Transmission fluids

My g/f's 1994 Explorer needs tranny fluid. From what I can see online is that it can take either Mercon or Mercon V fluid. Problem is, we don't know what kind is in there to begin with. I bought a quart of Mercon V but before I dump it in there, is it okay to mix Mercon and Mercon V (in case that the fluid already in the tranny is Mercon and not Mercon V).

I tried searching online but there isn't really anything definitive I feel like trusting and was wondering if anyone here happens to know. Thanks.

A quick check of my sources says putting the Mercron V in should be fine, even if the fluid in there now is Mercron. The "V" is a replacement for the regular fluid.

http://www.fcsdchemicalsandlubricant...ission%20Fluid

If you have further doubts, have a flush and filter change done, then put in "V"

Thanks for the link, but it doesn't say if you can mix the two fluids together or not. We don't want to do the flush and fill because we are trying to get rid of it really soon and doing that (the flush and fill) would just be a waste of money at this point.

Sorry, I thought I had put the link up correctly. What I read is that you can mix them, as the "V" is a replacement. If you are getting rid of it, then don't worry.

I'll second that, Kev and Lance. Did that with my '92 Ford Aerostar. I had a situation where I was in the middle of nowhere and had to mix them, and I definitely knew it was old Mercon.

No harm done whatsoever and I did some hard driving with a trailer in tow up mountains the next day. I actually phoned up my mechanic to ask if I'd be OK and he gave me the green light. If a tranny's gonna fail, it'll be when it's taxed to the max and hot. It kept on going with that mix until the next summer, when I had a full, gentle flush of the transmission done (see the ford-trucks.com forum on how this is done!)

I think it'd be bad if you had Mercon V and added an old quart of Mercon as it would lack some additives, but the other way...you are probably improving it things somewhat.

BTW to bullet-proof the transmission (Aeros and Explorers have similar drivetrains if it's a V6), add a $100 transmission cooler in there. It actually improves the fuel economy -- did this to the Aerostar and on a journey I make every summer for over 500 miles all of a sudden I was getting more out of a tank of gas, as the transmission wasn't working as hard (hot).

I bought that van at 180,000 kms and took it to the crusher at 380,000 and it still ran perfectly fine. I just wanted a vehicle with working AirCon and a vehicle that I wasn't doubling the value of it by just buying a new set of tires! Ended up getting $450 for the scrap value of the metal of it because I couldn't sell it.