I have a 2003 F150 4.6 with 84,000 miles. Runs fine, but should I change the original trans fluid? Appreciate any responses.

 

probably a good idea.

Best is to drop the pan and change the filter, but this only gets 4-5 of 14 qts changed, so a 2nd or 3rd change of fluid helps get most all the old fluid out.
I installed a drain plug on my pan so I could drain it easier (I have 168,000 miles on mine with the first change being done a few hundred miles ago).

Also, Autozone has Maxlife ATF on sale for $11/gallon, so a good deal.

 

If it was mine I would....BUT....When I did mine I got 2 new filters and extra tranny fluid...1st I dropped the pan and put in a new filter...buttoned things back up... refilled with tranny fluid...drove a bit til things were up to temp....then back to change the filter again & refill again.

Yes that is a bit extreme, one reason was that I did not own the truck until it was much farther down the road, so to speak, then what your truck has and the former owner couldn't recall doing it. reason 2 was The debate was not favorable to "flushing" the tranny fluid via a outside flushing machine. Part of the contention was that a flushing machine would break loose more contaminates and lodge them valve body, or some other tight toleranced item, there by, creating more problems then curing. At the time many of the "flushing machines" ran higher pressures then what the tranny normally operated...so it did do its job.

So by doing the back to back filter and Fluid changes it got the dirty filter and most of the old fluid out right away on the 1st shot...new fluid & filter and short drive hopefully let whatever was left floating in the remaining fluid got trapped/ caught in the fresh filter under the trannys normal operation. so the 2nd filter and fluid exchange stood a better chance of getting nearly all the old fluid out and a fresh filter to to run it all through...that was nearly 40k miles ago and I have not had a moments trouble with the transmission. Like mentioned earlier yes it is extreme.

short answer IMO is yes do it. especially if you plan on towing anything

 

Thanks for the replies. I thought about having the dealer do it, since they vacuum all of the fluid out, including the torque converter. Bad idea?

 

no its not a bad idea...just be cautious as to how it gets done. Ask how high of pressure are they running?

If you go that route...I still would request a pan drop and filter change prior to the "vacuuming/exchange" of fluid. then drive for a hour or so, making sure that you run through all the gears and do the filter change again & refill the tranny fluid
some of those torque convertors had a drain plug...but I'm not certain that yours does.

It is not a hard job to do...just messy

 

Thats an understatement. I have a large drainpan, but still got about a qt of fluid on the ground.
This is one of the reasons I put a drain plug in mine. I have drained it once since putting the drain plug in and it is so simple now.


I personally don't like the flushes. Yes it gets all the fluid out, but it leaves a dirty filter in there. While the filter does not filter fine particles, it still is dirty.

The 3 drains (with filter change and installing the drain plug the first time) I am doing is getting probably 90% of the old fluid out, and total cost will be around $80 and 2 hours time.
IMO just as good as a flush (or better with the filter change).

 

both a flush and a filter change is the best way to go IMHO. i have performed many flushes on a wide variety of vehicles. never had i ever had an issue. what i do is the flush first and then the filter change.

 

the concern is that a "POWER flush" can loosen up crud that has settle in the corners and could then get into the spools and "stick"... would be nice to get all the crud out of the corners, but not at the expense of putting it into the valves... If your just "flushing" by pumping a low pressure flow thru the system. that might be different.

 

This can be accomplished very easily.


Drop the pan, install a new filter. Button it back up.

Remove a cooler return line from the radiator. Place a hose over the end and put the other end in a pail.

Pour 4-5 quarts of fluid in the filler tube and fire it up.

Keep adding fluid until what is exiting the cooler line is clear.

Shut the engine off, reconnect the cooler line, fire it up and bring the fluid level between the full and add marks.

 

I had A BG power flush done on mine. The only pressure it uses is what the truck itself generates. It is done through the cooler lines and has a site glass to watch the change in the color of the fluid. The fluid is prepackaged with the correct amount for the flush and refill. My trucks transmission never before shifted as smooth as it did after the flush. Ford uses the same method of flushing with the exception that they add BG concentrate to Ford fluid and BG uses their own fluid.

 

^^^^^^
This is the best way to do it IMO. I did my two Grand Cherokees this way.

 

I prefer a pan drop and filter change every 30-50k myself but have done many flushes and pan drops where I used to work. We would run the flush machine then drop the pan to change the filter. I like the idea of installing a drain plug in the trans pan. I have been considering it for my truck.