View Full Version : Frequent Oil Changes Kills Your Cat?


Oranje
08-15-2009, 09:53 PM
Anyone ever hear of this?

Article Link: (http://finance.yahoo.com/famly-home/article/107429/the-great-car-maintenance-upsell.html?mod=family-autos) "That oil change? Turns out every 5,000 miles is often enough. New oil has chemicals that eat away the catalytic converter, says Donny Seyfer, a Colorado-based certified master technician, and changing oil too often can damage that pricey part."

Time to give up the 3,000 mile oil change?

04RX8man
08-15-2009, 10:52 PM
^Uh never EVER heard of that.......should not make a difference at all unless you're burning a ton of oil....I"m sure my premix is worse for the cat than changine the oil every 3k miles......

nycgps
08-15-2009, 11:40 PM
Anyone ever hear of this?

Article Link: (http://finance.yahoo.com/famly-home/article/107429/the-great-car-maintenance-upsell.html?mod=family-autos) "That oil change? Turns out every 5,000 miles is often enough. New oil has chemicals that eat away the catalytic converter, says Donny Seyfer, a Colorado-based certified master technician, and changing oil too often can damage that pricey part."

Time to give up the 3,000 mile oil change?

All oil kill CATs, this isn't freaking news ------- its just that MANY people doesnt know that :) --- wow they made a news out of that.

but not changing oil because of CAT is just stupid. there are zillions of people changing their oil every 3K miles with CAT thats over 150K miles and still going strong.

it all depends on how good the engine handles oil.

TrochoidMagic
08-15-2009, 11:57 PM
Anyone ever hear of this?

Article Link: (http://finance.yahoo.com/famly-home/article/107429/the-great-car-maintenance-upsell.html?mod=family-autos) "That oil change? Turns out every 5,000 miles is often enough. New oil has chemicals that eat away the catalytic converter, says Donny Seyfer, a Colorado-based certified master technician, and changing oil too often can damage that pricey part."

Time to give up the 3,000 mile oil change?

it really isn't that far fetched. and it may also be very true...depending on the formulation of the oil used!

as some of us may knovv, oils are tested to pass and graded thru API, but they are also formulated vvith emissions in mind. hence vvhy some hot-rodders may have a brand loyalty to a certain synthetic oil they like, be it SL grade over any of todays SM grade oils.

only vvay to find out is to have ur oil sent to a lab to check for the best additive package, vvhich some additives may be bad for ur cat.

motorcycle oils, in this respect, have upper advantage in vvear quality over motor oils. and i do believe (correct me if i'm vvrong) are less strict on certain amounts of vvear additives they allovv.

BUT EITHER VVAY, you don't have to be an master tech to pick having to replace a cat early over an engine from dirty oil being injected in ur precious rotary motor.
both are pricey, but vvhich is easier to do?

your choice.

04RX8man
08-16-2009, 12:02 AM
^a cat of course....but which will fail first......a cat with 80k mile warranty or an engine with 100k warranty....and whcih will mazda fight about more!!!.....I no matter what will still be chagine oil at 3k to 3.5k miles forever...the additives wear out in oil ESPECIALLLY in a HIGH temp and HIGH RPM engine like the rotary.....I live my life by the "a redline a day keeps the carbon away" and usually ALOT more than once do I hear that AWESOME beep....so my oil takes abuse on the street and the strip...so 3k I'll still be changing it...

nycgps
08-16-2009, 12:33 AM
I will treat this "news" the same way as that FOX news couple months ago, the one about "Street Racing" and all that, "with the press of a button it turns this into a race car" "this intake will greatly increase the horsepower" blah blah blah blah blah.

in the other words, yeah, another utter bullshit "news", and hmm yeah this so called "master tech" is so proud of being on TV with his full of crap.


But parts are now built to last longer

that is 100% NOT true. I often find older cars to be MUCH MORE reliable than today's cars.

Krazed_Rx8
08-16-2009, 12:46 AM
I'll stick to my 3k mile oil changes! :wiggle:

TrochoidMagic
08-16-2009, 01:01 AM
I will treat this "news" the same way as that FOX news couple months ago, the one about "Street Racing" and all that, "with the press of a button it turns this into a race car" "this intake will greatly increase the horsepower" blah blah blah blah blah.

in the other words, yeah, another utter bullshit "news", and hmm yeah this so called "master tech" is so proud of being on TV with his full of crap.




that is 100% NOT true. I often find older cars to be MUCH MORE reliable than today's cars.

true in some sense. i diagnosed my vvife's PS pump failure due to the plastic return tube. they vvarrantied the pump, and i replaced the tube for a metal one out of my older honda.
^a cat of course....but which will fail first......a cat with 80k mile warranty or an engine with 100k warranty....and whcih will mazda fight about more!!!.....I no matter what will still be chagine oil at 3k to 3.5k miles forever...the additives wear out in oil ESPECIALLLY in a HIGH temp and HIGH RPM engine like the rotary.....I live my life by the "a redline a day keeps the carbon away" and usually ALOT more than once do I hear that AWESOME beep....so my oil takes abuse on the street and the strip...so 3k I'll still be changing it...

i hear ya brotha, i ain't doubting ya. i change mine betvveen 2k-2500.
i'm even contemplating trying out throvving some motorcycle oil in there. maybe...

05rex8
08-16-2009, 01:03 AM
^is your "w" key broken?

vvhats vvith the v's?

Red_Fox
08-16-2009, 01:15 AM
^^^ I"ll let you all know when my cat goes out thank you very much so i'll stick to every 3k miles

alz0rz
08-16-2009, 01:32 AM
^is your "w" key broken?

vvhats vvith the v's?

lol that was driving me nuts too :Freak_ani

ASH8
08-16-2009, 05:22 AM
vvhat BS

Flashwing
08-16-2009, 05:45 AM
Sounds like everyone hit on the good points. How much oil is making it into your exhaust will be the major factor in cat failures as well as the formulation (like major ZDDP content). However, the change interval isn't going to effect cat life one way or another from where I sit.

That's why I say running a catless pipe in the RX8 is the best thing you can do if you can get away with it. You can run whatever OMP injection or pre-mix amount you want without worrying about killing emissions parts which can cause damage to other parts of the car.

SARRAS
08-16-2009, 06:41 AM
it really isn't that far fetched. and it may also be very true...depending on the formulation of the oil used!

as some of us may knovv, oils are tested to pass and graded thru API, but they are also formulated vvith emissions in mind. hence vvhy some hot-rodders may have a brand loyalty to a certain synthetic oil they like, be it SL grade over any of todays SM grade oils.

only vvay to find out is to have ur oil sent to a lab to check for the best additive package, vvhich some additives may be bad for ur cat.

motorcycle oils, in this respect, have upper advantage in vvear quality over motor oils. and i do believe (correct me if i'm vvrong) are less strict on certain amounts of vvear additives they allovv.

BUT EITHER VVAY, you don't have to be an master tech to pick having to replace a cat early over an engine from dirty oil being injected in ur precious rotary motor.
both are pricey, but vvhich is easier to do?

your choice.

The 'W' key is top left - next to the 'Q'...

04RX8man
08-16-2009, 11:47 AM
vvovv that vvas bugging me too!

TrochoidMagic
08-18-2009, 03:12 AM
haha...

really sorry about that. i think its just to hard to have to copy and paste the letter for that broken button every time i start up the computer.

and YES, it is broken.

Jon316G
08-18-2009, 03:15 AM
really sorry about that. i think its just to hard to have to copy and paste the letter for that broken button every time i start up the computer.
and YES, it is broken.

Windows has an onboard keyboard.
Start -> Programs -> Accessories -> Ease Of Access (Vista and Win7)

nycgps
08-18-2009, 10:43 AM
Dude ... buy a nevv keyboard ...

vvhat sup vvith you ... you got shit loads of stuff for your car ... VVHY NOT YOUR COMPUTER ?!

Nubo
08-18-2009, 11:52 AM
Anyone ever hear of this?

Article Link: (http://finance.yahoo.com/famly-home/article/107429/the-great-car-maintenance-upsell.html?mod=family-autos) "That oil change? Turns out every 5,000 miles is often enough. New oil has chemicals that eat away the catalytic converter, says Donny Seyfer, a Colorado-based certified master technician, and changing oil too often can damage that pricey part."

Time to give up the 3,000 mile oil change?

What cat-killing chemicals are present in fresh oil that are not present after 3000 miles?


:bsmeter: