Gen 2 Raptor Transfer Case Fluid Change (2017–2020)

Who this is for

This covers the transfer case on the Gen 2 Raptor, 2017 through 2020. Worth knowing up front that the fluid in here is automatic transmission fluid, not gear oil — Ford specs Motorcraft MERCON LV for this case, the same fluid family you'd associate with the transmission rather than the thick 75W-85 hypoid lube the differentials take. Owners who service all three in one weekend sometimes assume the transfer case gets whatever the axles got, and it doesn't. The fluid itself — Motorcraft MERCON LV — doesn't change across the generation, but the fill amount does: Ford's 2017 supplement calls for 1.5 quarts and the 2019 supplement calls for 1.9 quarts for the exact same transfer case fluid. That's the single most important thing to get right here — don't carry one year's number over to another without checking. If you drive a 2018 or 2020, we don't have a verified figure for your specific year; fill to the level your own supplement specifies rather than splitting the difference between 2017 and 2019. The transfer case is what actually shifts the Raptor between 2WD, 4-Auto, 4-High and 4-Low, so a low or degraded fill here shows up as rougher shifts between modes rather than a dramatic failure — it's an easy service to put off precisely because it doesn't announce itself loudly when it's overdue.

Steps

1. 1

   Confirm your model year's fill figure before you start

   This is the step that actually matters most on this job: Ford's 2017 Raptor supplement lists 1.5 quarts (1.4 L) for the transfer case, while the 2019 supplement lists 1.9 quarts (1.8 L) for the same fluid. Know which figure applies to your truck before you buy fluid or start draining, rather than assuming one number covers the whole generation.

2. 2

   Position the truck and locate the fill and drain points

   Jack the truck on rated stands if you need the extra room, and locate both the transfer case's drain and fill points before removing anything. Position your drain pan underneath.

3. 3

   Pull the fill plug first

   Loosen the fill plug before you touch the drain — if it's seized, better to know with the fluid still in the case than after it's already drained out.

4. 4

   Drain the old fluid

   Remove the drain plug and let the old MERCON LV fluid drain completely into the pan. While it's draining, take a look at the fluid's color and check for any metal particles, which would be worth investigating further before refilling.

5. 5

   Reinstall the drain plug

   Thread the drain plug back in by hand first, then snug it with a ratchet, torquing to the spec in your service manual.

6. 6

   Refill to your model year's specified level

   Using a pump or squeeze bottle through the fill hole, add Motorcraft MERCON LV to the level your service manual specifies for your truck's model year — 1.5 qt for a verified 2017, 1.9 qt for a verified 2019, and whatever your own supplement calls for if you're driving a 2018 or 2020. If your truck is a Gen 3 instead, Ford's 2022 manual lists 1.9 qt for that generation's transfer case, for reference.

7. 7

   Reinstall the fill plug and check for leaks

   Torque the fill plug to spec, lower the truck, and take it for a short drive. Recheck both plugs for seepage once it's back up on stands.

8. 8

   Dispose of the old fluid

   Pour the drained fluid into a sealed container and take it to a recycling center that accepts transmission and transfer case fluid.

9. 9

   Cycle through the drive modes once you're back on the road

   After the refill, take the truck through 2WD, 4-Auto, 4-High and 4-Low on a short drive, if conditions allow it safely, to confirm each mode engages smoothly. A fresh fill with the correct fluid and level should shift noticeably cleaner than a transfer case that's gone a long time between services. Note that 4-Low generally wants the truck stopped or nearly so to engage, so pick somewhere you can do that safely rather than trying it at speed.

10. 10

    Note it in your records with the year-specific figure

    Write down the date and the amount you actually put in, not just "transfer case serviced." The whole reason this job has a trap in it is that the quantity depends on the model year, and the next person under this truck — a future you, or a buyer's mechanic — benefits from knowing which figure was used rather than having to work it out from scratch. If you service the front and rear differentials in the same session, log those separately; they take a different fluid entirely and the records getting merged is how the wrong lube ends up in something later.

Specs

Safety notes

• Never get under a truck supported only by a jack — use rated stands.
• Don't trust one year's capacity figure for the whole generation; this fluid's fill amount actually changes between the 2017 and 2019 supplements.
• If you drive a 2018 or 2020, confirm the fill level in your own supplement rather than splitting the difference.
• Take the old fluid to a recycling center; never pour it down a drain.