Piston Slap: Dreading "The Dreaded" ATF Flush?

Jackson writes:

I own a 2001 Nissan Maxima and a 2006 Corvette, both purchased new w/cash. I know the Maxima with 105,000+ miles has had two ATF services, which included the “dreaded ATF Flush”. So far the thing keeps running, only issue (unrelated) was a Cat replacement (99,000) and 3 O2 sensors around the same time.

The 2006 Corvette at 5 years and 42,600 miles is due for a coolant service and I see that the ATF service is 50,000 (harsh) or 100,000 (normal). So far expenses have been limited to gas, once a year oil changes and a set of tires at 26,000 due to some aggressive driving, aggressive factory camber settings and a shard of metal. It’s been spotless so far besides a squeaky roof panel which has been solved by periodic application of Super Lube to some contact points. Should I do an ATF flush for the vette? It would be a BG machine. It’s a warm weather commuter for me (42 miles round trip per day of which 26 is highway miles on which avg. speed 75 mph which is just 3 days a week).

I have taken it on 6 long trips over the years as well as weekend cruises. I do use the paddles about 30% of the time, but do not really hoon it so much the past 2 years after getting 3 speeding tickets in 6 month period…which I fought and is another subject. So please advise.

Sajeev answers:

The easier of the two to E-diagnose is the ‘vette. First, I really hope you ditch(ed) those run flat tires for some donuts befitting a Porsche 911, as that is what the Corvette deserved from the factory. And like much like Motor Trend’s game changing car of the year, the 1997 Chevy Malibu, the C6 Corvette comes with a sealed-for-life transmission. Which begs the question, where did you hear about a 50,000 mile service interval under any condition? Not that owner’s manuals are always right, but I seriously doubt you read that from your glovebox.

These gearboxes normally go 100,000-ish miles before servicing, and your driving habits are definitely within that realm. If you have the motivation, check the fluid’s condition using the link’s info. Odds are the ATF is fine, it should have a pink color with a slightly sweet smell. If it has black-ish bits and smells like a BBQ pit, change it according to factory procedures…and good luck with that!

Now about the Maxima: I question if an “ATF flush” is really something to dread. I’d be quite thrilled with your vehicle, if I were to buy it from you. The biggest plus in the flush’s favor is how it blows out all the old fluid from the torque convertor, which is essentially impossible in vehicles without a drain plug on said convertor’s case. While it doesn’t change the transmission filter, I’ve been told by several techs that this filter isn’t exactly that high tolerance in its filtering capability. Which implies…

…that doing the “dreaded ATF flush” when your fluid degrades essentially makes the transmission filter a lifetime service part. My thoughts are completely debunked over here, but I see their opinion as more applicable to car with more advanced transmission failures.

What say you, Best and Brightest?

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry.