I(personally) would not recommend any kind of "flush" for the trans. A fluid/filter change might be ok, but nothing else. I'm not a big fan of the flushing trans syndrome, even tho it is good for my business...
TC shudder can happen on any vehicle, regardless of mileage. It is mainly due to calibration issues, and normal wear on the converter clutch, but a lot of times it is simply a fluid issue. Some trans fluids are just not compatible with the type of friction material used in the converter clutch. Regular maintenance is a big plus, but using a name brand, quality fluid is the biggest thing you can do to prolong the life of the trans.
One thing that causes lock-up shudder is simply the glazing of the friction surface on the clutch. This happens thru normal usage/wear. The "Shudder Fix" modifies the fluid composition to make the fluid more "slick", which eliminates the stickiness of the converter clutch, allowing it to apply smoothly, instead of grabbing/releasing.
Not exactly a scientific explanation, but hopefully it is understandable.
Lock-up shudder is not a sign that the trans is taking a doo-doo, but...if the shudder fix doesn't "fix" it, the converter will need to be replaced.
To verify that the vibration you are feeling is in fact converter shudder, drive the car at a steady speed until the vibration occurs. Then,
without lifting the throttle, gently press the brake pedal just enough to turn on the brake lights...in other words, just touch/move the pedal maybe 1/2". You should see the RPMs come up a couple hundred RPM. If the vibration/shudder goes away, the converter is the problem. What you're doing is dis-engaging the converter clutch. If the clutch is shuddering, then it will stop when you press the brake.
If the vibration/shudder does NOT change, then we got to look for another issue, but try this first, just to be sure. If the complaint goes away, then use the shudder fix, and you'll be good.
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Joel Adams
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