2017 F150 engine oil and diff fluid?

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Apr 3, 2021
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I have a new to me 2017 F150 4x4 5.0 with 33k miles on it and decided to change the diff fluids and oil since I don’t know the history of the vehicle prior to me owning it. I didn’t remove the cover, just vacuumed out the diffs and refilled. Ford recommends 75w85 fluid for the front and rear however I went with Mobil 1 75w90 for the front and Mobil 1 75w140 for the back. Does anyone else use these weights and are they appropriate? I chose 75w140 for the rear because they 2015 models were originally spec’d to 75w140 and assuming the differentials are the same I’d rather prioritize wear protection over MPG. For the front, 75w90 was readily available and I rarely use 4WD. I also used Mobil 1 synthetic 5w30 oil to try to protect the engine better and reduce some of the noise however I am considering going back to 5w20 just for warranty sake. I’d like to keep the truck for 10 years so I’m curious to see what everyone’s preference is with engine oil and diff fluid on 2015-2020 F150s.
 
I have a 2015 2 wheel drive F150 and put 75W-140 in the diffs. The 2018 F350 gets 75W-90 in the front and 75W-140 in the rear diffs. I would use 5W-30 especially is you run the engine hard. though the 20 seemsm to work for them ownership of most peoples vehicles.
 
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I have a 15 F150 5.0. I am running 5-30 in my engine. I moved from Mobil 1 0-20 to SuperTech 5-30 synthetic and a 6k OCI with a Fram Ultra filter doing 2 OCI's.

I bought the truck new and at 25k IIRC dumped the front and rear diff fluid. I used Mobil 1 75-90 front and Mobil 1 75-140 rear. I sleep well with that combo.
 
Good choices all. I would not be concerned about warranty, because as long as you change the oil it will appear fine - they are not going to send it out for analysis.
 
Thanks for the replies everyone, sounds like the fluids I chose are about on par with what you all are using. I love the 5.0/6 speed drivetrain so hopefully with these fluids I’ll get many more years of trouble free ownership.
 
@Jmcgrady1994 - your choices for axle oil are fine. For decades, Ford specc'ed 75W-140 for its rear truck axles. If you use 4x4 a great deal you may want to consider moving the front axle viscosity up to 75W-110 or even 75W-140 to increase the protection.
 
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Thanks for the replies everyone, sounds like the fluids I chose are about on par with what you all are using. I love the 5.0/6 speed drivetrain so hopefully with these fluids I’ll get many more years of trouble free ownership.

I have to agree. I have found the 6R80 and the 5.0 to be an excellent combination. Quite smooth and responsive in sport mode.
 
I run the same fluid in my diffs.

The 5.0L is not picky. I've run everything from Harvest King 5W20 to PP 10W30. Right now it has a 5W20 frankenbrew with 6qt's of Havoline HMSB 5W20 and Harvest King 5W20.
 
I run the same fluid in my diffs.

The 5.0L is not picky. I've run everything from Harvest King 5W20 to PP 10W30. Right now it has a 5W20 frankenbrew with 6qt's of Havoline HMSB 5W20 and Harvest King 5W20.
That gives me some piece of mind. I’ve heard people claim that the VVT operates off of oil pressure and a change in oil weight can cause issues but apparently the 5.0 in mustangs recommend heavier weight oils for track use so I can’t imagine much damage would occur. I went to 5w30 mostly to see if there was a reduction in noise but honestly I don’t notice much difference compared to 5w20.
 
That gives me some piece of mind. I’ve heard people claim that the VVT operates off of oil pressure and a change in oil weight can cause issues but apparently the 5.0 in mustangs recommend heavier weight oils for track use so I can’t imagine much damage would occur. I went to 5w30 mostly to see if there was a reduction in noise but honestly I don’t notice much difference compared to 5w20.

I actually ran Amsoil 0w-40 in my 2013....it was very quiet and smooth, no loss of power or mpg that I could detect.
 
That gives me some piece of mind. I’ve heard people claim that the VVT operates off of oil pressure and a change in oil weight can cause issues but apparently the 5.0 in mustangs recommend heavier weight oils for track use so I can’t imagine much damage would occur. I went to 5w30 mostly to see if there was a reduction in noise but honestly I don’t notice much difference compared to 5w20.
Motor oil grades fall into a specific viscosity range. A 5W20 with a viscosity higher in it's range could be close to a 5W30 that is lower in it's range, or if the 5W30 sheers a bit in use, it could drop into the higher 20 grade range. Temperature plays into the oil's viscosity as well, so your 2 gallon oil sump is likely not heating up to the KV100 value of the oil if you're only bopping around town (especially in winter).
Swapping to 5W30 is not going to cause any VVT issues.
I recommend reading some of the articles on the main BITOG site page.
 
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Dont overthink it.

Motorcraft $5 or Fram Ultra $11 oil filters commonly available at Walmart.

Any brand name oil. I'm partial to Valvoline Synthetic and Castrol Magnatec simply because I got about 100 quarts of them for 75cents each.

When its cold run 0w20 or 5w20. When its hot run 0w30, 5w30 or mix up viscosities with whatever 20w and 30w you have on hand. The engine wont care.

I'd run the gear oil your truck is spec'd for. You aren't hauling a 30k pound horse trailer every day. Mine spec's synthetic 90w. I have some 140w left over from my Excursion I could have used but I didnt see the point. I'll take the small mpg boost of 90w syrup over unneeded "extra" protection of 140w pudding.

You should consider ATF drain and fills every year. Maybe also replace most of the brake fluid in the reservoir every 2 years. Both are simple to do and are cheap insurance.
 
That gives me some piece of mind. I’ve heard people claim that the VVT operates off of oil pressure and a change in oil weight can cause issues but apparently the 5.0 in mustangs recommend heavier weight oils for track use so I can’t imagine much damage would occur. I went to 5w30 mostly to see if there was a reduction in noise but honestly I don’t notice much difference compared to 5w20.
Try Castrol Edge for noise reduction
 
I put 75w140 in my 2016 rear differential. ford's 9.75" axle had that spec for 20 years before 2015. Then all of a sudden 75w90 with no changes. Edge 0w40 in my 2009 5.4 and the same in my 2016 eco. Both ran/run great with it.
 
Dont overthink it.

Motorcraft $5 or Fram Ultra $11 oil filters commonly available at Walmart.

Any brand name oil. I'm partial to Valvoline Synthetic and Castrol Magnatec simply because I got about 100 quarts of them for 75cents each.

When its cold run 0w20 or 5w20. When its hot run 0w30, 5w30 or mix up viscosities with whatever 20w and 30w you have on hand. The engine wont care.

I'd run the gear oil your truck is spec'd for. You aren't hauling a 30k pound horse trailer every day. Mine spec's synthetic 90w. I have some 140w left over from my Excursion I could have used but I didnt see the point. I'll take the small mpg boost of 90w syrup over unneeded "extra" protection of 140w pudding.

You should consider ATF drain and fills every year. Maybe also replace most of the brake fluid in the reservoir every 2 years. Both are simple to do and are cheap insurance.
If 75w140 won’t hurt anything but a slight mpg decrease then I think I’d prefer to keep using it as I’ve noticed the the clunk I experience when accelerating after coasting is greatly reduced with the thicker diff fluid. It very well may be placebo but I’ll consider going back to 75w90 when I remove the diff cover at 60k miles. My next project is doing a drain and fill for the ATF fluid but I’m trying to find a trans pan that has a drain plug so I can do drain and fills easier. ATF fluid is cheap enough for me to want to do a drain and fills every 30k miles. Also looking for a diff cover for the super 8.8 diff that has a drain plug.
 
If 75w140 won’t hurt anything but a slight mpg decrease then I think I’d prefer to keep using it as I’ve noticed the the clunk I experience when accelerating after coasting is greatly reduced with the thicker diff fluid. It very well may be placebo but I’ll consider going back to 75w90 when I remove the diff cover at 60k miles. My next project is doing a drain and fill for the ATF fluid but I’m trying to find a trans pan that has a drain plug so I can do drain and fills easier. ATF fluid is cheap enough for me to want to do a drain and fills every 30k miles. Also looking for a diff cover for the super 8.8 diff that has a drain plug.
Been there, done that. Here's my takeaway:

Dorman makes a stock style, stamped pan with a drain plug in the bottom. I worried the tack welded fitting might come loose or leak. Its about $30 at Advance Auto Parts with an online code.

A few boutique brands have thick cast aluminum pans with greater capacity and drain plugs. Reviews are more mixed than I care for on what's really just an overbuilt cookie sheet. They are usually $300+.

I've drain and filled my F150 3x over last 40k in an effort to gradually refresh the most of the fluid in my 145k mile truck. Never had any trans related issues, just a maintenance thing for me.

After dropping the pan the first time (to inspect and clean) it was obvious, in my case, that
dropping the pan more than once every few years would be superfluous. Nothing to see there.

This is what I've settled on and maybe it will give you somewhere to start. I use a $12 syphon pump with fairly tough rubber hoses, a foot of 1/4-3/8 ID aluminum or copper tubing and 6" of plastic tubing. The copper tubing get bent to your preference, connects the rubber syphon hose to the plastic tubing and protects the contraption from the heat of the catalytic convertors. The plastic tubing goes about 5-6" into the dip stick/plug. Pump ATF out into a quarts or liters graduated bucket so you have some idea how much new fluid to put back in. Swap hoses/ends on syphon pump and put same amount of fresh fluid back in. Check fluid level according to manufacturer recommendations. Add/remove as necessary using the pump.

The rear gear covers are sexy. I had one on the Excursion. Actually, it came with it when I bought it from previous owner. Way easier to service than regular dif covers. I only used it once in 100k miles. If I could score one on eBay cheap enough I'd get another but I don't see them being worth the retail cost. You can buy A LOT of RTV for $100. Lol.
 
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Been there, done that. Here's my takeaway:

Dorman makes a stock style, stamped pan with a drain plug in the bottom. I worried the tack welded fitting might come loose or leak. Its about $30 at Advance Auto Parts with an online code.

A few boutique brands have thick cast aluminum pans with greater capacity and drain plugs. Reviews are more mixed than I care for on what's really just an overbuilt cookie sheet. They are usually $300+.

I've drain and filled my F150 3x over last 40k in an effort to gradually refresh the most of the fluid in my 145k mile truck. Never had any trans related issues, just a maintenance thing for me.

After dropping the pan the first time (to inspect and clean) it was obvious, in my case, that
dropping the pan more than once every few years would be superfluous. Nothing to see there.

This is what I've settled on and maybe it will give you somewhere to start. I use a $12 syphon pump with fairly tough rubber hoses, a foot of 1/4-3/8 ID aluminum or copper tubing and 6" of plastic tubing. The copper tubing get bent to your preference, connects the rubber syphon hose to the plastic tubing and protects the contraption from the heat of the catalytic convertors. The plastic tubing goes about 5-6" into the dip stick/plug. Pump ATF out into a quarts or liters graduated bucket so you have some idea how much new fluid to put back in. Swap hoses/ends on syphon pump and put same amount of fresh fluid back in. Check fluid level according to manufacturer recommendations. Add/remove as necessary using the pump.

The rear gear covers are sexy. I had one on the Excursion. Actually, it came with it when I bought it from previous owner. Way easier to service than regular dif covers. I only used it once in 100k miles. If I could score one on eBay cheap enough I'd get another but I don't see them being worth the retail cost. You can buy A LOT of RTV for $100. Lol.
Thanks for the tip on pumping out the ATF to replenish. I definitely think I will take that approach as I’m not thrilled by the reviews I’ve seen on aftermarket pans. I’m tempted to drop the pan now and replace the filter and continue to replenish the ATF via pump every 15k miles or so but I’ve seen people insist that the filter is robust enough to go much longer without being replaced. You’re right about the diff cover though, they seem to run around 200-300 for an aftermarket one and I can just as easily pump out the fluid and pump in new fluid if I’m not going to remove the cover every time.

I’m sure replenishing these fluids at this frequency is way more than whats needed but I love this truck and want to own it well outside of the warranty period. Hoping a couple hundred dollars now will save me thousands of dollars in the future.
 
Thanks for the tip on pumping out the ATF to replenish. I definitely think I will take that approach as I’m not thrilled by the reviews I’ve seen on aftermarket pans. I’m tempted to drop the pan now and replace the filter and continue to replenish the ATF via pump every 15k miles or so but I’ve seen people insist that the filter is robust enough to go much longer without being replaced. You’re right about the diff cover though, they seem to run around 200-300 for an aftermarket one and I can just as easily pump out the fluid and pump in new fluid if I’m not going to remove the cover every time.

I’m sure replenishing these fluids at this frequency is way more than whats needed but I love this truck and want to own it well outside of the warranty period. Hoping a couple hundred dollars now will save me thousands of dollars in the future.
Its "lifetime" ATF. Yeah right...

Drain and fills using a pump is the way to go. Way cleaner and far less chance for something to go wrong like cross threading the tiny pan bolts or develop leaks than dropping pan all the time. Still, as easy as it is, you'll reach a point of diminishing returns and after the third or fourth short interval you can probably treat it as an annual affair. Burning your knuckles on hot exhaust gets less and less fun anyway.

Make sure you clean that side of the transmission and the floor pan very thoroughly. Be particularly discriminant around the area immediately proximal to the dipstick and the 19-21mm bolt/cover fitting. You don't want dirt or crud getting in there.

I changed the filter the first time. It looked alright but figured while I was in there, might as well. I didn't have any debris in my pan and only a tiny amount of powder on the magnets. I don't think I'll do it again for at least another 100k miles. Its a good sized filter with a felt style element.

If you decide to do the filter remember the factory gasket is a reusable, well engineered part. Its metal with rubber oring treatments at important spots. Just go over the pan flange lightly with a brass wire brush and then clean all the mating surfaces with brake cleaner and lintless/microfiber rags before bolting the pan back up. Make sure the old oring comes out with the old filter. Be careful not to score the aluminum bore when fishing it out if it doesn't. Lastly, the new filter likes to be cute and play games. It will dangle down gradually and then drop out just as you are getting the pan lined up. Its a pain in the butt. You have to make sure its positioned properly and then hustle to get the pan in place pretty quickly.

Hope this helps and good luck!
 
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