Nuke

Drive it as usual and just do the recommended maintenance, although the Ford recommended frequencies are overly conservative. If done right, tranny fluid changeswon't hurt anything. But too many shops don't perform the proper method.

My previous 5 Toyota's were all high mileage (150k - 250k miles) and I changed fluids typically at 2-3 times less frequent than Toyota's recommended frequencies. My current Toyota has almost 100k miles and I just replaced the drive train fluids for the 1st time and I tow regularly. And I don't figure on doing it again until 200k miles.

Just use common sense.

allenmaty

I always make sure to change the trans filter every 25K miles (easy number to remember) It's cheap insurance and I have never had a trans fail me. 220K miles on my 15 year old Crown Vic and my wifes 27 year old Firebird both still running on the original trans.

LordRipberger

What about the fluid?

allenmaty

I replace the fluid lost due to the filter change, about 3-4 quarts, but don't worry about the rest in the torque convert until 100K (10 quarts). ATF oil doesn't really go bad unless it's been overheated, the most important part to change is the filter. If any pressure drop develops across there it means less pressure to operate the clutches and internals which will wear the parts sooner.

LordRipberger

So I finally got around to looking up the scheduled maintenance. It says that the automatic transmission fluid doesn't need to be changed until 150,000 miles (unless you are having issues). So that settles that.

Other things to do...
- change PCV valve
- change spark plugs
- replace engine coolant
- Check belts, hoses, break lines, etc. (this isn't until 105k, but I figure I would do it at 100K since I will be doing so much already.)

I do have a question. The schedule has cars equipped with a transaxle replacing the fluid every 30K miles. Why is the transaxle fluid so sensitive (or heavily used) compared to the automatic transmission that only needs its fluid changed once in 150k?

Acronym questions:
And what are cars equipped with CVT?
What options are ford cars with 4F50N and 4F27E?

Thanks.

jz78817

don't worry about it; Mustangs don't have a transaxle.

a continuously variable transmission. basically a transmission with no fixed gear ratios. as far as modern Ford vehicles are concerned, only the hybrids have CVTs.

the 4F50N is the new name for the old AXOD/AX4S transaxle which isn't used in anything anymore. The 4F27E is used in like one car which isn't sold in North America so don't worry about it.

LordRipberger

I realized the mustang didn't have a transaxle, I was asking because I curious.

A continuously variable transmission? That sounds pretty cool. I will need to learn more about this.

ThaiCobra

make sure with the sparkplugs that you go to a Ford dealer who will replace all spark plugs AND cover additional work that needs to be done if a sparkplug breaks.

I only had 60k on mine, and I had 2 sparkplugs break during the replacement process. It's very likely plugs will break on yours at 100k, when they go to take them out. If you take it in with someone who charges for the additional labor you could be out like $300 - $600.

Don't make the same mistake I did.

And fluids and belts like everyone else said for replacement.

JFitz

As someone who just replaced his transmission, I can definitively say DO NOT change your auto trans fluid after 100k. This will only make any problems worse or make new problems present themselves. My trans was clunking into reverse after hesitation and the shifts felt...just not right. So, they pulled the pan and found brass shavings in one part of the pan and more shavings on the magnet. At that point I was already doing new fluid so I told them to go ahead, knowing that I was in for a new transmission in the future anyway. It IMMEDIATELY felt worse.

The fresh fluid is harsher than the original. The new detergent flushes all the dirt out of the torque converter and the little nooks and corners and cycles it through all the gears. When I took it to my trans guy, I could see that the 5th gear planet was chewed up, the Sprague wasn't locking properly and the converter wasn't locking because it wasn't getting enough pressure, making it feel like the trans was slipping off the line.

The fluid change made a future problem something I had to take care of now.

I would not recommend changing the trans fluid. Older autos were made to change the fluid. More modern vehicles (post 80's) don't seem to be designed to be maintained, just replaced. I won't be buying any more automatic vehicles for my fun cars.

allenmaty

And that is exactly why changing the trans filter every 25K will prevent these issues. The auto transmissions are one of the most overlooked maintenance items. But it needs to be kept up from the beginning, once the wear sets in it's just a matter of time before it goes, whether you change the fluid or not.

I suggest getting a shift kit, helps the strength and longevity of the transmission, also much more fun to drive .