Guys, I've got a question on my transmission. I acquired my 1994 F-150 last fall after my grandfather's passing. The truck has lived a garage-kept life from day one, so it still looks beautiful. It mostly sat from 2011-2019 while he was in a rest home, only being started and driven every few months by my uncle. I'm driving it several days a week now. Just went through a rough bout of issues with the MLPS (replaced twice before figuring out the connector was giving me intermittent problems), so it's had several rounds of not knowing what gear it's in and doing the whole rev up and hard shifting thing. To my knowledge, the transmission (E4OD) has never been serviced. Odometer is just over 79,000 original miles now. After the first couple shifts in the morning, most 1-2 shifts are fairly firm. My question is this (hoping especially to see Mark Kovalsky's take here): am I asking for trouble if I change the fluid at this point? When I got the truck, my mechanic recommended putting a can of BG ATC Plus in to renew the fluid, which I did, and it did improve overall shift quality. If I should change the fluid, should it be Motorcraft Mercon V, or something else, and any other recommendations for the truck? I want to keep this truck going for a long time!

 

I take it that BG ATC Plus is an additive to replace old worn out fluid? I’m not much on using that type of stuff. Yes , the replacement for MERCON is MERCON V. I don’t believe you can hurt anything by doing routine maintenance like replacing the filter and refilling the system.

 

Here is an article Mark published for how to change the fluid: Changing ATF Fluid in a E4OD and 4R100 transmission

 

Transmission fluid is similar to engine oil. You wouldn't change engine oil, would you? Of course, you would. And for the exact same reasons you should change the transmission fluid. The advice above my post is spot on.

 

Thanks everyone, especially Mark. I've read enough of your stuff to know you know your stuff, and that many others here do too. Now to buy all that fluid lol$$$.....

 

Mobil 1 full synthetic mercon V ATF is what's been going in mine. 308k miles and still working well.

 

In my experience that's the best fluid you can get.

 

Thanks to jobimi, mark and the others for asking/answering this question. I came here to search for it and all the information was 3 posts down. I also acquired a truck with 66k for my younger brother with similar circumstances as the OP. Spent today freshening it up with plugs, wires, oil, belt, etc. Tomorrow the transmission fluid/filter. All of the belts plugs wires were oem still. It is a 1 owner XL that is rust and almost completely dingless.

 

I had my trans rebuilt last year and switched to Valvoline MaxLife full synthetic when I put it back in. So far seems good. I did another fluid change after the first 500 miles on the rebuilt E40D, my thinking was any break-in debris would be cleaned out. The TC in my rebuilt trans does not have a drain plug, the OE one does, and you need to make sure to drain that as well if you want to do a full change.

 

Maybe it’s just me but I would be using the specific atf called for and not some multi-brand fluid.

 

I did what Mark had written up on my 93 and I have had no problems whatsoever. Takes a bit of time but I feel better knowing she has new fluid in her (as of about a yr and a half ago) and it is still nice and red looking.

 

What gasket and/or sealant do you guys recommend? Since mine's a '94 it doesn't have the reusable gasket, and from what I'm reading I can't necessarily just buy the reusable gasket for it (difference in the pan lip?).

 

No sealant just a rubber gasket carefully torqued down in a star pattern. Don't over do it or else it will leak. Mercon V XT5-QSM is good.