My existing transmission is worn and I am replacing it.

Prior to installing the new one, is it recommended to flush the ATF lines and the coils in the radiator that cool the ATF to get rid of the old fluid.

If so, what products are recommended? Found Kooler Kleen at Napa - is it ok to use?

Thanks

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1986 300E (3/2002) Rear ended and totaled (10/2009)
2000 Xterra (5/2000)
1992 400E (11/2009) -Sold
1986 300E (12/2009) - Sold
2004 E500 Wagon (6/2013) - Sold