Transmission fluid drain, and Mercon flavors

[nationwide]

I am about to drain my transmission ('05 F-350 KR Torqshift) by dropping the pan and changing the inline filter. I've done some reading on this (PowerStroke.org is an awesome resource) but am still confused about something.

The owner's manual is very explicit about not combining Mercon, Mercon V or Mercon SP as they are "not compatible". Granted, my Torqshift is supposed to have SP in it, but is there a way for me to be certain? I bought the truck used with 70K on the clock and it has 88K now. I don't have any records of what was done.

Will I frag the transmission by using SP if it did not have SP in it before? After all, I'm only trading out about half the fluid with this technique. And is there a way to tell what's in it now?

[Gringo_Tex]

Mercon SP was the spec when your manual was printed. It is now Mercon LV. Mercon SP, generally, is now more expensive than the new spec, Mercon LV. So go with the Mercon LV. Valvoline and Mobil are making ATF's which they say are compatible for Mercon, Mercon V and Mercon LV. I'm not sure how that can be given that Ford states that LV and SP are not compatible with Mercon and Mercon V. Clear as mud? Yeah. I think the safe thing to do is buy the Motorcraft Mercon LV.

[Gringo_Tex]

I should add, that it is OK to mix Mercon SP and Mercon LV, but do not under any circumstances put in Mercon or Mercon V spec'd fluids. It's for that reason, I am leary of the Valvoline and Mobil1 Synthetic ATF. And I'm a big fan of Mobil 1 products. While there is no way of knowing for sure what's been run in your truck before you got it, chances are it was SP or LV. I think you would be having issues if it were something else.

[2 stroker]

As Tex stated use this oil
Motorcraft fluid for Ford Lincoln Mercury cars and truck
up close Motorcraft TorqShift fluid XT-6-QSP Mercon SP
and here is the filters
Motorcraft transmission filter for Ford Lincoln Mercury cars and truck
The inline filter you mat need air or electric impact to remove then install by hand with a wrench or you may bend the pipe
2 stroker

[smokersteve]

I upgraded or updated to LV. Look at my link in my sig.

[tuckman]

I have mixed LV and SP with no problems, basically the same fluid just slightly different viscosity and pour point. Go with the LV unless you find somebody on kijiji or craigslist getting rid of a case for cheap (that is how I got the SP).

Note...Do not put LV or SP in your t-case, as per owners manual.

[Gringo_Tex]

When I called my dealer to price the ATF's, they quoted $4.83/qt for Mercon LV and $6.89/qt for Mercon SP. I was quite surprised at the difference in cost. I then price checked at Oreilly Auto Parts. They didn't carry LV but they still had SP in their local warehouse, and could get it for $4.00/qt. However, it is cheaper to get Mercon LV from Ryder Fleet Products online. Their prices for the filters are also quite good, and reasonable shipping costs. They carry Mercon LV for $3.97/qt and it must be ordered by the dozen. If ordering for from Ryder Fleet, it makes sense to get both Fluid and filters there to spread the shipping costs out. Dieselfiltersonline and k-manparts have good prices on filters, but so does Ryder Fleet Products.

That link to smokersteve's sig for the 13 qt fluid change is worth looking at to get the most fluid you can.

[nationwide]

Thanks for the replies, I was aware (through reading the posts here) about the switch to LV. I was able to get some SP at my local Ford dealer. I think I will just have to assume it is SP in the tranny now, unless someone knows how to identify the difference by color/smell/etc.