4R100 Drain and Refill? Am I two quarts low?

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Notice the F250 in my sig was getting some shutter at low speeds when turning. Checked my records and discovered it has been awhile since the trans was flushed and filled. This truck hardly comes out of the garage - we only put 1,300 miles on her last year. Thing is, when she does come out she is hooked up to a 3-horse Featherlite with two horses in the back. We also used this as our vacation vehicle back when we had our camper. She has towed to Florida, South/North Carolina and Tennessee several times. Time just got away from me and I've let this go longer than I should.

Went to Autozone and picked up 6 qts of Castrol Transmax Mercon V fluid for a drain. I pulled the plug and 6 qts came out of the bottom. After looking into it further, I notice in other forums that people were saying you should get 8 qts when doing a simple drain from the plug. Am I 2 qts low? I check the stick last night (lighting wasn't the best) and it looked like I was on the warm mark.

Hoping someone who knows these trans could chime in. I plan on checking it again today while its cold to see if I can get a better reading.

The fluid that came out was DIRTY! I let time get away from me. I plan on doing at least three more drive and drains - don't know how to do a full flush or else I would do that.

Probably going to order Motorcraft Mercon V or Havoline Mercon V from Amazon. Mercon V only fluid is getting harder to find - I'm not a fan of the multi-vehicle fluid.
 
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I like the Castrol (and have 10 quarts ready for when I put my aluminum transmission pan on my MGM), but the ST Mercon V from WM at $4.27/quart is a really good price, pretty sure it'll be WPP made. Never changed a 4R100, but, IMHO, there's no substitute for checking ATF HOT-don't want to risk overfilling & aerating the fluid!
 
For my ford transmissions, I check them while the trans is hot and in park.

I would go by the stick, perhaps that vehicle has a drain on the torque converter in the bellhousing, and you did not fully drain that when doing the service?

I'm not familiar with the 4r100 but some fords of that vintage had a drain plug on the converter that you could line up with a sight hole, to drain it.

I think the later ones got rid of the drain plug.
 
Mercon is not the correct fluid.
It needs Dexron. Check your manual.

I think it holds 18qts or so.
If you go to the Diesel Stop web site you can get the procedure to do a whole flush as written by a Ford transmission engineer.

Basically, disconnect the return line, attach a clear plastic line to it, run that out to a 5 gallon bucket that you can see.
Drain the pan and add 6qts, run the truck/transmission until you see bubbles in the clear line, repeat by filling the pan and running again, after the 3rd run add 5qts and check the level, correct as needed.
Shift the transmission through all the gears as you are running it.
 
It takes MERCON V.
Many owners have had luck with Valvoline Max-Life ATF (red bottle) and also Valvoline MERCON-V ATF (blue bottle) and they can be found at Wal-Mart for $18-$20/gallon.

Here is the DIY from a retired Ford Engineer who was part of the design team for your 4R100.

http://www.thedieselstop.com/forums/f47/...mission-198641/

A complete flush is not a difficult task if you follow the steps.

6-qts is on the low side for a pan drain...usually 7+.

The dipstick needs to be checked with the Trans Fluid Temp HOT...driving for 20-30 minutes depending on ambient temps. If you are towing then you probably have a TFT gauge...normal temp is 170*-180* F.

The small dimples on the white plastic tip of the dipstick are designed to hold ATF to assist in discerning the level. It is best to bring a white paper towel with you and carefully set the white plastic piece against the paper towel and slightly rotate it against the papertowel and see where the actual ATF level is at.
 
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Originally Posted By: KJSmith
Mercon is not the correct fluid.
It needs Dexron. Check your manual.


MERCON-V.

The correct ATF to use in the Ford 4R100 transmission in MERCON-V.

MERCON was originally called for and now MERCON-V is the correct ATF.
 
You at correct, been a while since I did it.

Mercon/Dexron3 is the same thing.
 
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I had a drain plug installed in my pan and do a drain refill every other year. It's usually 6 quarts if you stop as soon as the pan is drained and don't let the torque converter drain for a long period of time. Dex/Merc was the original spec. Mercon V was then back-speced for it. I prefer heavier viscosity than Mercon V and use a blend of Dex/Merc and heavy viscosity universal syn ATF to get the trans shifting I wanted.
 
Thanks for the link to the flush procedure. Checked the level again today before leaving for work and it looked to be full.

@ T-stick: good to here that you only got 6 quarts too, makes me fell better.

As for the ATF fluid, I'm going to stick with a mercon V specific fluid. Still leaning towards the motorcraft or Havoline. Havoline is a full syn while the MC is a blend (I think.)
 
Originally Posted By: T-Stick
I had a drain plug installed in my pan and do a drain refill every other year. It's usually 6 quarts if you stop as soon as the pan is drained and don't let the torque converter drain for a long period of time. Dex/Merc was the original spec. Mercon V was then back-speced for it. I prefer heavier viscosity than Mercon V and use a blend of Dex/Merc and heavy viscosity universal syn ATF to get the trans shifting I wanted.


MERCON was the original spec.
DEXRON III was proprietary to GM, right?

Although they were very similar?
 
Yes Mercon was the original spec though Mercon ATF typically carries a Dex 3 spec application also.
 
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