my truck- 2003 F350 ext cab 6.0 turbo diesel, auto, 3.73 gears, leveling kit, 35" tires, 4" exhaust

the truck has almost 39,000 miles. the transmission fluid is pretty clean looking, and has always been at the right level without having to add much, if any. i do alot of towing, and mostly highway miles.

im debating if i should change the tranny fluid. ive known a ton of people who had no tranny problems until they changed the fluid / filter... 2 weeks later the tranny is fried.

so how often do you change yours ?? ever had problems afterwards? im pretty sure the manual says to change it at 30,000 miles... oops...

 

Never- I have a T-18 4 speed manual.

Sorry, I had to throw that one in.

See what your manual says don't forget to use the correct type of ATF for your vehicle. I guess it also depends on how you drive and if/what you tow.

When I did have an A.T., changed it every couple of years and never had a problem. But that's me.

Good luck

 

I'm pretty sure those who claim that the change of tranny fluid caused their tranny to go south had never changed it in the first place. So the tranny was going to fail pretty soon anyway. I changed mine at 30k, as the manual states because I'm still under warranty and want to keep it that way, just in case

 

Check with these guys down here.

 

well being that you tow it is a must you change it at 30,000 the fluid loses its ability to protect the parts and will wear out the tranny and by not changing it you void the warranty trust me if you have a warranty on it and it goes they will pull a fluid sample and find out how old that fluid is and will ask for proof of service if you can't provide you buy the new 4,000.00 tranny

 

just change it, don't have it flushed. That seems to cause more problems than it fixes.

 

Don't just change the fluid, you won't get as much changed. Use this method:

https://www.ford-trucks.com/article/...nsmission.html

 

If you do it at ~30k intervals, I don't think you really have to worry about getting every drop out. If it was me, I'd just drop the pan, check the filter and replace if needed, and refill.

 

I have flushed mine at ~25K intervals (3 times), have 77K on it now. I tow quite a bit so I change it more often

 

To check the filter you need to cut it open. So checking is out, just replace it.

Changing the fluid in the pan and not changing the fluid in the converter is a waste of time and money. You will change less than half of the total this way. The article I posted above will change about 90%-95% of the fluid. It also has an option to change the filter. The author said that he changes the filter every other change.

 

Umm - the filter is basically a screen. No need to cut it open, it's easy to see if there's gunk in it.

I guess we'll have to disagree on the merits of changing all of the oil at such low intervals. I think the risk of damage to the transmission by running the engine with lines disconnected is not worth the benefit of removing more of the fluid. If you want to drain more of the ATF it's easier (and safer) to just remove the torque converter plug (if possible).

I just drop the pan and change what comes out. Never had a problem.

 

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Oppy, I'm from the same school as you. Well said, and I agree. It might not remove as much total ATF, but there is less chance of blocking a trans line with sediment, etc. The best way, which I have done, is to install a drain plug in the pan. This way, you can remove more ATF, more often. For example, you can simply empty the pan, once every year,whether it needs changed or not, and replace with fresh ATF, full of additives etc. Then, about every 4th year, pull the pan, and do a complete change with a new filter (screen). With the trans drain, it makes the process easy, as the pan is light and empty of any ATF. Also, many transmission shops will drill and install a permenant drain bolt, for around $20, including the cost of the drain bolt + labor.

 

Somebody agrees with me?? That's a first!

Well said Ed - couldn't agree with you more!

 

Once every 100k or so, or when it looks 'bad', whichever comes first.

Though I'm planning on switching to a 50k schedule and installing an auxiliary filter, knowing that E4OD's are a tad expensive.

 

My methodology is to change it when it starts to change color or smell. Or when the manual says to change it, whichever comes first. Plus, always use exactly what the manual says to use.

If there's a torque converter drain, always do that too. Also, just change the filter when you're in there. Just like engine oil change, you always change the filter.