Transmission drain and fill

[barkingspider]

Originally Posted By: PumpPusher
I think I'll pull the plug, drop the filter, and top off. Should get about 7 qts this way. Repeat later. Does Wix make a good trans filter? Seems like its the easiest to get to.


This sounds like a good plan. Wix is a real good filter. I have one in my truck.

 

[daman]

Go for it, I've serviced(line flush method)many high mileage transmissions in my day and never had one problem with them.

 

[JC1]

Originally Posted By: Or
Originally Posted By: FastLane
Dump the pan and change the filter. Top off with some Maxlife.


+1. There's likely a lot of friction material in the pan and shavings on the magnets.

I did a line swap on a higher mileage car of ours. After a while I noticed the fluid getting darnker faster than it should have. I dropped the pan and cleaned out the muck I should have before putting 2.5 gallons of fresh fluid in it.

Also do your PS fluid at the same time; it's handy in my mind to do both together.


If you are paranoid, then do a drain and fill for the first service. If all goes well, do a second drain and fill along with a pan drop (cleaning the pan of course) and filter change. I've used Wix transmission filters and had no issues with them. Also used a magnefine in line transmission filter.

 

[PumpPusher]

Well I dropped the pan and changed the filter. There was not a lot of debris in the pan, just a little metallic sludge on magnet. Topped of with 8 qts of Valvoline Mercon V. I did learn that regardless of what the parts finder says, 7.3s with the 4R100 all have the deep filter. Two or four wheel drive, doesn't matter. I'll put some more miles on it and drain again.

 

[southernjeeper]

Originally Posted By: Reddy45
I don't claim to be an expert on this but I've heard in the past that you should leave the fluid if you're beyond 150k miles without a change.

The reason? By that mileage, you're going to have worn down the friction material on some parts in the trans. You may not be anywhere near a rebuild, but replacing all the fluid means you'll actually have a lot less friction available. Slippage may occur as a result.

Not my words, but I saw it mentioned somewhere.

FWIW, I used to own an 02 F150 with the 4R70W and it started to slip on me around 145k miles. I was diligent about replenishing the fluid with Mercon V and a new filter every 60K. I sold the truck before I had to deal with any trans rebuilds.

You might look into adding some Lubegard Red as a preventative measure with that many miles. It has a good reputation as not just snake oil.



If transmission fluid is brown and/or smelled like it is burnt. CHANGE it!


Keeping track of OCI on the transmission is wayyyy cheaper than a transmission rebuild or a new transmission.

I just change my trucks fluid twice a year. Hot down here. And heat is terrible for transmissions.