Do I need to get the transfer case fluid and transmission fluid changed?

I drive a 4×4 Expedition, and last time I went in for an oil change, the mechanic said I should get my transfer case fluid and transmission fluid changed out. I've been up to date on all other maintenance, but I've never done that. I've heard conflicting reports on whether changing the transmission fluid is necessary, and I've never heard of changing out the transfer case fluid. Are either of those things necessary?

My car has 70000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi, thanks for writing in. I looked at your maintenance schedule for your vehicle and found that for up to 150,000 miles, it only says to inspect the fluid level and not change it. The fluids are special fluids and if you did need any work done (i.e. if there is a leak present or other mechanical problem) then make sure the correct Ford certified fluid is used.

When it is time for you to have your transmission fluid serviced, consider having a certified automotive technician from YourMechanic come to your home or office to perform the service for you.

Hope this helps and best of luck!

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Most mechanics recommend that you replace the transfer case fluid once every 50,000 km. However, the average life of the transfer case fluid depends on how your vehicle is used. If you regularly tow large loads or put other forms of stress on your transfer case, the fluid should be inspected regularly.
Most transfer cases are filled with an automatic transmission fluid, which is usually red in colour. Others use a thicker gear oil, and some use a specialized fluid that is specifically made just for that transfer case.
The transfer case is always working, whether you use the four wheel drive on your vehicle or not. Your transfer case fluid level should be checked every time that you get an oil change.
You should have your differential and transfer case fluid checked every 30,000 miles, or when you experience any of the symptoms below. Changing these fluids is a messy job, but your local Brakes Plus team is here to help – we never mind getting our hands dirty!
If you drive manual, most manufacturers will recommend changing your transmission fluid every 30,000 to 60,000 miles. If you have automatic, you can typically boost that range up to 60,000 to 100,000 miles. There`s no harm in changing your fluid early.
Commonly, a transfer case will fail due to a low fluid level caused by leaks, a lack of maintenance or regular wear and tear. It`s important to address fluid leaks right away to prevent internal transfer case damage. Changing the transfer case fluid on a regular basis is also important.
If you are wondering can bad transfer case damage transmission, the answer is yes, sometimes. Both are part of the drivetrain, and in the case of a serious transfer case failure damage to the transmission and other parts of the vehicle may occur.
Usually the gaskets between the transmission and the transfer case are known as the transfer case gasket or the transfer case adapter gasket. The gasket may be listed as the type of transfer case and then followed by the words adapter and gasket.
Over time transfer case fluid becomes contaminated due to carbon build up from cooling hot drivetrain components. This may affect a vehicle`s performance, causing the vehicle to shudder when turning or emit whining sounds. If the fluid runs low or becomes contaminated, it can lead to failure of the differential.
The transfer case disengages when you`re in two-wheel drive mode and is no longer necessary. This can be done by simply flipping a switch on the dashboard or floor of your vehicle, depending on the make and model.
Over time transfer case fluid becomes contaminated due to carbon build up from cooling hot drivetrain components. This may affect a vehicle`s performance, causing the vehicle to shudder when turning or emit whining sounds. If the fluid runs low or becomes contaminated, it can lead to failure of the differential.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Do I need to get the transfer case fluid and transmission fluid changed?
ANSWER : Hi, thanks for writing in. I looked at your maintenance schedule for your vehicle and found that for up to 150,000 miles, it only says to inspect the fluid level and not change it. The fluids are special fluids and if you did need any work done (i.e. if there is a leak present or other mechanical problem) then make sure the correct Ford certified fluid is used.

When it is time for you to have your transmission fluid serviced, consider having a certified automotive technician from YourMechanic come to your home or office to perform the service for you.

Hope this helps and best of luck!

Problem with transfer case
ANSWER : The two vehicles had different types of transfer case assemblies depending on if it has part time and automatic full time type systems. The differences between the two transfer cases may be more than just the shift motor swap. If you took the transfer case out of a part time suburban vehicle and tried to put it in a full time automatic type system, it may get damaged when driving. Also the internal gearing could be different between the two vehicles but that would be hard to tell. You can take a chance and try it or get the correct one for your vehicle.

There is automatic transmission fluid in a manual transmission. Is it okay to leave or do I need manual transmission fluid?
ANSWER : This would depend on what the manufacturer recommends. Many manual transmissions do take automatic transmission fluid. If your transmission has ATF in it, it is very likely that it is supposed to have that in there. If not, it is likely that the transmission would not function properly with the wrong fluid. Many manual transmissions will also take engine oil as a lubricant. The best way to know for sure is to check your owner’s manual or call your local General Motors dealership to inquire.

Does my transmission fluid need to be changed?
ANSWER : The color of used transmission fluid is not particularly relevant in judging the remaining life of the fluid. If the fluid is visibly contaminated with particulate matter and/or the fluid has a burnt odor, as a consequence of overheating, those would be relevant inspection factors. Fluid with a burnt odor, for example, should be changed at once. There is no recommendation in your Ford manual to change the automatic transmission at any particular interval, assuming the vehicle is used in normal service. However, Ford does clearly state that if the Escape is used for trailer towing the fluid should be changed every 30,000 miles, that is frequently. As a compromise, even though Ford does NOT require it, it is definitely a good maintenance practice to change the fluid at least every 100,000 miles in normal service. As far as the mechanic’s remark that changing the fluid would cause problems, in YOUR circumstances, that is with a relatively new vehicle that has only moderate miles, that advice is technically incorrect and unwise. If you are curious, ask the mechanic to cite specific literature, journal articles, field test data, lab results or other actual, tangible, documentable evidence that there is potential harm. If he supplies such evidence, take it into consideration. If he supplies nothing, you can safely ignore the "advice" that he gave you. If you desire, YourMechanic does perform transmission fluid exchanges on a mobile basis. The service to request would be transmission fluid/filter change. If you have any further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Does this transmission have a transmission filter that can or needs to be change at certain miles?
ANSWER : Most vehicles have an internal transmission filter that can be changed by removing the transmission pan. Some diesel trucks will have an external filter that can be changed just like an oil filter. The transmission filter is usually recommended to be replaced either when the transmission fluid is replaced or around 100,000 miles depending on the manufacturer’s recommendation.

As for which fluid to use, I would recommend looking in you owners manual. Your owners manual will list all fluid specifications that are required for your vehicle including capacity and type. I would always recommend using what the manufacturer recommends for the vehicle.

If you’d like to have your transmission fluid and filter serviced, consider YourMechanic, as one of our mobile technicians can come to your home or office to do so.

New cars don’t have transmission fluid dipsticks Transmission fluid changing
ANSWER : That’s a very good question. The reason they have gone with no dipsticks is because they don’t want people messing with transmissions other there at the dealership. Some cars went through that a couple of decades ago. They make it a very involved, convoluted process all through, in order to change the fluid on these modern cars. They have special adapters you have to put. Some of them have to have scan computers in order to read the data and what’s in there, and then be able to change it. A lot of these companies claim that this new fluid is the "lifetime" fluid.

Most new use synthetic fluid can last a long time but any fluid is going to get dirty and wear out over time. I would change it at least every 80,000 – 100,000 miles but if you’ve got one that is really hard to change, you are better off hiring a mechanic to do it.

On some of the cars, it would be too hard for the do-it-yourself because of all that equipment you need. The professional mechanics already have that. Just call any good mechanic, like one from YourMechanic, and they will be able to perform a transmission fluid service for you.

is it safe to change Transmission Fluid. Hasn’t been changed in a long time. Currently the Transmission is working fine; no slip
ANSWER : I agree with the other mechanic. If the fluid looks dirty then this means the transmission was not serviced for a long time and if you service it then the new fluid will wash out all the clutch material that is being held together by the old fluid. You would be taking a big chance that the transmission will start slipping within a week after you service it.

A 75-point safety inspection is a good idea after long-term storage, and a qualified technician from YourMechanic can perform this for you at your home or office.

I went to get an oil change, and the mechanic noticed a leak in my transmission. This was on Saturday. They put more fluid in it.
ANSWER : There could be a leak on the input shaft, output shaft, oil pan, dipstick grommet, or the seal on the shifter linkage could be leaking. I recommend seeking out a professional, such as one from Your Mechanic, to help you diagnose the leak on your transmission.