Do I need to change transmission fluid/filter?

[92FOX]

I've got a 2006 Mountaineer, 4.0 AWD with the 5R55S tranny in it. It has 146k on it, and have owned the vehicle for almost two years, since 117k. The transmission shifts good and has no slips. I have no idea the previous maintenance done on the vehicle before I bought it, only what I've done in the last two years.

My question is, do I need to change the transmission filter? I went to remove the center drain plug (the T35 inside the 22mm main plug) to look at the fluid, but it was seized and stripped out. I now have no way of knowing the quality/state of the fluid inside the transmission without removing the entire drain plug, draining everything from the pan.

I'm a preventative-maintenance kind of guy, so I really want to drop the pan, change the filter and replace the fluid drained, but I also know that this can cause damage if the transmission has some internal issues I'm not aware of.

Any advice would be awesome.

 

[chefduane]

I don't think doing a pan drop and filter change will cause any problems. It's when you do a tranny flush with that many miles that issues arise. The flush can dislodge all kinds of sludge and stuff and foul fluid galleries. I would say do the pan drop/drain/filter change/new fluid and then if you are concerned about it, do another drain and fill (no pan drop) in a few thousand miles. You should be good to go. If the drain plug is stripped you might consider getting a new pan with a magnetic plug in it. And maybe a Magnefine inline filter.

I would, however, keep an ear to any timing chain rattles you might get on the 4.0. And I vociferously (!) agree on the preventative maintenance aspect.

 

[tripplec]

Definite yes but be 500% sure you are getting the correct fluid poured back in. A dealer should get it right where as a tranny shop has a barrel of fluid and you have not clue. Bring your own liters with you for a change in that case even a ford filter to get it right!!!

 

[92FOX]

Plan on doing it all myself. Mercon V per the owners manual, correct?

 

[tripplec]

Sound right unless there is an upgrade or better equivalent from Say Castrol or some major oil company.

Skip the shower and avoid the fluid bath as well. At least until you are done.

 

[92FOX]

If the drain plug is stripped you might consider getting a new pan with a magnetic plug in it. And maybe a Magnefine inline filter.

A new plug is like $10 at Oreillys, so that's not too bad.

What is the Magnafine filter? I was just going to get a standard Motorcraft replacement, is one better than the other?

 

[chefduane]

Magnefine is an aftermarket inline filter that it placed between the tranny cooler output and trans input line. Separate from the filter in the pan:

http://magnefinefilters.com/

I was going to put one on my '98 XLT but never got around to it. I have one w/ plumbing if you are interested.

 

[Tech By Trade]

Never a bad idea. I tow a camper all summer, so in the fall its part of my winterizing procedure. Your looking at about 5 quarts of Mercon V to top it back up, I usually pick up a sixth just to keep on hand. I had to change the plug last fall, OEM will run you around 15 bucks from your local stealership. There should also be a magnet in the pan so no worries on that front, just give it a good cleaning if it has some crud on it. I also gave the valve body a good torquing last fall and adjusted the bands while I was under there for good measure.

 

[tripplec]

2009 6 speeds don't have a plug. First I have heard in any north american vehicle having one. Lucky if you have one but as for us that do have to drop the pan then yes replace it.

 

[Tech By Trade]

The plug is actually how you fill and check the level in the 5 speed on the V6. You will also need one of these a. They are cheap on amazon. Also a suction gun, this one is from princess auto, but I'm sure Harbor freight has something like it down there.