Change Driveline Fluids Early!

[CarbonSteel]

Thanks everyone for this thread and your contributions.

I used stock viscosities (the Bronco lives at 9000 ft = cooler).

At 25K, front diff fluid was a bit dark, transfer case a bit darker. Rear diff looked great.

Just for awareness (and you may already know this), it is the number to the left of the W that indicates cold weather performance. Ergo, in case you want to step up viscosity from 75W-90 to 75W-110 or 75W-140, they will all perform well in cold weather; e.g 75W-xxx.

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[illverado]

 

[illverado]

Reporting back, 23,500 miles in a little less than a year and my transfer case fluid made me feel like I’m neglecting my first new vehicle :/ Only used 4A ON SNOW AND ICE 1 time for about 50-100 miles to work and back/lunch. Mostly was dead hooked never spun the tires unintentionally. My rear diff didn’t look as bad as OP’s surprisingly but there was a nickel thickness of pookie on the magnet. Front diff next oil change for sure. I have done a lot of serious off-roading in 4L/4H so I wonder if the tc clutches have slipped some or if the fluid was just smoked from going 80mph to work every day

 

[CarbonSteel]

Reporting back, 23,500 miles in a little less than a year and my transfer case fluid made me feel like I’m neglecting my first new vehicle :/ Only used 4A ON SNOW AND ICE 1 time for about 50-100 miles to work and back/lunch. Mostly was dead hooked never spun the tires unintentionally. My rear diff didn’t look as bad as OP’s surprisingly but there was a nickel thickness of pookie on the magnet. Front diff next oil change for sure. I have done a lot of serious off-roading in 4L/4H so I wonder if the tc clutches have slipped some or if the fluid was just smoked from going 80mph to work every day

You have to remember that even in two-wheel drive there are parts inside the transfer case turning that are causing wear metals to be generated.

 

[BadlandsA51]

I'm about to break 12k and one year of ownership so its time for me to cover this.

I have a Badlands with a 7MT, what do I use? It sounds like 75W-110 front and 75W-140 rear, but I want something warranty friendly

I would recommend a good full synthetic. The PTU in our Fusion failed at 42k miles. The oil in it was a semi-solid, black, burnt, smelly mess. I replaced it and filled it with Amsoil 75W-90. I also drilled and tapped a drain hole in the case so the oil could be easily changed. Car has 85k on it now and oil still looks new. These PTUs failed fairly often on these cars, the crappy gear oil was probably the cause of most of the failures.

 

[GroovyGeek]

Today I tried to get a quote from a local stealership for front and rear diff and transfer case fluiid change... they DECLINED. Said that the recommended mileage is 100k and they are not allowed to do it before 60k. Will be calling other dealers, I can't believe they will not take my money.

Yes, I realize that it is a relatively simple process that I can do myself for under $100 but I just don't want to spend half a day on a weekend under the vehicle, particularly with the rear diff not having a drain plug and having to deal with removal of skids. But if they keep refusing to take my money I may do it myself. Definitely not taking it to a quick lube place for some pimply boy to mess with it.

 

[CarbonSteel]

Today I tried to get a quote from a local stealership for front and rear diff and transfer case fluiid change... they DECLINED. Said that the recommended mileage is 100k and they are not allowed to do it before 60k. Will be calling other dealers, I can't believe they will not take my money.

Yes, I realize that it is a relatively simple process that I can do myself for under $100 but I just don't want to spend half a day on a weekend under the vehicle, particularly with the rear diff not having a drain plug and having to deal with removal of skids. But if they keep refusing to take my money I may do it myself. Definitely not taking it to a quick lube place for some pimply boy to mess with it.

Typical dealer bovine scatology. Lifetime fill = what? Until it breaks?

Definitely would change it early and often. Happy to help if I can.

The rear cover has a reusable gasket so it is not difficult from that viewpoint.

 

[GroovyGeek]

https://accessories.ford.com/2021-2023-bronco-m220-hd-rear-axle-differential-cover-m4033br

Use discount code:

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I run one of those code plugins on my browser (from CaptalOne) and it came back with SHOP124 which is 20% off and 2% cashback. Ordering now.

 

[GroovyGeek]

I just finished changing front Dif / Transfer and rear Dif Fluids and installed the Ford Performance cover.. Everyrhing went real well Eze Pze. Used the cheap-po Flo Tool, thanks for that tip! Cut the length of fill tube as needed to get the bottle to Flo without kinking the tube. I used Redline 75w110 and 75w140 and Motorcraft Mercon LV in the transfer case. Reused the factory gasket, very little clean up, being sure to torque the bolts properly. Took a little over 3 hours total. One suggestion, when inside the rear Dif, take your finger and scoop out any fluid in the sump then wipe it out with a shop rag. It's surprising how much fluid is left inside the case.

CarbonSteel, thanks for starting this topic and help throughout.

Be Safe

What was the torque on the rear diff cover? @CarbonSteel 's spreadsheet has a tightening pattern and stage 1 /stage 2 numbers that don't make sense to me.

 

[CarbonSteel]

What was the torque on the rear diff cover? @CarbonSteel 's spreadsheet has a tightening pattern and stage 1 /stage 2 numbers that don't make sense to me.

The first stage is ft-lbs, the second stage is degrees of rotation after tightening to stage one.

22-25ft-lbs will do it.

 

[GroovyGeek]

The first stage is ft-lbs, the second stage is degrees of rotation after tightening to stage one.

22-25ft-lbs will do it.

Thanks for being so helpful. Does everyone stick with Motorcraft MERCON LV Automatic Transmission Fuild? As long as I am ordering from Amsol I figure it would be nice to have everyting from a single vendor

 

[TheKim]

Paid my dealer to do front and rear axles, transfer case, transmission, and oil change. Cost me $600 for all of it, but I'm okay with it. I go through fleet and am chill with the fleet manager, so the guy doing my work is their master tech, and I know it's being done better than I would have.

I did install my own fog lights like a big boy though.
Electrical stuff I'm comfortable with, but fluids and gear boxes get expensive when it gets done wrong.

 

[CarbonSteel]

Thanks for being so helpful. Does everyone stick with Motorcraft MERCON LV Automatic Transmission Fuild? As long as I am ordering from Amsol I figure it would be nice to have everyting from a single vendor

For me, I see no value in running anything other than Mercon LV because it will hold up as well as a premium oil like Amsoil. With that said, Amsoil is top notch lube.

 

[GroovyGeek]

Gang,


- The bolt thread depth in the axle housing is 23mm. If using the OEM rubber and steel gasket with the Ford Performance cover, then you need M8 bolts that are 25mm long. The supplied bolts with the cover are 20mm and they will be too short for the OEM gasket.


Rear Cover Hardware (NEW longer flange bolts are needed if using OEM gasket because it it thicker. They are not needed if using the supplied gasket with the Ford cover--use the supplied bolts that come with the cover):

Flange Bolts: M8x1.25x25mm long - https://belmetric.com/m8-coarse-din-6921-flange-bolt-class-10-9-steel/?sku=BFD8X25YLW

I am trying to buy both the plugs and bolts from McMaster, feels wrong to spend $12 shipping for a $7 order . - TWICE

This seems to be equivalent, 10.9 steel, yellow zinc plated
https://www.mcmaster.com/products/f...h~zinc-yellow-chromate-plated/?s=flange+bolts

Thoughts? Also if we are keeping the plastic brake line clips with the FP cover and reusable gasket I am assuming it is OK to reuse the two original bolt/stud combo and just back off a few ft-lbs on the torque?

 

[CarbonSteel]

I am trying to buy both the plugs and bolts from McMaster, feels wrong to spend $12 shipping for a $7 order . - TWICE

This seems to be equivalent, 10.9 steel, yellow zinc plated
https://www.mcmaster.com/products/f...h~zinc-yellow-chromate-plated/?s=flange+bolts

Thoughts? Also if we are keeping the plastic brake line clips with the FP cover and reusable gasket I am assuming it is OK to reuse the two original bolt/stud combo and just back off a few ft-lbs on the torque?

The bolts posted will work. The OEM studs may be too short because the FP cover is thicker than the OEM and the studs that comes with the FP cover may also be too short because the FP gasket is thinner than the OEM reusable one.

You can buy the studs and bolts from Belmetric though?

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