Spktyr,
Your assertion that no Nissan belt has ever failed before its replacement interval is on its face beyond comical.
Nissan, while a fine manufacturer is not perfect, for you to claim that no belt in a Nissan ever made has failed before its mileage interval just shows flat out ignorance.
Again, You seem to keep putting words in my mouth. Whereas you are are claiming ALL when it comes to NO Nissan has ever had a timing belt fail before its recommended interval, I have clearly said MOST US cars that have interference engines and belts fall into the low end and most of those are older designs.
Why you believe Nissan can produce 100% perfection in its parts 100% of the time is beyond me. Parts fail, even great parts fail, even parts that have been inspected multiple times fail. You cannot produce 100% reliable parts 100% of the time, no one can. In case you missed the memo from the man upstairs... this world is populated with HUMAN BEINGS, and human beings are flawed, and any system developed by and run by human beings is also flawed.
All it takes for the best timing belt to fail is say, Oh I don’t know... a slight water pump leak... you ever seen what radiator fluid will do to one of those puppies? Even with if the belt had zero defects from the manufacturer its not going to last its life expectancy if exposed to anti-freeze.
I don’t know why you think Nissan is some God to the manufacturing and mechanical process, but they aren’t. Belts fail, it happens, the only thing good manufacturing and qc can do is minimize the failure rates, they cannot get rid of them. To assert that no Nissan belt has ever failed before interval is simply a ludicrous claim.
The timing belt on an inteference is the weakest part of an engine, in terms of its failure resulting in catastrophic engine failure immediately. Same is true of an interference engine with a chain, the chain is the weakest part that can lead to catastophic failure, but the chain is far stronger and more reliable than the belt.
Please come up with ONE documented example of this happening.
Google is your friend. I’ll wait.
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That said, the thing is that while it may happen, it’s so rare as to be practically never. You probably won’t find any entries on Google about the timing belt failing before interval. You can pretty much count on it not happening.
Now, after the belt is replaced the first time, if someone screws up the install all bets are off.
Finally, Nissan designs the water pump in such a way that if it DOES fail that it doesn’t leak on the timing belt - the weep hole for the pump is outside the sealed timing belt case on all Nissans.
Oil leak? Same thing, cam seals are more or less outside the sealed timing cover.
And since you fear to take the bet, I’ll point out that the top end domestics like Chrysler and Cadillac have, and in some cases still, use interference engines with timing belts. So your “low end only” argument doesn’t hold water.