2019 F-150 when to change gear oil

2

2013ecof150

Joined
Sep 10, 2018
Messages
233
Location
Northern va
My 2013 F-150 was totaled after hitting a deer, so I bought a new 2019 F-150.

I was looking underneath it today getting acquainted where everything is and I pulled the rear diff plug and couldn't touch any oil with my finger at all. Bent a small piece of wire and could touch oil about one inch below the fill hole. I thought it was supposed to be just blow the fill hole?

Same thing for the transfer case. About one inch below the check and fill hole.

How long should I wait to change the oil for break in purposes? I tow car trailers a couple of times a year but most of the time I'm riding unloaded.

I know it specs 75w85. Any reason to use anything thicker? I was thinking to use the 75w110 Amsoil and forget about it for 75,000 miles. But I'm not opposed to using the 75w85.

Does a transfer case shed metal during break in? I suppose I'd use the recommended mercon LV.
 
I changed the differential at 20k miles to get rid of the break in metals. I used ford's 75w140 that has been Ford spec in their axles for eons up to 2015. Nothing in the differential changed, but the spec changed to 75w90 or 75w85 or something in 2015...probably to meet EPA fleet fuel economy requirements.

Changed my transfer case to redline D4 around the same time.
 
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I did my front diff, rear diff, trans case, and trans pan drop with filter change at =about 25k on my 15 F150. I used Mobil 1 75/90 in the diff's and will change again at 100k. Never a bad thing to get the break in metals outa the locker.
 
20-25k seems like a good mileage to drain everything then!

I have some 75w90 laying around. I still think I'll top off the rear and pickup a quart of LV and top off the transfer case as well. Seems like an inch ( or more ) below the fill hole is too low.
 
OP, I come from the same school of thought as you concerning differential/transfer case levels when checked. I'd had questioning attitude also if level was 1" below fill hole. But what if that was correct level? When you drain them next time add exactly as stated in owners/service manual and then see if there both still 1" low. I use Redline 75W-85 GL-5 in both my differentials as stated by manufacture. Little more expensive then off the shelf 75W-90 gear oil. Ford F150 are best looking trucks IMO.
 
Most axle wear occurs at 15K or less and despite longer and longer OCIs after that, the wear metals will always be less per mile (unless there is a mechanical issue). I would change it no later than 15K and I would install 75W-140 in it as that is the oil that Ford specified for decades in those axles before the CAFE gremlin reared its head.

I have had substantial service from Amsoil severe gear and if you elect not to go with 75W-140, I would absolutely use 75W-110 as it is the upper viscosity that 75W-90 used to be before the SAE J306 tables were updated some time ago.
 
The owners manual should tell you what the oils levels should be. Most (older) Fords are like around 1/4 inch below the fill plug hole. I fill mine until it's about to spill out.
 
I always have filled it until it came running out the fill hole and then called it off and called it good.

I'm kinda torn on what weight to use. Half of me wants to stick with the super light weight 75w85. And use " what it calls for "

On the other hand I have drums of Delvac 80w140 synthetic at work that I could put in it and it wouldn't cost me a dime.

I always thought that a thicker oil on a diff would protect better.

Then I wonder if the engineers at Ford would really put such a lightweight oil in their differentials to get .01 more mpg and it actually wear out the rear faster. Especially since it's " lifetime fill"

I have about a years worth of mileage to put on the truck before I think about changing it anyway
 
I own a 2018 F250 with a 6.2L motor
I changed my rear diff at 25K and replaced the gear oil with
Mobil 1 75/140
Smooth as silk and mpg hasn't changed at all.
 
Went outside and checked the oil levels in the rear and transfer case again after sitting all night.

Took 19 ounces of 75w90 to top off the rear till a small stream of oil came out of the fill hole

Took exactly 16 ounces of mercon LV in the transfer case to be level with the fill hole.

I didn't see anything in the manual saying how close to the fill hole the level should be, only the quantity
 
The old school method of fill until it runs out is no longer accurate. The GM manuals all show a fill about an inch below the plug level, I suspect Ford is similar these days. Over filling the diff accomplishes nothing.https://my.chevrolet.com/content/dam/gmownercenter/gmna/dynamic/manuals/2018/Chevrolet/Silverado/2018-chevrolet-silverado-owners-manual.pdf Page 365
 
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Originally Posted by 64bawagon
The old school method of fill until it runs out is no longer accurate. The GM manuals all show a fill about an inch below the plug level, I suspect Ford is similar these days. Over filling the diff accomplishes nothing


How can it not at least let things run slightly cooler with more mass of fluid to dissipate heat? Whats the purpose of making the fill plug higher than it needs to be just the physical location you can put it at? I will continue to fill till it drips, easy way to not make a mistake and check it one a year also.
 
Originally Posted by 2013ecof150
My 2013 F-150 was totaled after hitting a deer, so I bought a new 2019 F-150.

I was looking underneath it today getting acquainted where everything is and I pulled the rear diff plug and couldn't touch any oil with my finger at all. Bent a small piece of wire and could touch oil about one inch below the fill hole. I thought it was supposed to be just blow the fill hole?

Same thing for the transfer case. About one inch below the check and fill hole.

How long should I wait to change the oil for break in purposes? I tow car trailers a couple of times a year but most of the time I'm riding unloaded.

I know it specs 75w85. Any reason to use anything thicker? I was thinking to use the 75w110 Amsoil and forget about it for 75,000 miles. But I'm not opposed to using the 75w85.

Does a transfer case shed metal during break in? I suppose I'd use the recommended mercon LV.



I changed mine in my 2007 at 180,000 and put Mercon LV back in it. No glitter look to the oil or shavings on the plug. Probably would have lasted forever.
 
How can it not at least let things run slightly cooler with more mass of fluid to dissipate heat? Whats the purpose of making the fill plug higher than it needs to be just the physical location you can put it at? I will continue to fill till it drips, easy way to not make a mistake and check it one a year also. [/quote]

I totally agree with this.
 
Originally Posted by mpgo4th
Originally Posted by 2013ecof150
My 2013 F-150 was totaled after hitting a deer, so I bought a new 2019 F-150.

I was looking underneath it today getting acquainted where everything is and I pulled the rear diff plug and couldn't touch any oil with my finger at all. Bent a small piece of wire and could touch oil about one inch below the fill hole. I thought it was supposed to be just blow the fill hole?

Same thing for the transfer case. About one inch below the check and fill hole.

How long should I wait to change the oil for break in purposes? I tow car trailers a couple of times a year but most of the time I'm riding unloaded.

I know it specs 75w85. Any reason to use anything thicker? I was thinking to use the 75w110 Amsoil and forget about it for 75,000 miles. But I'm not opposed to using the 75w85.

Does a transfer case shed metal during break in? I suppose I'd use the recommended mercon LV.



I changed mine in my 2007 at 180,000 and put Mercon LV back in it. No glitter look to the oil or shavings on the plug. Probably would have lasted forever.


This was the first fluid change on my 2017 3500HD Duramax transfer case at just a few miles shy of 16,000 miles. I'm gonna go about another 10k and dump it again.

[Linked Image]
 
Originally Posted by BlakeB
Originally Posted by mpgo4th
Originally Posted by 2013ecof150
My 2013 F-150 was totaled after hitting a deer, so I bought a new 2019 F-150.

I was looking underneath it today getting acquainted where everything is and I pulled the rear diff plug and couldn't touch any oil with my finger at all. Bent a small piece of wire and could touch oil about one inch below the fill hole. I thought it was supposed to be just blow the fill hole?

Same thing for the transfer case. About one inch below the check and fill hole.

How long should I wait to change the oil for break in purposes? I tow car trailers a couple of times a year but most of the time I'm riding unloaded.

I know it specs 75w85. Any reason to use anything thicker? I was thinking to use the 75w110 Amsoil and forget about it for 75,000 miles. But I'm not opposed to using the 75w85.

Does a transfer case shed metal during break in? I suppose I'd use the recommended mercon LV.



I changed mine in my 2007 at 180,000 and put Mercon LV back in it. No glitter look to the oil or shavings on the plug. Probably would have lasted forever.


This was the first fluid change on my 2017 3500HD Duramax transfer case at just a few miles shy of 16,000 miles. I'm gonna go about another 10k and dump it again.

[Linked Image]



Man that's a hairy plug !!
And just think more rear diffs never get changed
 
Wow that's a lot after only 16000 miles! I never saw anything like that on my 2013 truck that was totaled, but I changed that every 30k with the XL-12 fluid.
 
I just recently changed mine for the first time in my f150. 32 years old and 99k miles. Don't believe in regular diff oil and power steering oil changes. Way over emphasized.
If you have that much shavings as previously shown in 16k miles, you got issues going on in that punkin that is not normal.
 
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