2005 Mountaineer Dleayed Transmission Drive

Been researching a bit and couldn't find any specific answers. The wife called me yesterday morning and said that it took a bit to get her 2005 AWD V6 Mountaineer with 134K in drive. Reverse works fine and it seems to shift perfectly. Well, this morning she said it took several minutes to engage then it clunked and went into gear. I hate this since I'm clear across town and she's got the kids. They're too young to push! The truck runs perfectly otherwise.

I've read that temperature may be a factor. This seems to fit since it's cooled down a little over the past week. In the afternoon, when I take a look at it, it seems fine. Guess it's nice and warm. Does the temperature affect the solenoid packs or is it the fluid and/or valve body?

I've read everything from bad solenoid packs to mere flushes as fixes. We had it flushed at about 60K. Would a flush be a somewhere to start or should I just take it to a transmission shop and go for the rebuild? Just don't want the call saying that she's stuck and it won't engage at all. But then again, I also don't want to take $2,500 out of Santa's funds right now!

First, I have a Lexus that has done exactly this for the last 150,000 miles. I drive it, not the wife so whole different set of concerns. I understand your need to fix this.

At first I was a bit confused by the AWD and V6. I'll assume the V6 with the 5 speed transmission, 5R55W. This is likely a Valve body "ish" problem. As it could also be the low/reverse servo. A little different from the selenoid packs. They start to hang up after a little wear and delay engagement or rarely fail to engage at all. You get to it by dropping the trans pan. This can be replaced fairly easily. Most people recommend replacing the O ring used on this servo with what is referred to as a double lip ring seal or Viton D ring. Slightly different shape. Be very careful sliding the servo plunger into the bore so you don't scratch it or it will hangup again.

If you can find a master transmission tech, they will usually agree to replace just the items you want replaced instead of a complete rebuild. This is much cheaper but will lack a warranty.

To find out more, search the Transmission forum. Look at the vavle body rebuild diary by Glacier. Much of the info here is for the 5R55E transmission but they are all extremely similar.

2004 mountaineer 6 cylinder 145000. AWD no power to wheels.
engine runs but while I was driving down a ramp onto the freeway... it was as if all gears went into Neutral... nothing not even reverse