Pennzoil HM vs Plat

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Sep 4, 2014
Burleson Texas
My sube has almost 170k, I will be using a Fram Ultra next week, and im trying to decide between Platnum (w/pureplus) or the bronze bottle high mileage conventional.

Will the seal conditioner in rhe bronze bottle outdo the platnum for keeping my seals?

Not only that, which oil will keep it as sludge free as possible? PYB states that 5W-30 will remove 40% sludge in the first change.
Since you've already run the ST HM, I'd stick with a HM oil. You may get away with the PP not leaking, but why risk it in a 15 year old car.
I've used both of those oils, and I think they're great...

I would decide based on if your engine leaks or not.

If you are trying to control a burning / leaking situation, you may want to try the HM.
She doesn't leak a drop of oil, nor burn any. I've heard that it's a myth that synthetic oil will make your car leak, but idk what to believe.
It will not MAKE your car leak, but some people are weary about using it in older neglected engines.

It sounds like your car is pretty good with no leaks, etc...

I would try PP or PU and see if you like it
The last few oil changes have seen pennzoil and 25% MMO. Dropped MMO after finding rislone and seafoam.

Runs great, no noise, no smoke, no CEL, I want her to last as long as possible.
switching to a synthetic in a high mileage car might make your engine leak because: the sludge buildup will be broken down and cleaned away and if the sludge was covering up a leak, that leak is now exposed and you get to deal with that if you choose.. (however, switching back to conventional won't plug it back up).
Pretty cool how that myth gets flipped around the wrong way.
Curious if your engine did develop a leak (as a result of using synthetic oil) would it possibly reverse this development by switching to a HM oil ?
My son's 02 Bravada with 175k started leaking after it's last change when I put in some M1 extended drain oil that I bought which was being cleared out at KMart. We've had the vehicle for the past 110k miles and it's had it's share of HM & various synthetic oil over the course of it's life and it never leaked. Strange it started leaking now (I put in a bottle of LubroMoly Oil Saver which stopped the leaking). The next oil change is coming up and I'll probably run a HM oil this time just to be safe. It's seems to run well on Valvoline HM.
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I would just run Pennzoil HM unless you plan to extend your oci beyond 7,500 miles. I run it in a '99 RS with 150k on it.

Hi SubieShane, at this point in your car’s life, we would recommend our Pennzoil High Mileage motor oil (especially since you are interested in keeping your seals in good condition!) Please feel free to private message us with additional questions! - The Pennzoil Team
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