Will synthetic oil really sludge?

[Big Jim]

quote:

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Originally posted by bighead:
So, what is the reason for the Toyota and Chrysler sludge problems? Would running a synthetic prevent them from sludging? Or is that inevitable..

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Synthetic would certainly be much more resistant and with reasonable oil change intervals may be enough to keep this from happening. I most certainly would not go beyond 5,000 miles on these engines with synthetic.

 

[kenw]

quote:

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Originally posted by bighead:
So, what is the reason for the Toyota and Chrysler sludge problems? Would running a synthetic prevent them from sludging? Or is that inevitable..

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In toyota's case, poor marketing of a 7500 OCI in a very hot running engine.

168k 100% dino on my 97 v6 with no sludge BUT 4-5k oci.

most people "think" syn would do better in this particular engine, but so does simple dino with a increased oci. In fact, that was the single change that TMC made in subsequent model years: drop the OCI to 5k using the same exact engine and the problem has by all accounts gone away.

There are those (me included) that believe the real sludge issue is mostly forgetful drivers and hungry lawyers. The techs I've talked to that have seen the few real sludged toyotas say it is more than obvious that the oil is way too old. But public relations says instead of denying the issue, act like you care...

 

[TomJones76]

Maybe 30,000 is a reasonable oil change interval for this application?
We all realize that different drivers and different commutes call for different intervals. Maybe this is a "best case scenario" application where he's just barely getting the oil out before it would fail.

 

[moribundman]

I'm sure there are different types of "sludge." Moisture-induced "cappuchino" sludge is certainly not the same as black sludge, which happens when oil (and its VIIs) gets overly heated ("burns").

What type oil will begin to "burn" and form sludge at high oil temperatures first?