WAIT! STOP!<br>The friction modifer that was recommended is used in combination with the rear axle.<br><br>The notorious 4R70W automaic transmission suffers from TC-shudder and other ailmetns primarily because of the heat that is produced in the friction plates of the tranny.<br><br>One way to help alleviate this problem (and you must take action before you need a new tranny) is to replace the trans fluid with MERCON-V. Replace ALL the fluid, not just that 40% which is contained in the pan.<br><br>To get 100% of the fluid swapped you need to empty the TC. I find that a pain in the ass. So, I only get a little wet, by dropping the pan to get to the filter and clean off the magnet. Replace the filter, then head out to a "Jiffy-lube" type center and use their FLUSH SYSTEM. It costs about $100 when you specify MERCON-V. This is a back-flush, so I highly recommend installing a new filter before you backflush!

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