Several questions so please bear with me.

My mom has a 1996 Explorer XLT 4x4. Has about 160k miles and I just took it for an oil change. Differentials and transfer case need attention, supposedly, but she never uses the 4-wheel drive aspect of the car, so I'm not worried about that (it is appropriate to not worry about it, right?)

Brake fluid was low so I bought some. My concern is the transmission fluid. He said it was pretty dirty and it was black. I don't know when it was changed last, if ever. The car seems to drive fine and she hardly drives. She's put on like 30-40k miles in the last decade. I do want to get it changed out but only if you guys think it should be done at this point. I heard on some videos that changing out the transmission fluid on cars with this kind of mileage can be problematic. Should I proceed to get it done?

I wanted to get it done at a Jiffy Lube. Do they use the right fluid?

Alternatively, I could do it myself to save a few bucks. I saw a nice video on YouTube on how to remove the pan, filter, and gasket so I think I could comfortably do it. Again, only if you guys think it's a good idea at this point to drain and fill. I wouldn't consider a flush because I heard that's really bad and should only be used on cars that the transmission is on its last leg.

I want to take care of her car. They don't make them like this anymore which is a shame. I'd appreciate any other tips you guys may have.

 

Which engine does her Explorer have? This makes a pretty big difference on which transmission it will have. The 4 speed with overdrive in the V8 is probably easier to change at home by the average DIY'er than the 5 speed mated to the V6. The 5-speed requires a somewhat unique setup to properly fill it. Since supposedly the shop checked the fluid and it was black, that would suggest she has the V8 with the 4-speed transmission since it has a dipstick. If her Explorer is the V6 then I'd find a different shop since there's not an easy way (no dipstick) to check the level or condition of the transmission fluid. Either way, if the fluid is worn out and black and/or stinky, I'd suggest a drain and refill with a new filter. This will be a messy process on the 4-speed. It's actually less likely to get messy on the 5 speed because of the drain plug.

Regarding the differentials and transfer case, the rear differential and the transfer case are spinning any time the vehicle is moving. The front differential doesn't see as much load if she's not using the 4WD often, but really all 3 should be serviced if you're really concerned with keeping he vehicle maintained.

If the brake fluid was low enough that it needed to be topped off either there is a fluid leak somewhere or the brake pads are worn enough that they should be checked. You should check them over for leaks and pad wear. Be prepared that if you pull the rear rotors off you'll likely discover that the parking brake shoes have separated from the shoe bases.

-Rod

 

As the saying goes, “use it or lose it”. I’ve seen plenty of 4WD setups just stop working if never exercised. T-case motors get dirtied up as well.

As for flushes, they get a bad rep because folks wait until the transmission is basically toast before trying one out. I’ve never had a problem with one, because I don’t wait for funny shifting or dark fluid to happen first. I think it’s called “preventative maintenance.”

I wouldn't even bother with a drain and fill. All you do at that point is dilute a few quarts of fresh fluid with the 3/4s of the trans fluid that’s still in the torque converter. Start fresh.

 

For exactly the reasons you point out, the flush may not be the first course of action to take here. If the fluid is already trashed, flushing and starting fresh may remove too much trash and cause the transmission clutches to engage from what I've read. But also keep in mind, this is from what I've read, not from first hand experience. I invite the original poster (OP) to do his/her own research. The theory behind this seems to be that if there is a lot of clutch friction material in the old fluid, and the transmission adapts clutch pressures to accommodate this, removing the majority of the fluid and replacing it with fresh, non-contaminated fluid, may be too slippery for the clutches to "grab" and cause the transmission to have excessive slip, especially if the learned clutch volume indexes (I'm not sure if Ford also uses that term) are not reset.

In this case, if the OP does opt to have a flush performed, I'd recommend making sure the transmission filter will also be replaced.

-Rod