Mobil 1 Synthetic ATF in Transfer Case

[Oldwolf]

I'm planning to change the Transfer Case fluid in my 2002 Explorer 4x4 and want to put in Mobil 1 ATF fluid. It is Mercon rated which is what Ford recommends for this Transfer Case.

Has anyone already done this? Any problems?

Thanks!

 

[junior426]

Full-time professional dealership mechanic here, my personal truck is a 2002 Explorer XLT 4.6L V8 here. Switched front and rear diffs to Mobil One gear oil and T/C to Mobil One Mercon ATF all at the same time. Probably 20-25k miles since changing the fluids. Absolutely no problems at all. Go ahead and swap it, you will only help things. Just make sure to fill it all they way.

 

[Oldwolf]

What weight M1 did you use in the front differential? As you know Mobil 1 has 75W90 and 75W140 but Ford specifies 80W90. I'm guessing the 75W140 is too heavy for the front.

Only one grade of Mobil 1 ATF is available and it is Ford MERCON, MERCON V, MERCON LV rated so that is what you used most likely.

While I'm at it I am going to replace the rear gear oil in the differential (limited slip) and use the CRC brand friction modifier. Since you are a Ford mechanic you most likely used the Motorcraft XL3 product.

Thanks for your comments.

 

[jrford]

someone once told me, unconfirmed, that it was better to use the 75w140 stuff both front/rear, the only reason to use 75w90 was to save on costs.
"Just make sure to fill it all the way" does that include taking out the rear ABS sensor and adding two pints that way?

 

[my pos mounty]

"Just make sure to fill it all the way" does that include taking out the rear ABS sensor and adding two pints that way?

Your kidding, right?

 

[Carguy3J]

What weight M1 did you use in the front differential? A.)As you know Mobil 1 has 75W90 and 75W140 but Ford specifies 80W90. I'm guessing the 75W140 is too heavy for the front.

Only one grade of Mobil 1 ATF is available and it is Ford MERCON, MERCON V, MERCON LV rated so that is what you used most likely.

B.)While I'm at it I am going to replace the rear gear oil in the differential (limited slip) and use the CRC brand friction modifier. Since you are a Ford mechanic you most likely used the Motorcraft XL3 product.

Thanks for your comments.

A.) Ford specs 75w90 w/o Limited Slip, and 75W140 w/ Limited Slip, if I remember correctly. There was a TSB, updating the oil specs, at least for the 2nd gen. I would just use 75W140 in both front and rear, regardless if LS or not, especially with the rear end gear issues you guys have with the 3rd gens.
B.) As for the "friction modifier". if you use the Mobil 1 75W140 LS, it specifies on the bottle NOT to add addtional friction modifier. Just be aware of that, if you use that. You'll know. It's the stuff that's $18/bottle at Autozone.

 

[Oldwolf]

Mobil told me to add the FM if it is recommended by Ford.

Other threads have indicated w/o using the FM and using LS rated Mobil 1 products the clutch packs will begin to chatter.

 

[xlt03]

All the manufacturers, Redline, Royal Purple, Mobil says you don't have to add FM but my experience is that you will get chatter. Add the modifier. I used the Ford modifier.

 

[junior426]

I would reccomend using the friction modifier regardless of what the bottle says. Also, I reccomend using the 75W90 gear oil for the front diff, but to each his own.

 

[rumpledoll]

I put Mobil 1 Full Synthetic ATF in the transfer case of my 2002 V6 4.0L 4WD Eddie Bauer at ~60,000 miles and I'm now at ~72,000 miles. No issues whatsoever. The original fill for the T-case was plain Mercon rather than Mercon V, so putting in a Mercon V recommended synthetic like the Mobil 1 is a nice upgrade, especially for better low and high temperature use.

At about the same time I changed the front and rear diffs. I changed the rear out twice as the first fill I used Lucas synthetic 75W-140 which had the LS additive in but which still made my rear diff chatter, especially when cold. I switched it out and used Amsoil synthetic Severe Gear 75W-140 in the rear with the additional 4oz of the friction modifier as specified even though Amsoil also had some in the oil. No chatter since doing that final switch.

A note on the rear diff - take out the smaller fill plug first before removing the larger drain plug as the fill plug is harder to remove and there have been several cases on these forums of individuals who removed the drain plug first, and could not get the fill plug out and had to have their truck flatbedded to a shop.

For the front diff I used Valvoline SynPower full synthetic 75W-90 gear oil. The factory fill was non-synthetic 80W-90 oil, but you can always use a lower "W" number as long as the second number is the same - you will just get better cold weather performance. The front diff only has a fill plug so you could either remove the cover, or suck the old fluid out. I sucked the old fluid out - easier and less messy but not quite as good at getting all the old fluid out.

I also changed the transmission fluid by dropping the pan, changing the filter and then using the cooler line to have the engine pump out most of the old fluid while adding new fluid - I used 12 quarts of Schaeffer's ALL-Tran synthetic ATF which has a Mercon V license and is a high quality synthetic fluid.

Rumple

 

[jrford]

Your kidding, right?

believe it or not, not really, i've seen ford documentation which said after you fill it through the fill hole seal it up, remove the ABS sensor and add One more pint?? Its as if the fill hole was spec'd to low or they wanted to raise the fill level to cover the bearings???? When i refilled mine and any other truck i just go to the fill hole. seems odd to me. ..

this post points it out,
http://www.explorerforum.com/forums/showthread.php?t=225982

 

[Oldwolf]

Can I use dino Mercon V in the transfer case even though Ford recommends Mercon only for it?

 

[High_Order1]

Can I use dino Mercon V

wat

 

[Oldwolf]

According to the below I can use Mercon V Syntheic Blend, but not Mercon V Synthetic in my transfer case.


[url]http://www.fcsdchemicalsandlubricants.com/Main/category.asp?select=[Transmission%20Fluid]
[/URL]


MERCON® V Automatic Transmission and Power Steering Fluid

* Motorcraft® MERCON® V is a premium-quality automatic transmission fluid designed, engineered and recommended by Ford Motor Company for use in Ford, Lincoln and Mercury vehicles that require either MERCON® V or MERCON® type fluid. This product also provides excellent performance in electronically controlled automatic transmissions.
* Motorcraft® MERCON® V is manufactured with high-viscosity index, premium-quality, hydroprocessed base oils and specially designed performance additives, which provide excellent shifting characteristics at high and low ambient temperatures, excellent thermal and oxidation resistance and good low temperature fluidity. It provides wear protection and inhibits the formation of gum, sludge, lacquer and foam. It also provides protection against rust and corrosion. It is dyed red for ease of leak detection.
* Do not use in applications where MERCON® SP, MERCON® LV, Continuously Variable Chain Type Transmission Fluid, Motorcraft® Premium Automatic Transmission Fluid, FNR5 Automatic Transmission Fluid or Type F Automatic Transmission Fluid is recommended, or in transfer cases.
* Motorcraft® MERCON® V is suitable for use as a hydraulic oil in a wide variety of industrial applications that call for an ISO 46 or SAE 20W viscosity grade hydraulic oil
* Refer to the Motorcraft® MERCON® V specification sheet at www.motorcraft.com and www.fmcdealer.dealerconnection.com for additional information. For MSDS information call 1-800-448-2063
* Note: MERCON® V Automatic Transmission Fluid is available in bulk quantities at substantial savings. Use of bulk oil products is environmentally proactive. Contact your FCSD Aftermarket Account Manager, an approved Motorcraft® Bulk Oil Distributor, or www.Motorcraft.com for details.





Synthetic Blend MERCON® V Automatic Transmission and Power Steering Fluid

* Motorcraft Synthetic Blend MERCON® V Automatic Transmission and Power Steering Fluid is a high-quality automatic transmission fluid approved and recommended by Ford Motor Company. It was developed for use in the newer electronically controlled automatic transmissions built after 1989 and power steering systems built after 1998 requiring MERCON® V or MERCON® fluid
* Motorcraft Synthetic Blend MERCON® V Automatic Transmission and Power Steering Fluid is formulated with high-viscosity index, premium-quality, synthetic/hydroprocessed base oils and specially designed performance additives. It is specifically formulated to provide improved shifting characteristics at high and low ambient temperatures, excellent thermal and oxidation resistance, and good low temperature fluidity. It provides wear protection and inhibits the formation of gum, sludge, lacquer, and foam. It also provides protection against rust and corrosion
* It is especially effective in applications where high temperatures are a concern. Due to its excellent thermal, oxidative, and shear stability, this fluid is required in manual transmission applications such as Mustang with G1 manual transmissions and F/Eseries with TR 3650 and ZF S5-47 manual transmissions
* Formulated for powersteering systems to provide excellent low temperature fluidity as well as improved high temperature thermal stability for use in extreme conditions in all seasons
* Do not use in applications where MERCON® LV, MERCON® SP, Continously Variable Chain Type Transmission Fluid, Motorcraft® Premium Automatic Transmission Fluid, FNR5 Automatic Transmission Fluid or Type F Automatic Transmission Fluid is recommended.

 

[sportrac03]

Ford has replaced 75w90 with using 75w140 in front and back regardless if you have limited slip or not. If you have limited slip you have to add friction modifier to it (XL-3).

 

[jrford]

Ford has replaced 75w90 with using 75w140 in front and back regardless if you have limited slip or not. If you have limited slip you have to add friction modifier to it (XL-3).

cool, thats what i've been doing, i'm 3.55 open. I thought i read somewhere (TSB? its in my above post but i'm unsure where it came from?) that we are supposed to add another pint through the ABS sensor . . . .is this true?
Thanks Jim

 

[sportrac03]

That part I am not sure of. I can ask a tech if that is true? Which abs sensor are you looking at the one in the dif?

 

[jrford]

please, if you could,
it reads as follows . . .

"NOTE: For roll stability control (RSC) equipped vehicles, remove the rear wheel speed sensor plug. For non-RSC vehicles, remove the rear wheel speed sensor.

Remove the rear wheel speed sensor.
1 Disconnect the rear wheel speed sensor electrical connector.
2 Remove the bolt.
3 Remove the rear wheel speed sensor.
Add one pint of fluid.
Install the ABS sensor and ABS sensor bolt.
Tighten to 27 Nm (20 ft. lbs.) .

found it here . . .
http://www.explorerforum.com/forums/showthread.php?t=225982


Pure speculation on my part . . .
What i think it does is raise the level of the fluid so that the pinion bearing or all bearings for that matter are submerged in oil, less chance of rust build up?

 

[my pos mounty]

Wellllll, it wouldn't be for rust prevention as the lube gets tossed around in the differential by the ring gear, the carrier and spider gears as well as a "slinger" so there is 0 chance of that. Maybe it has something to do with the factory possibly setting up the hole in the differential a little lower than the optimal height?

 

[jrford]

Wellllll, it wouldn't be for rust prevention as the lube gets tossed around in the differential by the ring gear, the carrier and spider gears as well as a "slinger" so there is 0 chance of that. Maybe it has something to do with the factory possibly setting up the hole in the differential a little lower than the optimal height?

i agree in motion everything should be fine, . . .what about sitting for long periods of time, months? One post a year or two ago, someone had pics of the him rebuilding the diff, and from what i remember the rust was on top of the bearing race. . .i've yet to see a definitive Ford documentation on it, like some TSB or service bulletin. . .maybe the hole is too low, if we can only confirm. Could it be the cause the rear diff whine we keep reading about if true?

By the way i filled up to the bottom of the fill hole, . . .trouble sleeping about it now, just kidding LOL.