This time around we have a question about a pinging Cadillac STS and a discussion about transmission flushing.
Pinging 2003 Seville STS
Question:
My 2003 Cadillac Seville STS pings on light acceleration or deceleration primarily at or about 2,250 rpm. At times there is no pinging. Pinging not dependent on fuel octane. Dealer didn't fix. Could it be a MAS problem? or ??? Help!
Answer:
Depending on the milage this is an issue that should be under warranty so I would recommend having your Cadillac Dealer look at it before doing anything else.
There are a number of cause of detonation or "pinging". The engine may be running too lean, the knock sensor may be bad or there could be an exhaust leak between the engine and oxygen sensor (HO2S). You may also have a vacuum leak or a problem with the cooling system. There are many causes to be more specific with the information at hand.
Automatic transmission flush: good or bad?
Hello. I came here because I was surprised to hear on the Car Talk forum "never do a transmission flush." General Discussion Car Questions So I did some Google searches and finally, found this excellent explanation by Vincent Ciulla about "why" flushes might be dangerous: Do You Need To Flush?.
I don't know anything about cars. About 10 years ago, a Subaru dealer sold me a $100.00 transmission flush which guaranteed the transmission for the life of the vehicle. (The flush-machine maker then went out of business, big surprise.) And just recently, a local mechanic sold me another $100.00 transmission flush as "maybe" solving the problem of my second car stalling at every light when hot and anyway, was "good maintenance practice." (Did not solve the problem, but a better mechanic later did, by installing some kind of circulation pump for $60.00.)
And right now, my Google search led to several advertisements for "transmissions flush." Often they say, "Not recommended for all vehicles."
Most notably, here is a writer who honestly seems to believe transmission flushes are good, at least for Toyota trucks: Automatic Transmission Flushing.
He claims that:
- Premium grade synthetic transmission fluid is recommended. (This part makes sense to me.)
- A transmission flush does not use extra pressure and therefore is not dangerous. (No mention about "reverse flow").
- "Cooler Line" flush machine is not recommended.
- "Flush inlet" flush machine is recommended.
- Before flushing, examine if fluid is "rancid": dark, burnt smelling, with flakes or specs. If so, do not flush. The transmission is already doomed and "for unknown reasons" a flush is likely to make it fail immediately.
(Possibly the "unknown reason" is the clogging of the transmission with sludge as explained by Vincent Ciulla. Which sounds similar, by the way, to articles I have read about the possibility of the sudden dislodging of cholesterol in the arteries possibly lodging somewhere else, thus causing a stroke or heart attack!)
Most persuasive "pro-flush" argument: if you do not flush the transmission, a large amount of old fluid remains inside the transmission.
Most persuasive "anti-flush" rebuttal: just change the fluid + filter frequently (every 25,000 miles) and gradually all the fluid will be changed. (And it seems to me that if, in addition, long-life synthetic fluid is used, this certainly should do the job...?)
So, if Vincent Ciulla (OR ANYONE) would care to comment on the "Toyota Truck transmission flush" article--I would be very interested!
Answer:
I have read the article you mentioned and found it interesting. My first question about the author is what are his qualifications? Is he a transmission mechanic? Is he certified by ASE? What experience does he have with automotive service and repair in general? My feeling from reading the article is that he is someone who has a Toyota and is relating his individual experience and opinion.
First of all, no vehicle manufacturer in the world has ever recommended or required a transmission flush, or any kind of flush. If it is so important in keeping the vehicle in top operating condition they would be the first ones to recommend it. As a matter of fact most vehicle manufacturers recommend AGAINST them. In addition no vehicle manufacturer requires their dealers to have flushing equipment as part of their required tool inventory.
The only ones who recommend a flush of any kind are the shops that bought the flushing equipment so they can make a few extra bucks selling the service. This is, basically, a cure that was invented and needed a problem to solve.
As for the argument that you never get all the fluid out when you just drop the pan and replace the filter, that much is true. But under normal conditions and with regular transmission service that is not an issue. If it is an issue with some vehicle owners there are kits available that will allow you to put a drain plug into the torque converter for draining.
Now there is a great debate over natural or synthetic oils and fluids. My personal opinion is that the only people who use long life synthetics are the ones who are too lazy or too negligent to have regular maintenance performed on their vehicles. (Okay, I'm braced for the flood of letters now.) I have serviced every vehicle I owned, and more customer vehicles than I can count, on a regular basis using regular motor oils and transmission fluids and every one of my vehicles have gone well over 200,000 miles and one, a 1977 Datsun B-210, has over 600,000 miles on it.
Bottom line is this, if you service your vehicles on a regular basis; change engine oil and filter every 3,000 miles/3 months, transmission fluid and filter every 30,000 miles/2 years, coolant and brake fluid every two years your vehicle will never need a flush, synthetic oils or fluid and will last over 200,000 trouble free miles.
If you have a question or comment for me, you can e-mail me at autotechrepair at suite101.com.
