Folks, I think I screwed up ! I changed the oil and filter on my f-150 transmission, but I did not know that I could also replace the fluid from the torque converter, so I mixed new oil with old. To make things worse when I replaced the fluid on the transmission I used the Valvolin transmision oil meant for trucks and suv. I do not notice any difference in the way that the transmission operates but I am worried about any long run damage! Any suggestions would be apreciated!

 

What truck? What year? Which transmission? As long as you used a fluid with the correct specs it doesn't matter what the fluid was "specially formulated" for. I run Valvoline Mercon V in my 01 4R70W and it is smooth as silk. Never had any trouble with it after 15K miles with it in there.

 

Thank you for the response WVTRUCKER! the truck in question is also a 2001 f-150 with a 5.4 engine, but I have no idea what kind of automatic transmission I have. The oil I used for the transmission is Valvoline Max Life, its meant to be used on trans that have over 75,000 miles. My engine and trans only have 50,000 miles, but I tow a 22" boat so I figured this oil would fit the bill. Also the oil is for both mercon and dextron III. Would it be a good idea to drain the converter and refill with the same oil?

 

Your truck has the 4R70W transmission which uses Mercon V trans fluid. I would either flush the trans using the correct fluid, or drop the pan again and drain the torque convertor and refill with Mercon V.

 

Thanks folks, just to be on the safe side I am going to drain both the trans and converter. Again thanks for the input

 

You need to make SURE what tranny you have. Not all 5.4's came with 4R70W's, most came with 4R100 tranny's and those require Mercon, not MerconV. Door code and a search here will tell you what to look for and what tranny you have. Or you can use your window sticker if you still have it.

 

Not all the 5.4L F150s came with the 4R70w.

You need to figure out what tranny you have as it does matter.

Look on the door jam sticker that has all the trucks info. Under the box marked TRANS there will be a code.

The 4R70w is code U and requires Mercon V
The 4R100 is code E and requres Mercon

DO NOT mix them up, as the 4R70w needs a friction modifier that Mercon V has, and the 4R100 CAN NOT have friction modifiers which is what regular Mercon lacks.

Adrianspeeder

 

Make sure what tranny you have as mercon III and mercon V do not mix!!!!!!

 

There is no such animal as Mercon III, see my above post for the correct fluids...

Adrianspeeder