I recently bought a used 2001 F-150, 4x4, 5.4 as a spare work truck to have on hand for emergencies. Not knowing the complete service history, I've spent the last couple weekends doing all of the recommended preventative maintenance from the beginning to the current millage.

This weekend I was working on all of the fluids changed out, by so, I had Mercon ATF, Mercon V (+ tran filter), front and rear gear oil, engine oil, and antifreeze lined up on the work bench.

I was doing two tasks at one time replacing the starter motor and draining the front differential. My wife came out to the garage while I was under the truck and the differential was drained and being lazy and not wanting get out from under the truck to get the gear oil I asked for her help.

I already had a hose with a funnel attached ready to go. I had her feed the hose down through the driver side wheel-well and I put it in the fill hole. I told her which two bottles of gear oil to use and pour down the hose for me. I noticed right away that the fluid was "RED" and thought it was a little odd, but not having used this type of gear oil before I passed it off as one of those many weird Motorcraft things.

I put the fill plug in and finished up with the starter. I didn't have time to do the transfer case today, so I pushed the tools to the side and started the engine to test the starter and pulled the truck back about 15' out of the garage and forward about 20' onto the RV pad.

As I walked into the garage I noticed that my wife poured Mercon ATF down the hose. As fast as I could I put a bucket under the front differential and pulled the drain plug.

Here are my questions:

1. Will the mercon ATF have done any damage being in there for that short of time and not having really drove it or put it into four-wheel drive?

2. Any suggestions on cleaning/flushing out all of the ATF? I'm thinking of running a couple gallons of 75W-90 GL-5 gear oil through it to flush it out. Will this save my *** or what else do I need to do?

Thanks for your understanding!!!

 

lol funny story but no you have nothing to worry about. unless you drove it in 4x4 for a long period of time no damage is done at all. if anything it just gave it a good cleaning dont worry about flushing or anything just drain and refill with oil it wont hurt anything. atf is pretty thin so 99% of it will just drain out.

 

definately a funny story ! I could see something like that happening pretty easy, but no worries bud, no damage done.

Like Paralyzer already said, unless you drove around in 4x4 for a long period of time (and don't want to admit it) you'll be fine.

If it makes you feel better (and I would probably do this) run your normal gear oil around in there for awhile, try and get 100 or more miles in 4x4 and then swap it out again.
Highly doubt its nevessary in any way, but its something that I would do, just to FEEL better about it.