 1 dollar more then white bottle ) add ford addictive lsd bottle

if u have to go with synthetic, then go with redline 75w140 or Mobil 1 75w140 add ford addictive lsd bottle
 
Originally Posted By: dparm
Not finding much that meets M2C197-A. Is that a very new spec?


The material defined by this specification is a solvent refined petroleum base lubricant blended with thermally stable sulfur/ phosphorus/nitrogen/boron extreme pressure additives. The oil has improved thermal and oxidation stability and functions at SAE J2360 / MIL –PRF-2105E performance level.
 
Originally Posted By: abs


Also want to stick with the OEM spec'd 80w-90 weight in the rear differential (will not consider a 75w-90) since the cold viscosity is so much lower (from 7.0 cSt to 4.1 cSt minimum) when going down from an 80 to a 75.

L


What are those numbers for? They certainly are not cold numbers for Gear Lube,

Amsoil 75W90
Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 16.9
Kinematic Viscosity @ 40°C, cst (ASTM D-445) 114.7

If you insist on 80W90 you might consider Chevron ESI 80W90 (500,000 mile rated). Its a Hydrocracked Base instead of PAO and you will likely have to go to a Volvo Truck dealer to get it. It was designed as a more affordable alternative to PAO based synthetics required for 500,000 mile drains on truck axles.
 
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Originally Posted By: abs
Need some help with gear oil recommendations for my AWD EcoBoost Ford Flex.

The factory fill rear differential fluid is a dino 80w-90 Motorcraft XY-80W90-QL conforming to the following specs: MIL-PRF-2105E, Mack GO-J, WSP-M2C197-A, GL-5 and MT-1 specs.

I also need a replacement fluid for the PTU (power transfer unit or transfer case). The factory fill PTU fluid is synthetic 75w-140 Motorcraft XY-75W140-QL conforming to the following specs: WSL-M2C192-A, GL-5.

What would be better options (if any) to replace the factory fill? I think I'd like to go with synthetic oils in both units.

Also want to stick with the OEM spec'd 80w-90 weight in the rear differential (will not consider a 75w-90) since the cold viscosity is so much lower (from 7.0 cSt to 4.1 cSt minimum) when going down from an 80 to a 75.

Lastly, I will not consider any "boutique" oils which are not certified to meet a certain spec while claiming that it meets or exceeds the performance of the spec. I am personally not comfortable with using oils which are not certified. I believe this requirement will eliminate the likes of Amsoil and Redline for example.

Thanks in advance.


If you're absolutely set on using a gear lube which is officially certified to meet Ford's specific spec (WSP-M2C197-A), then I'm pretty sure that you're going to be limited to the factory-specified lubricants. Of course, you'll also be limited to Ford's brake fluid to meet that obsure spec, etc.

I could be missing something really obvious, and it certainly wouldn't be the first time, but what would be the problem with running a 75W90 versus 80W90? Why would you want the cold viscosity to be higher, all else equal? I figure that's the benefit of running a higher-quality fluid?

FWIW, I'm using Mobil1 Synthetic LS 75W90 in my Freestyle, both in the front PTU and the rear differential--though the FS uses a Volvo PTU and rear end, it calls for the same spec in the owner's manual. In the factory service manual however, it says "or meets GL-5"... I've had it in for about 25K and so far so good.

I researched this to death when I changed my fluids, and I was very comfortable using fluids which didn't have the official Ford certification. After removing the factory fill, I thought I should have spent more time changing fluid and less time researching which one! They didn't look great, particularly for "lifetime fluids". My first choice was Amsoil's Severe Gear, followed by M175W90--which just ended up being easier to get.
 
abs, with all the arbitrary restrictions you've put on the choices, why not just use the factory-recommended fluids? They're easily available at any dealer.
 
Quote:
What are those numbers for? They certainly are not cold numbers for Gear Lube,


I believe those cSt values equate to a MONOGRADE SAE 75W gear oil, not for any MULTIGRADE 75W90 gear oil which we all know will be in the mid-teens to low-20's at 100C. SAE 75W is allowed to be this "thin" at 100C, which is way too impractical for modern use.

Quote:
I could be missing something really obvious, and it certainly wouldn't be the first time, but what would be the problem with running a 75W90 versus 80W90? Why would you want the cold viscosity to be higher, all else equal? I figure that's the benefit of running a higher-quality fluid?


I concur, flow is life. Why do you want to run a more viscous fluid at low temperatures? A 75W90 will be less viscous than a 80W90 when cold, and at operating temp both will be exactly the same.
 
I do not understand why anyone would want to run 80W-90 over a 75W-90, there is no advantage. Besides, most of the synthetic 75W-90s get by with little or no VIIs so shear or fluid longevity isn't even an advantage for a 80W-90.
 
Folks - I really appreciate all the quick feedback on this one. My sincere apology, I made an error in my original post with respect to the viscosity values. Those numbers are at 100 degrees celcius and I got the values from here:

http://www.lubrizol.com/DrivelineAdditives/AutomotiveGearOil/J306Specifications.html

I "think" the reason I want to stick with the OEM 80-90 instead of a 75-90 is to make sure that the cold viscosity is not too thin . . . I am figuring that Ford could easily have spec'd a 75-90 and there must be a good reason not for doing so but I'm also not an expert and could easily be wrong. Hence my asking for everyone's input
grin.gif


I do concur that the Ford specification on that fluid is somewhat esoteric, I have yet to find another gear oil certified to that spec.

Having said that, I have found the following products all of which seem to be pretty good, especially some of the Schaeffer's products and the Chevron Delo ESI seems to have a bit of a following:

Schaeffer 293 Gear Lube
Schaeffer 293a No Tack Gear Lube
Schaeffer 267 Gear Lube
Mobil Mobilube HD Plus
Motul Gearbox
Castrol Hypoy C
Chevron Delo ESI (also mentioned above)
Havoline Gear Oil
Valvoline Durablend

Each of these are available in the 80w-90 weight and minimally conform to the GL-5 spec. Many also are MT-1. Some are either Mack G0-J or Mack G0-J+. Most are also MIL-PRF-2105E and some meet one or more Ford specs, but not the one on the OEM stuff in my vehicle. Very interested in reactions and feedback on these. One issue with the Schaeffer's products is I'm not sure how to get these in small volumes (less than a 5 gallon pail).

My goals are to a) reduce wear and tear on the differential and b) to possibly improve fuel economy by reducing friction.

I certainly would consider the OEM fill if we conclude that is the best choice even though not synthetic.
 
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Originally Posted By: JOD
FWIW, I'm using Mobil1 Synthetic LS 75W90 in my Freestyle, both in the front PTU and the rear differential--though the FS uses a Volvo PTU and rear end, it calls for the same spec in the owner's manual. In the factory service manual however, it says "or meets GL-5"... I've had it in for about 25K and so far so good.

I researched this to death when I changed my fluids, and I was very comfortable using fluids which didn't have the official Ford certification. After removing the factory fill, I thought I should have spent more time changing fluid and less time researching which one! They didn't look great, particularly for "lifetime fluids". My first choice was Amsoil's Severe Gear, followed by M175W90--which just ended up being easier to get.


If you don't mind my asking, how many miles on your Freestyle when you did finally change the differential and the PTU oils? Can you share more about the condition of the oils at that mileage?
 
Originally Posted By: abs
I "think" the reason I want to stick with the OEM 80-90 instead of a 75-90 is to make sure that the cold viscosity is not too thin . . . I am figuring that Ford could easily have spec'd a 75-90 and there must be a good reason not for doing so but I'm also not an expert and could easily be wrong. Hence my asking for everyone's input
grin.gif



Not a chance, gear oils in either 75W-90 or 80W-90 get extremely thick when cold, and are certainly MUCH, MUCH, MUCH thicker than they are when hot. Since the Ford diff can tolerate a heated up 80W-90, the cold flow properties of 75W-90 will only be a benefit.

Ford calls for a 80W-90 because they determined that a synthetic 75W-90 wasn't "necessary" for the application and thus can save a few bucks at the assembly plant.
 
Originally Posted By: abs

If you don't mind my asking, how many miles on your Freestyle when you did finally change the differential and the PTU oils? Can you share more about the condition of the oils at that mileage?


Here's a pic of the PTU fluid here.

Obviously, color's not the best determinant, but it also seemed to have thickened up a little. It wasn't horrible, but it wasn't great, either. I didn't do a UOA on it. The rear differential fluid was a different story. It's a dino-based fluid, and it was in much worse condition, thick, gritty, and generally in bad shape. These were changed at 90K.

I ended up running the rear diff fluid for 10K and changed it again. It was almost clear. I'll probably go 40K on that from now one. On the front PTU, I had a tough time getting out all of the fluid, so I did a few evac/fill until it was clear, and now I'm going to do a single evac/fill once a year/20K. I've decided to stick with Mobil1 Synthetic 75W90. I'm at 105K now and going strong.

I'm going to do the haldex fluid once a year and the filter every other, but you don't have that to mess with on the Flex.
 
Originally Posted By: Ben99GT


Ford calls for a 80W-90 because they determined that a synthetic 75W-90 wasn't "necessary" for the application and thus can save a few bucks at the assembly plant.



Yep, those are my thoughts exactly. I actually think the rear diff on this car leads an easy life, but just for the sake of simplicity it makes sense to use a synthetic 75W90 GL-5 fluid for the rear. You need it for the front anyway, so if just seems more simple to use the same fluid front and rear. It seems to be a cost-saving measure on Ford's part not to use a synthetic fluid for the rear.
 
I've been continuing my research and, based on the feedback, I am considering a 75w-90 grade oils too. So, looking across a range of 75w-90 and 80w-90 gear oils, it looks like the values at operating temps vary quite a bit within both grades.

Also realizing now that if at 100C (around 212F) the viscosity is in the 15cSt range, then at 40C (around 100F) or below, a lower viscosity should be preferable for better cold flow (as you all already pointed out to me). So now my question is should I be trying to target a high quality syn with a 40C viscosity as low as possible? I will still be considering other variables like VI, wear tests, foam test, oxidation tests, certifications, etc.

From the list below which oils does everyone recommend keeping in mind the certifications on the OEM gear oil (first post)?

Here are some examples revealing the sometimes very significant differences in viscosity (cSt) at both 40C and 100C. Lists are grouped by stated weights with averages and high/low listed:

............................40C............100C
Amsoil 80w-90...............116............14.9
Brad Penn 80w-90............140............14.5
Castrol HypoyC 80w-90.......N/A............14.1
Delo ESI 80w-90.............140............14.2
Fuchs BOA 80w-90............152.03.........15.03
Havoline 80w-90.............145............14.2
Mobil HDPlus 80w-90.........139............14.5
Motul Gear 80w-90...........127............16.3
Schaeffer's 293 80w-90*.....180-251........17.5-23.0
Valvoline Durablend 80w-90..136............14.8

Averages:...................145............15.28
Lowest:.....................116............14.1
Highest:....................215.5..........20.25 (both Schaeffer's)

*Note: Averages used for Schaeffer's ranges


............................40C............100C
Amsoil SG 75w-90............114.7..........16.9
Brad Penn Syn 75w-90........122............16.6
Castrol HypoyC 75w-90*......N/A............15.0-17.5
Castrol Syntec 75w-90.......N/A............15.0
Conklin Gold Guard 75w-90...83.2..........14.2
Delvac 75w-90...............120...........15.9
Fuchs Silktran Syn5 75w-90..125...........16.9
Mobil1 Syn LS 75w-90.........99...........15.2
Motul Gear 75w-90............81...........14.5
Pennzoil GL5 75w-90.........110...........15.7
Redline 75w-90..............115...........16.4
Schaeffer's 293 75w-90*.....90-115........13.5-16.0

Averages:...................107.2.........15.69
Lowest:......................81...........14.2
Highest:....................125...........16.9

*Note: Averages used for Schaeffer's & Castrol ranges


............................40C............100C
Amsoil 75w-110..............146.6..........20.3
Motul 300...................105............14.2





 
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Okay, so with more searching, I've discovered that the only 80w-90 gear lube meeting the Ford WSP-M2C197-A specs as well as all the other listed specs is a Conoco-Philips product called "Universal Gear Lubricant". I "think" this product is the OEM fill rebranded under the Motorcraft name or is very, very close to it. Also, as a side note, it is my understanding that many of the Motorcraft lubes are manufactured by Conoco-Philips (like the Motorcraft engine oils). Anyway, this gear lubricant has a cSt viscosity at 40C of 146 and at 100C of 14.5.

I can clearly see that this fluid has substantially higher viscosity at cooler temps than almost any 75w-90 weight gear oil. Can anyone help me understand why Ford would not have just spec'd a 75w-90 dino fluid to begin with? Was it because they were concerned that the dino fluid would shear down over time so spec'd a higher starting viscosity? Was it because they wanted a better quality lubricant with fewer VI improvers? Just trying to make sure I'm not missing something before I pull the trigger on my next gear oil.
 
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Originally Posted By: abs
Okay, so with more searching, I've discovered that the only 80w-90 gear lube meeting the Ford WSP-M2C197-A specs as well as all the other listed specs is a Conoco-Philips product called "Universal Gear Lubricant". I "think" this product is the OEM fill rebranded under the Motorcraft name or is very, very close to it. Also, as a side note, it is my understanding that many of the Motorcraft lubes are manufactured by Conoco-Philips (like the Motorcraft engine oils). Anyway, this gear lubricant has a cSt viscosity at 40C of 146 and at 100C of 14.5.

I can clearly see that this fluid has substantially higher viscosity at cooler temps than almost any 75w-90 weight gear oil. Can anyone help me understand why Ford would not have just spec'd a 75w-90 dino fluid to begin with? Was it because they were concerned that the dino fluid would shear down over time so spec'd a higher starting viscosity? Was it because they wanted a better quality lubricant with fewer VI improvers? Just trying to make sure I'm not missing something before I pull the trigger on my next gear oil.


Cost is the only reason. The PTU sees a much tougher life, and it uses 75W90, so that should answer that question for you. I'd definitely go 75W90 in the rear, and just use whatever fluid you decide on for both F/R applications.
 
Hi JOD, thanks for the response. Guess I will go for the 75w-90 for the rear, most likely the Delvac. For the PTU, I still have to make a choice, that unit requires the 75w-140.
 
I'm reviving this thread because Ford appears to be having some issues with its synthetic 75w-140 gear oil (described earlier in the thread)when used in the PTUs. Apparently a significant percentage of these PTUs are failing, at least in part due to the oil severely thickening to the point that it looks like grease. Here are links to photos of what I'm talking about from two different Ford vehicles, both equipped with a Ford PTU, both failed and both had the Motorcraft 75w-140 lube in them:

Ford Edge Failed PTU

Taurus X Failed PTU

As previously discussed, Ford considers their 75W-140 Motorcraft lube to be a lifetime fluid. Based on these photos it would seem the truth may be far different.

I personally replaced the PTU fluid in my Ford Flex Ecoboost last weekend at 60k miles and discovered that the fluid was very black but also notably thicker than the brand new Motorcraft 75W-140 fluid in the bottle. It had not reached the point where I was unable to suction it out of the PTU (there is no drain plug) but there is no question that it had begun to thicken.

So the questions are many:

1) What could cause a 75W-140 Synthetic gear lube to thicken up like this? Ford has had some issues with the PTU air vent clogging on some vehicles - could that affect this situation? Does gear lube thicken due to overheating, due to water/moisture accumulation in the oil, due to running out of additive pack, or for other reasons?

2) What fluids, if any, would be more likely to withstand the tough conditions in these PTUs and help folks like me avoid a failure? Obviously more frequent changes (or any fluid changes) should be mandatory and I wouldn't be surprised to see Ford issue a TSB on that eventually. In the meantime, what are some great oil options?

As previously noted, I prefer products that are fully tested to meet industry accepted specs. As an example, I am about to switch my rear differential to Mobil Delvac 75w-90 which has a very long list of approvals . . . What is available with a similar list of approvals in the 70W-140 viscosity?

Regards,

Andrew
 
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I'm not very knowledgeable about this stuff. I have a 2008 Ford Escape XLT. Can I use Mobil 1 75W/90 instead of Motorcraft SAE 80W/-90? I live on the east coast and cold weather is fast approaching.
 
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