At what mileage would you flush trans?

Power flush good or bad? Just drain & fill?

Always new filter?

Brand / wt recommended?

2013, Eco, screw cab, 41k.

 

Try posting here:


https://www.f150forum.com/f12/

 

Unless you've been towing extensively, heavy and hot, you're nowhere near needing a fluid/filter change. If its a normal driver I'd wait until at least 75-80,000 mi. I would not EVER power flush an auto trans. Drop the pan, change the filter and refill. Brand/weight : Read the owners manual.

 

But you wouldn't get half of the fluid out using this route. Torque converter holds a bundle of fluid which never gets emptied during manually changing it. Flushing it replaces all the fluid with new. It really depends on the color of your fluid as to which you should do.

 

You're correct. I have a method I use but didn't describe it, as its a little more complicated than some may want to attempt. It also should involve an assistant. Disconnect the cooler return line from the trans. and use a couple feet of appropriately sized rubber hose to run it into a bucket. Start the truck and pump out about a gallon, or until the fluid flow starts to sputter. Shut down and refill the trans. Do this a total of 3 times. Then drop the pan and change the filter. This gets everything out. The assistant is to watch the line in the bucket and stop you as soon as it starts to sputter. A little cavitation won't hurt the pump at all.

 

Neither will a flush. The better transmission shops use a low pressure flush that removes all the fluid without running the transmission dry, even if its for a few seconds.

I've been using an AAMCO shop on my last 3 F150's. Each were purchased with no less then 75 to 120K when this was started on them. I tow a camper often, and flush every 50K.

I've never had a transmission failure due to this type of flushing.

 

I used a similar method on my 2000 Expedition with the 4R70W. 13 years towing at or over GVWR and tongue weight, never a failure in the transmission.

Tell me, though, how does your method account for the thermostat in the cooler line?

 

Howdy.

We are talking aboot a 6R80 here... hence, here's the Service Manual fer same. It also describes a proper Fluid Exchange. Including how to address the integral thermostatic valve. And, coincidentally, how to measure the fluid level properly given the ridiculous nature and location of the l'il dipstick, lol.


http://edidist-public.sharepoint.com...%20Rev%201.pdf


BTW - it's simply not possible to 'reverse/back flush' a modern Ford auto tranny. The fluid flow path is one-way. That bit of info comes right from one of the fellers who designed the things - Mark Kovalsky. Use thet Googly thang fer more.


ETA: Oh yeah - fluid = Mercon LV.


MGD

 

This is the kind of info I like to gather that helps for us self doer's. Thanks for the post.