Should one change their transmission fluid if it has NEVER been changed and the truck has high mileage on it???

I've read about people developing leaks as the new fluid eats away at the seals and then they end up having transmission trouble. True?

I have 146K on my 4r70w in my 2003 F150 SCREW.

I was wanting to drop the pan, change the filter, drain the torque converter, and refill with either Mobil 1 synthetic Mercon V or Motorcraft Mercon V.


Is this a good idea, or should I just leave well alone? I do not have any problems thus far with my transmission.




DirtySCREW

 

I would. I would start off with a filter and pan oil change then I would wait 6 months or so. Then I'd go to a shop and get a complete fluid EXCHANGE not a flush.

 

I'd get the exchange done or at the very least drop the pan and change the filter. IMO new fluid is never a bad idea.

Have you had the truck since new and know for a fact it's never been changed?

 

Just have it flushed. But insist on knowing exactly what fluid they're pumping in, or ask how much for them to do it if you provide the fluid.

Most shops use regular Mercon and add friction modifiers to cut cost. If they try to tell you that it's just as good, bitch-slap them for me.

 

That is what I would do if it were mine.

 

You need an exchange machine to drain the torque converter - the 03's did not have drain plugs.

 

As usual,glc is correct.

I think they stop putting drain plugs on the converters in 2002.
I agree with MTMFord,get a fluid exchange and drop the pan. But,IMO,I would only let Ford do the fluid exchange.You can easily drop the pan yourself or let Ford do the whole thing.

 

IF you have access to a fluid exchanger save some money and do it yourself. It was really easy to do. The "hardest" part is dropping the pan and changing the filter.

I don't think I'd get a flush though.

 

No, I bought her close to 3 years ago with 132K on her. She has 146K now. They guy I bought it from was the second owner and was very addamit about using MOTORCRAFT 5w-20 Motor oil and a Motorcraft filter. He was very persistent saying to only use Motorcraft; which made me feel good as HE probably took pretty good care of the truck. First owner unknown.

But I know a LOT of people that change their oil on a regular basis or even over do the oil changes using quality oil and filters but neglect the transmission. SO I don't know if the truck has ever had the trans fluid changed or not.


GLC--I'm not doubting you as you have probably forgotten more than I know on these trucks....
BUT why do I have a rubber seal that looks like it would go to access the torque converter. I have never removed it but after reading several threads on trans fluid changes and what to look for, I went to see if I had what they said to look for. I did....I had the rubber plug on the trans. I just never removed it.


--DirtySCREW

 

There is an inspection plug but no drain in the TC get one when you over haul the tranny eventually.. You can tell if the pans never been off when you change the filter if the lolipop is still in the pan its never been off...