When to change transmission and rear diff fluid in 2020 f150

[Orangepeel]

My 2020 f-150 came in today. Very pleased with it overall. Ford recommends every 150,000 miles for the trans and rear diff. Would you follow this? The truck has 68k on it. Would you change it now? Maybe wait till 100k? What do you think?

 

[joegreen]

Would change it now. Earlier changes have no downsides except for the monetary hit for the work performed.

 

[Heywood_6078]

Change it after 500 to 1000 miles. Let the gears remove what they will and clean it extremely well and replace fluid.
Just my opinion.

 

[PontiacHO]

My 2020 f-150 came in today. Very pleased with it overall. Ford recommends every 150,000 miles for the trans and rear diff. Would you follow this? The truck has 68k on it. Would you change it now? Maybe wait till 100k? What do you think?

If the trans fluid is still bright red and doesn’t have a scorched odor then it’s probably ok until 100k. The rear differential oil that Ford uses is one of the best you can have. Seen many Ford differential oil changes after more than 70k and the diff oil still had a gold/green color like it was practically new. I’d go 100k on that as well. The exceptions would be if the truck was used for towing and/or hauling. If standard transportation then your good to go.

 

[Jdeere562]

Did my last one at 30,000 miles. right or wrong. Sure won't hurt to do earlier.

 

[SubieRubyRoo]

My 2020 f-150 came in today. Very pleased with it overall. Ford recommends every 150,000 miles for the trans and rear diff. Would you follow this? The truck has 68k on it. Would you change it now? Maybe wait till 100k? What do you think?

I did my rear diff at 76k. I have the E-locker, so there’s no clutch material in there, but my gear oil literally looked new, a transparent yellowish. Filled it back up with HPL 75w110 and a Spicer 9.75 cast iron cover so any future drains don’t require cover removal.

I’ve got 8 gallons of HPL Green CC ATF waiting to go in; I also picked up the PPE deep pan to gain ~1.75qt additional fluid and a magnetic drain pan. I would have done it sooner but time hasn’t permitted. I will try to get it soon; I’m almost at 78k.

In my experience, the rearend is fine but can be changed; if I could go back I’d probably change the ATF between 50-60k. There have been a couple weird flukes with shifting that don’t repeat, but are likely due to old fluid.

Based on testing data, @High Performance Lubricants recommendations, and the fact that both trans and rearend will have additional capacity, I have zero concerns running the HPL somewhere between 75-100k from now.

 

[SubieRubyRoo]

If the trans fluid is still bright red and doesn’t have a scorched odor then it’s probably ok until 100k. The rear differential oil that Ford uses is one of the best you can have. Seen many Ford differential oil changes after more than 70k and the diff oil still had a gold/green color like it was practically new. I’d go 100k on that as well. The exceptions would be if the truck was used for towing and/or hauling. If standard transportation then you’re good to go.

My rear diff fluid looked brand new as well. I was shocked, as all other previous diffs (including my Subarus) looked more black. I have no doubt the OEM fluid could easily be used past 100k if desired.

 

[Furious]

If you want it to last as long as possible service it sooner, every 60,000 miles would be the max I would go on transmissions and do not bs around using maxlife or other multi-vehicle fluids, use officially licensed transmission fluid.

 

[JeffKeryk]

Service that bad boy...

 

[ripcord]

I'd change it. You never know if the previous owner drove it through deep water and got water in the diff.

 

[JTK]

My 2020 f-150 came in today. Very pleased with it overall. Ford recommends every 150,000 miles for the trans and rear diff. Would you follow this? The truck has 68k on it. Would you change it now? Maybe wait till 100k? What do you think?

I too would definitely change those fluids @ 4yrs and ~68K miles. I'd also do the transfer case and front diff if it's 4x4. I'd also oil/wax base rust proof it immediately if it's in the rust belt as well.

 

[barkingspider]

I would replace the fluids asap and use the current miles as a starting point and go from there

 

[Lubener]

My 2020 f-150 came in today. Very pleased with it overall. Ford recommends every 150,000 miles for the trans and rear diff. Would you follow this? The truck has 68k on it. Would you change it now? Maybe wait till 100k? What do you think?

I would change out both now. Then every 40k for transmission and 60k for differential afterward. You could go longer for the differential. Many never change it and never have a problem with it. It's probably the toughest component on the vehicle.

 

[meep]

Yep. the old school numbers have never let me down. First change at 60, then every 30 after that.

pay attention to make sure you get the right fluid type for the trans - probably valvoline ULV. In my 2018, a quarter bottle (very small dose) of “lubeguard red” made the difference between me selling and keeping the truck. If it’s awkward shifting from 3rd to 4th or 5th, go ahead and add it.

I used a mityvac to suck a few quarts out, then 6’ of nylon hose with a funnel stuck in it to fill it from the topside. Also, the dipstick (it’s a little stubby thing) from the 6 speed transmission fits and is useful as a before/after reference point.

you need a 19mm closed wrench to break the fill plug loose. the plug will gouge if you get crooked on it.

 

[Astro14]

I am in the “change it now” camp.

I would add that I prefer a magnetic drain plug in differentials and transfer cases, so, if Ford doesn’t supply one from the factory (like Toyota does) then, I would shop for a new plug before doing the work.

 

[wtd]

I would change it now. When my 2014 Mustang GT had about 3,500 miles on it, I installed an aluminum finned rear diff cover on it. The factory fluid that came out of it looked horrible. Gray in color with a lot of glitter in it. It looked nothing like the new Motorcraft fluid I put back in.

 

[2013ecof150]

using color won’t help when judging the condition of the transmission fluid. Mercon ULV turns black almost immediately. I have been draining and filling mine every 30k

I would service the rear diff, t-case and trans. You can do the front diff if you want. If it’s the original fluid it will probably look milky like it has water in it but it’s really not a concern because Ford uses some kind of marking compound when they set up the gears and it causes the fluid to look like that.

You can use one of those cheap 12v fluid pumps from Amazon to drain and fill the trans. I wouldn’t worry about the filter for now anyway. It’s pretty robust. I’ve seen a few of them cut open after 150k miles or so and there’s really nothing in them.

If you order replacement fill plugs for the rear axle you can swap them into the transfer case and front diff and have magnetic plugs there. Ford only used standard non magnetic plugs there from the factory. They aren’t very expensive either