Need advice - tanny shudder not fixed by fluid change

[uzzo2]

i had to drive mine a couple of days after adding the lubegard approximately 100 miles before i felt the difference, it's been a couple of months now and have not had anymore problems out of it, hope you have the same results as i did from the lubegard

[Hartsock]

Originally Posted by wiswind

You will feel a bit of a "bump" through the powertrain when the A/C compressor kicks in.
It is also normal....particularly on hills for the engine to rev up just a bit when the A/C compressor kicks in......I don't know if it is shifting down a gear momentarily or just unlocking the torque converter momentarily.
The point of this "rev up" the PCM commands this to handle the sudden increase in engine load and prevent the engine from "bogging" down.
The A/C compressor is still engaged when the engine drops down in speed, but the engine is giving the extra power needed to handle the load.

After getting the tranny fluid replaced, and then going back again to get the filter replaced I went out for a 20 mile drive. Did not feel the shudder at cruising in that time, did not see the 200 rpm blip I had seen with the AC on.
But, when I put the air control to Vent, when the AC should not be running I began to see the 200 rpm blip again. Turned off the vent and the blip disappeared. What's up with that? Is the AC running when it should not be or something?

[dclatter]

New to the board ... this thread sounds like I wrote it!! I have an 02' Windstar and am experiencing the exact same issues mentioned here. Shutters between 40-60mph, seems to be around the shift point, is worse when a/c is running. I would add that I experience the same issue when cruising between 70-80mph as well.

I've done the plugs, wires, fuel filter, fuel pump relay, DPFE, checked EGR, checked PCM for water leakage (TSB) etc. Can't seem to get close to a fix. Scheduled an appointment at the dealer for Tuesday, but am thinking of cancelling after reading this post and hearing that the tranny shop couldn't find any issue big enough to diagnose. I have feared that all along, that I would pay $100 service fee to have them say they can't duplicate the problem enough to start diagnosing.

I noticed you post on the lubeguard was a few days ago ... any updates on how that worked out?

[uzzo2]

Originally Posted by dclatter

New to the board ... this thread sounds like I wrote it!! I have an 02' Windstar and am experiencing the exact same issues mentioned here. Shutters between 40-60mph, seems to be around the shift point, is worse when a/c is running. I would add that I experience the same issue when cruising between 70-80mph as well.

I've done the plugs, wires, fuel filter, fuel pump relay, DPFE, checked EGR, checked PCM for water leakage (TSB) etc. Can't seem to get close to a fix. Scheduled an appointment at the dealer for Tuesday, but am thinking of cancelling after reading this post and hearing that the tranny shop couldn't find any issue big enough to diagnose. I have feared that all along, that I would pay $100 service fee to have them say they can't duplicate the problem enough to start diagnosing.

I noticed you post on the lubeguard was a few days ago ... any updates on how that worked out?

it's worked out just fine for me, changed the fluid and filter, used mercon v fluid and the lubegard red. took a couple of days but since then no more shudder.

[Hartsock]

I must say the fluid replacement (Mercon V) and filter replacement seems to have taken care of the tranny shudder while cruising. Drove 300 miles this weekend and did not notice it at all. I'm feeling a little better about the transmission is this recently acquried WS now.