waltheraustin

I've read to do it every 30k to keep the fluid fresh. If we can find the feed to the cooler, it is possible to do it all at the same time but since I have only 30k, I'll probably do the filter and drop this time then use the mighty vac and put back in what I took out

RX1Cobra

That's how I did it on my old truck but it won't work on the new ones. There's a thermostat so the fluid needs to be up to temp before it will go to the cooler. Even if you wait until it's up to temp the new fluid will be cold so it will close again. Or that's how I understand it.

I plan to change the pan fluid every 50K. Can't decide if I want to siphon it out each time or drop the pan. And if I drop the pan do I add a drain plug? I know it's not changing all of it but should be enough to keep things fresh. I'll be doing this for the first time once it warms back up.

waltheraustin

That's exactly what I'm going to do but I'll be doing it every 30 to keep it fresh. I bought a mighty vac that pulls and pushes so should be helpful. I think they make a dipstick extension for under the hood so that would definitely help. I'd hate to run the fluid too long to cause me to rebuild or replace. I'm guessing the 10 speed isn't cheap.

Napalm

Despite the old mythos around flushing the transmissions. In the older gen slush boxes that had syncros and used the older style fluid yes with enough age when flushed would lead to particulates being pressed though the valve body and causing issues. biggest issue - often sludge from the pan would come up and get in the valve body - causing it to miss shifts.


These newer (anything newer than 2003) clean sheet designed transmissions were designed with flushing in mind. The ZF 6sp, the Ford 10R100, the GM 6L80e, 8L90E, the 6T55 the 8T65 etc etc. They are meant to be flushed and they use a newer fluid chemistry. You might notice that in the manual it doesn't even suggest removing the transmission pan unless there are noted codes or other issues with the transmission. In which case you are pulling the pan down to look for parts or metal.

NOTE the flushing procedures take the trans temp in mind - it has to be up to ____ before it should be hooked up to the machine - and it maintains pressure and flow rate while running at operating temp to get all the valves opened and new fluid pushed though the paths. Have you looked at the fill procedure if you do the pan drop - note it's rather tedious. since you have to check it at operating temperature also.

Not that there is anything wrong with taking the pan off - and cleaning it out - but you won't get the bulk of the fluid out and it won't clean any of the valve paths. So you will button it back up and drive around with some new fluid, some old fluid and some old dirt - and maybe cause it to collect. If you were to drop the pan - re attached - fill - run it on jack stands though the gears - drop the pan again repeat. you would get alot of the system.

Meanwhile and I don't know if the ZF does this - but I do know others do - you can put the vehicle in flush mode with the computer - and the TCU opens all the valves while in neutral, engine on, flush connected - and it cycles the valves and actuators during the minutes of the flush procedure. Again not sure if the ZF does this it would be in the shop procedures.

Just trying to clear up some misconceptions - the newer transmissions are quite different than from 15+ years ago.

ford4wd08

How are you supposed to refill if there is no dipstick?

I know my 2.7 Ecoboost 6 speed trans doesn't have a dipstick....

Bullitt427

There is a dipstick, just unconventional and under a plug. Same place you refill.

BadCon

It has a dip stick, its just super short and concealed by the large fill cap on the passenger side of the trans. You open the fill cap and a little plastic dip stick comes out. However a good rule of thumb, assuming you have no leaks, is to replace with the same quantity you drained out (so measure the drained oil). Gets you in the ballpark, then just get it up to temp and use the little dipstick. Remember you will be unable to put all of the new fluid it at once, you'll need to fill about 4qts or so (6r80) and then start the truck and cycle it through the gears, this will let the trans suck up some of the new fluid, then put the remaining fluid back in. Its not a terribly hard procedure, with the biggest risk being burning your arm on the nearby exhaust parts.

waltheraustin

So are you saying that the filter doesn't ever need to be changed? What are your thoughts on intervals?

Thanks for the info. Where if I can ask did that come from? I'm basing all of my info on my 2012 5.3 so it's definitely aged info.

Thanks again

RL1990

Nope, Nope and Nope.

Ford want the old fashioned drop and fill for changing transmission fluid. They only recommend flushing when their has been a repair/replacement. Even then it requires special equipment to heat the flushing fluid to operating temperature to open the transmission's internal thermostats.

ford4wd08

Good to know on the dipstick. I was just going off of the owners manual.

Doesn't the owners manual show a scheduled service of 150k miles for the trans?

I know this is a newer fluid compared to my old 07 Lariat with the old 4 speed on Mercon V.