Doing an r/r on the rear main seal this weekend and while the trans is being pulled I'm going to service it as well. How much, and what type of, fluid do I need for the 4R70W?

I did some searching on here and I think I need 14qts of Mercon V. Is this correct? Or should I use regular Mercon? I still don't get the whole Mercon/Mercon V debate.......

Also, Instead of disconnecting the trans fluid return line and running the engine to pump out the old fluid couldn't I just disconnect the feed and return line and blow them out with the air hose? I could regulate the pressure down to say 20psi so I wouldn't blow the cooler apart!

How does this sound?

And one last thing. How much do you think would be a fair asking price for this truck? 94 F150 XL S/cab, 5.0, 4R70W, tow package, 3.55's. Factory aluminum wheels, good tires, chrome package, 40/20/40 bench from an XLT, 150K miles. The paint is in excellent shape. It has one small dent on the bottom of the pass door and both bumpers have some dents. Other than that she's straight...... rund great, uses a little oil between changes which is common. It's been well maintained too. I've owned it for the last 10 years. Trucks are kind of at a premium down here in South Louisiana because alot of the contractors are buying them up.

I hate to sell it but I defected over to the 7.3 PSD side of things and it's got to go.......

Thanks in advance.


John

 

I know for just a filter change it takes about 3-4 quarts. I have always ended up putting about 4 In my 1995 F150. My chilton's calls for 3 quarts. That never read high enough on the dip stick. My Haynes manual says the AODE or 4R70W fluid capacity is 12 quarts. The manuals I have also call for Dexron II / Mercon. I have always used Dexron III / Mercon. That is what I was told to use when our other F150 was new. I think Dexron V / Mercon is for the newer 97 or so and up body style trucks. We used it in my friends 2001 F150. I have been told numerous times that it is not a good idea to mix the fluids, so I would use either the II or the III not the V.

 

Not true, only use Dexron V / Mercon for all of the 4R70W. All manuals, and some Transmission Shops and Ford Dealers still do not know this. If you use Dexron III / Mercon in a 4R70W (AODE) you will get the shutter sooner or later. Ford has put the word out on this but some still have not gotten it. If you have Dexron III / Mercon in one you need to add a small bottle of Ford Limit-Slip additive to the Transmission. But I would still not mix fluids.

 

I have never totally flushed mine, just changed the filter. I've got 225000 miles on mine and never had a problem running Dex III. I do have the electronic shift improver since it hit 100K miles but thats it. I don't remember the Dexron V even being available the first couple of times I serviced the transmission in the 95 F150. I was told numerous times it is for the newer trucks.

Does anyone know why the Chiltons says Dex II or Dex III depending on how you read it. The Haynes says use Dex II. Even the dealer and my owners manual says Dex III. My transmission guy also says to use Dex III in my truck. He told us to use the Dex V in my friends 01 though. He has been building transmissions for 30 years. Why does the Haynes say to use Dex II?

Something else interesting. The Chiltons says the 4R70W capacity is 12 quarts, the Haynes says it is 12 quarts and my owners manual says it is 14 quarts. Is the owners manual wrong? Which is correct? I'm guessing that one is with and one is without tranny cooler.

Does anyone know what fluid came in our trucks when they were new?

 

Thanks guys,

I've changed the fluid once before, years ago. So, I'm thinking back then it was Dex III. I'll go back with that.

So basically it sounds as if the Dex V doesn't have the friction modifier in it like the Dex III does?

 

No, Dex III doesn't have the friction modifier in it.

 

To TexasGuy001

I have heard that Ford no longer recommends putting Dexron III in anything and they say use Dexron V as a replacement, but have not been able to verify this yet.

I know that you are not going to take my word for it so I suggest you re-post your questions over in the transmission forum and see what answers you get.

Here is the URL:

https://www.ford-trucks.com/forums/f...splay.php?f=69

 

Do you think that I should add some of the LS friction modifier to mine? If so, does it have to be Fords or can it be one from the auto parts store?

If you say that they recommend the Dex V, they probably do. I know that my buddies 2001 has a 4R70W in it. It does have a slightly different pan than mine, but that is the only difference I have seen. There must be some reason they decided to start using Dex V. As in it is probably better. I thought maybe some internals were different.

What is Dex II for? I have never even used it that I remember. I think I used the old type F in the 85 F150 351 C6 that we had years ago.

 

Here is a tsb basically saying Mercon V should be used most Automatic trannies from 1987 on and maybe before. Look at the chart on pg 3.

https://www.ford-trucks.com/lc/lc.php?action=do&link=htt...tsb06-14-04.pdf

For infomation on the LS Modifier please read this Thread:
and read the posts by ncranchero

https://www.ford-trucks.com/forums/s...d.php?t=464754

 

Texasguy-
dextron II was superceded to dextron III they are interchangeable

 

For some reason the above link to the PDF is not working, here it is again.

I do not know why it will not work in this Thread but seems to work in this one.

https://www.ford-trucks.com/forums/s...ight=tsb061404

 

First off I'd highly recomend using the Mercon V fluid, you are going to drain your transmission and converter and that should be fine.
Your trans will take 14 quarts doing it this way, I suggest putting in about 7 quarts then run the engine for about a minute then shut it off and add the remaining 7 quarts.
This Mercon V is good stuff and I'd spend my money on a known name brand.
I would also like to ask a question or two about your rear main seal job:do you know about the crankshaft saver??-its made to slip over the end of the crank to provide a new smothe surface for your new seal as the old one most likely has worn a slight grove in the crank and if the crank saver is not used the new seal will most like leak as well.
I am told that with the newer 1 piece seal that it can be changed/accessed without removing the oil pan-just by removing the flywheel-can you confirm this? Thanks!

 

I worked on it yesterday. Listen to the Chilton's manual. The fluid capacity is closer to 12 quarts. I stuck 13 in it and it's overfilled. I'll suck some out later. Worst case is it just blows out the vent. I used DEX III since that's what was in there before.

Now to the fun part. I pulled the trans only to find out the rear main seal was fine. It got changed anyway. My oil leak was from the pan gasket corner right above the starter. I've looked over the pan before and it was damn near impossible to see up there where the leak was. It was leaking out the corner almost where the last bolt is and running down the dust cover.

The factory gasket was a one piece silicone gasket with steel inserts ONLY around the bolt holes. I bought a Fel-Pro Permadry one piece molded gasket as a replacement from Autozone. I HIGHLY RECOMMEND THIS!!!!!!

With the oil pan dropped and hanging in the crossmember along with the trans out of the way this gasket was a breeze to install. It has a steel core AND inserts so just tighten it and go.

BTW, the crank was fine, no ridges from the old seal. And all you need to do for the rear main seal R/R is pull the trans, flexplate and blockplate.

Also, all I did with the exhaust was unbolt it from the manifolds. I left it hanging from the air hose and propped the front cat on a jackstand. Unbolting the exhaust makes it easier to get to the pass side bellhousing bolts and the trans lines. Not sure if you could pull it without unbolting the exhaust.

And lastly, why in the hell did Ford NOT put a drainplug in the pan. The TC has one but not the pan. If I would've had the time I was going to have one welded in....