Dear Iron Chef,

Hope you're well. When was the automatic transmission fluid (ATF) last flushed? Old/dirty fluid can make for rough shifts. It is a good idea to flush the tranny ever 50,000 miles / 90,000 Km. See the site's FAQs for the procedure.

Is the ATF at the right level? A transmission low on ATF can also behave erratically.

Next, check the coolant overflow tank. If there's a pink scum atop the coolant, that shows the in-radiator ATF cooler has failed, allowing coolant to mix with the ATF. Water in the coolant attacks the glue, used to adhere transmission clutch-pack facings. Microfibers of clutch facing material can clog fluidways, creating rough shifts. Further, water turns to steam at transmission operating temperatures. Steam does not lubricate. If you see evidence of coolant in the ATF, at once: (a) replace the radiator and (b) flush the ATF, first with Wal-Mart ATf and then, 1000 miles / 1,500 Km later, with Synthetic ATF or a good quality standard ATF.

Finally, the kick-down cable may be binding in its sheath. See the FAQs for lubricating the kick-down cable.


Hope this helps.

Yours faithfully,

Spook