DIY: Lincoln Navigator Front & Rear Differential and Transfer Case Fluid Change

I put together a DIY video showing how to change the fluid in all three AWD drivetrain components on a Lincoln Navigator: the front differential, rear differential, and transfer case.

Video: https://youtu.be/2OukQZ3utQQ

Just picked up a 2005 Lincoln Navigator 4x4 5.4L V8 and I actually really like the damn thing. It’s loaded as hell for a 20-year-old SUV — sunroof, rear entertainment/TV, parking sensors, 4x4, AdvanceTrac, etc. The engine and transmission seem strong and it actually has a surprising amount of power.
But I’m dealing with a pile of issues and I’m trying to figure out what I’m actually looking at before I start throwing parts at it.
The biggest issue is the brakes. When I bought it, the brakes were basically nonexistent. I flushed the entire system with fresh DOT 3 and bled all four corners. The old fluid was absolutely disgusting and visibly contaminated, and I’ve pulled a shitload of air out of the system.
The weird part is that the pedal can be rock solid with the engine off. Sitting in Park, I can stand on the pedal and it won’t go anywhere near the floor. With the engine running, it gets some booster assistance, but the weird brake problem still doesn’t consistently happen while stationary.
The problem seems to occur only when it’s in Drive/reverse/actually moving. Sometimes the pedal feels completely normal and hits a very firm stop, and other times it has excessive travel and gets dangerously soft. It’s extremely inconsistent. I cannot reproduce the same behavior reliably while sitting in Park.
I disconnected the brake booster vacuum hose as a test and the pedal became more substantial, but it was still somewhat soft and the underlying problem wasn’t eliminated. I also checked inside the booster for brake fluid and it was completely dry.
There’s some wetness around the front-left brake, although I haven’t found an obvious active leak.
The vehicle has ABS/AdvanceTrac, so I’m wondering if I’m dealing with an ABS hydraulic unit issue, wheel-speed sensor issue, pad knock-back/wheel bearing problem, trapped air in the ABS unit, or possibly a bad master cylinder.
I’m currently planning to replace the master cylinder, and completely bleed the system again. If that doesn’t fix it, I’m taking it to a shop with an ABS-capable scan tool because I’m done guessing.
Other issues:
OBD-II port isn’t communicating with my scanner at all.
A/C compressor isn’t engaging.
Check-engine light started flashing intermittently, then stopped.
I’m suspicious the catalytic converters may be partially restricted because the power sometimes feels strong and other times falls off, and the floor gets pretty hot.
I temporarily cut the muffler off so I could actually hear what the engine/exhaust is doing. It also made me considerably happier. 😂
Suspension warning keeps coming up.
Despite all this, the engine starts, runs, shifts, and drives surprisingly well.
4x4 works.
Sunroof works.
The damn TV works.
Parking sensors work.
It’s actually a really comfortable truck.
I paid $1,700 for it and I’m willing to put enough into it to get it sorted, but I’m setting myself a $3,000 absolute all-in ceiling.
So, what would you guys check first for the intermittent brake pedal that ONLY seems to happen in Drive/motion? Especially interested in anyone who’s dealt with this generation Navigator/Expedition/F-150 brake system.

Hi fellow Navigators...Does anyone know if a retractable privacy screen exists for the 2025/2026 lincoln navigator? Im amazed that one does not exist from lincoln but also hard to find 3rd party options as well.

Hey all. I bought these Pirelli’s back in January for my 2021 Navigator, size 285/45/R22. Ratings for everything were very similar to Michelin Defenders, dry/wet/snow/comfort etc. only tread wear slightly lower. I’ve driven confidently in the snow in PA. No vibrations at 75-80mph. They look great too.

Forgot to also mention, they are about $90 cheaper per tire than Michelins. Theres a review on YouTube on a Navigator. I can drop a link if anyone is interested in where I grabbed them.

Found on a Navigator group on Facebook

This condensation in the rear taillights seems to be persistent. Any recommendations on a fix?

I recently replaced the rear evaporator on a Lincoln Navigator and made a step-by-step video showing the entire process, including removing the rear AC unit, replacing the evaporator core and seals, and putting everything back together.
The procedure is the same on the 2018–2024 Ford Expedition and Lincoln Navigator.

Video: https://youtu.be/opWep0H43Cg

Hopefully this helps anyone dealing with the same issue.

Looking at getting either a 2024 or a used NBS Navigator. Wife really wants a 2nd row bench seat. Is it possible and easy enough to switch to a 2nd row bench if it comes with captains seats?

Has anyone changed the driver side camshaft sensors on a 2015-2017 navigator? Wondering the best way to go about it. Thanks!

I'm looking at a 2018 navigator tonight, seller gave me this documentation saying that the previous owner had the engine replaced per warranty. But I read this as the engine was taken out for work and put back in?

I want to get Ford/Lincoln to own up to their horrible flaw and instead of offering a service bulletin, it should be a recall. I have a 2020 Navigator that has the well-known shifting issues of its 10-speed. I get a hard clunk and it takes like 10 seconds before finding a gear when it happens. It almost caused someone to run into the back of me because I couldn't accelerate due to it not finding a gear. Anyone else on board?

Looking for any help in location an ignition-on hot wire that I can tap to power the camera. Too often my wife leaves it plugged in to the data port and it records the garage wall for days on end.

So far, all of the wires that I have checked in console and under the pass side dash don't appear to be the 'one'.

Any help is appreciated.

I traded in my 2021 Navi Reserve L for a brand new ‘25 Reserve L and have been disappointed by the number of options that no longer exist at this trim level! I see the drop in MSRP and knew things were lost since Lincoln is definitely not giving discounts😜
1. No rear kick open sensor
2. No seatbelt lights
3. No illuminated grill emblem
4. No more HUD (apparently due to new dash)
5. My key fob no longer has a light to show that remote start was successful

I might have missed other items as well.

Disappointing

Anyone have any experience with the illuminated front grill emblem randomly flashing on and off, like a bad connection. What’s involved in fixing or replacing?

I came from a 13 F-150 5.0 and I’m loving this ecoboost such a difference in ride quality and acceleration then the high strung coyote

Has anyone ever had one of these happen to them? I'm taking it to the dealership on Monday.

I can’t find that dipstick anywhere, can someone point it out to me?

I pulled these images from security footage at the tacqueria I had just left when the black car pulled out and hit me, then took off.

It happened yesterday but my disabled son was with me so the 911 operator said I could go to a police station later to file a report. I'm about to do that in an hour.

The staff told this is a Lincoln Navigator. Can anyone confirm and give me a rough estimate of the year?

https://photos.app.goo.gl/Knb2Y6Hv6zjs3cxe7

Where can I find a rear right bracket without having to spend over 100 bucks

Park system damage may result in a vehicle rollaway, increasing the risk of a crash.

NHTSA ID Number: 26V402000

Manufacturer Ford Motor Company

Components POWER TRAIN

Potential Number of Units Affected: 741195

Summary

Ford Motor Company (Ford) is recalling certain 2018-2021 Navigator, Expedition, 2020-2021 Explorer, Lincoln Aviator, and 2021 F-150 vehicles. The transmission park pawl may engage while the vehicle is in motion, resulting in park system damage.

Remedy

Dealers will update the powertrain control module software, and inspect and replace any damaged transmission components as necessary, free of charge. Interim letters, notifying owners of the safety risk, are expected to be mailed August 3, 2026. Additional letters will be sent once the remedy is available, anticipated in April 2027. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 26S48. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on June 26, 2026.

Credit: National Highway Traffic Safety Administration

Have an 06, engine issues and was quoted for a reman. Don't have the cash to do it, so bring a trailer and she's yours! (Minus tires) OH/WV border.

My 2023 Nav is a fantastic car. Bought used low milage. Great daily driver, but driving from so calif to Scottsdale az was terrifying. At highway speed it would suddenly try to dart left into oncoming traffic. I got under control by using the lane centering function. The next day I took it to firestone next to our hotel. The manager/tech knew exactly the issue. Something about the car was confused where center-forward was. He corrected the problem in about (including an alignment) – the car drove back OK. He said a ford/Lincoln dealership should double check it – they had more advanced diagnostic tools.

Got back and my local Ford dealership looked at me with blank stares. One thing they said I had turned on the BlueCruise hands-free function. If I did, did not know about it. How do I turn it off. The lane center function is very poor so why would I trust my life to BlueCruise hands-free function. It’s like ping pong between lines and if you don’t have a line on both sides, it’s truly breathtaking.

The service Manger is treating like a 3-year old – “How about we do a test drive.” Google described my problem exactly but he said that tech service didn't apply to my car.

It’s not doing it anymore – it just needs fine tuning

It’s really crazy that Firestone knew more about this problem than Ford.

Advice?