Shudder on Acceleration

After warming up, my '99 Taurus, 3.0 Duratec engine, 85K miles, "shudders" or shakes for 1-2 seconds during easy acceleration when shifting into 3rd and/or 4th gears.

I've tried new plugs and new plug wires, and checked around for vacuum leaks. I've changed the transmission fluid 3 times over 85K miles, the last time just after this problem started.

Any thoughts or suggestions? I'm hoping it's a connection or sensor and not the transmission.

Thank you.

You use the Mercon V fluid? I put in Castrol Mercon V and on the back of the bottle it says that it cures transmission shudder.

You use the Mercon V fluid? I put in Castrol Mercon V and on the back of the bottle it says that it cures transmission shudder.


Yes, I used Motorcraft Mercon V fluid, which also says it cures transmission shudder. I guess I'll have to take it in. I'll let you know what they say.

The local Ford Dealer said that the transmission technician and the foreman noticed 3 shudders:
Torque converter
Overdrive band
Brakes

They recommended replacing the transmission with a remanufactured transmission with a 3 yr / 36,000 mile warrantee, at $3562.79.
They could repair the existing transmission, but it also would be expensive and only a 1 yr / 12,000 mile warrantee.

I told them I would pick up the car, pay them the $90 diagnosis fee, and think about it.

I'm not feeling well.

I wouldn't feel well either, be sure to look at the Blue Book value before you sink more money into it than it's worth.

Did you end up having the dealer fix the problem? I had a really strange transmission problem that turned out to be a clogged transmission filter. The car made a screetching sound until the transmission fluid warmed up and could pass thru the filter. I had the filter changed along with the fluid. The noise went away but now I have a shutter from 25 to 30 and 35 to 40 mph. I just added a bottle of Lubegard (green cap) yesterday to see if will help. The verdict is still out.

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