My 2006 F150 5.4L has 74,000 miles and I've never had the fluid changed. I never tow, rarely haul, but it is tuned (Edge) and I've been running 33's for about 50,000 miles. It has recently started downshifting hard from 4-3 with the converter locked.

I've read so much on this issue that I honestly don't know what to do, so I really need some advice. Should I:

1) Drop the pan and change the fluid
2) Drop the pan, change the fluid and filter
3) Passive flush - no chemicals

Thanks in advance.

 

Passive flush, no chemicals. However, it may be tune-related.

 

I should have mentioned that the tune hasn't changed in quite a while. Shifting has been smooth until recently. Leaning towards the passive flush -thx.

 

A tune can get corrupted - I'm suggesting you return it to stock for troubleshooting purposes.

 

I dropped the pan & changed the fluid and filter every 30K on all my past police cars (radar, pursuits, long idling, long high speed responses, etc) ....
.... and I aim to do the same at no later than 50K mile (or earlier) intervals on my personal vehicles which see much easier use.

I also have a good aux cooler in addition to that which is OEM on each of my automatic equipped cars and my '77 F150.

My '07 FX4 has a large OEM cooler (maybe part of tow package?) and oem tires, SC light tow 87 tune, 3.55s, & seldom tows ....
.... and trans temps according to SGII pretty much always stay under 170 ....
.... usually hovering about 155-160.

So I'ld vote:

2) Drop the pan, change the fluid and filter

 

I can't find anyone do do a passive exchange and I'm not going to do a flush, with or without chemicals, so it looks like dropping the pan and replacing the filter is going to be the ticket. 5 quarts is better than nothing and I can always do it again in 10,000 miles or so. I might even use a pump and siphon it at that point. No point in dropping it again since the filter will be new.

 

Most shops have a machine that will actually do a passive exchange. It connects to the cooler lines, you fill the reservoir with fluid, and run the engine. The tranny pump does the work, pumping the old fluid out and drawing the new fluid in. They probably call it a "flush" but it really isn't.

You can do an exchange yourself:

http://www.ford-trucks.com/articles/...-transmission/

I know it says E4OD/4R100 but principle is the same for your 4R75.

 

I explained exactly that process to two dealers and three transmission shops and no one could make it happen. Thanks for the link. Like I said, after my filter is changed, I shouldn't have to drop the pan again for quite a while.

 

The quick oil change joints should have that machine, when I had an automatic that's exactly how it was used.

 

There's a write-up somewhere on here about flushing your transmission 4 quarts at a time. I did that and what it does is flush your TC which is where your problem may lie. It cured my problems and improved shifting dramatically. I'll repeat mine every 25K.

 

Jaws, check my link. That's the RIGHT way to do it yourself.