Pennzoil Platinum Pure Plus and older seals

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I have a question regarding the chemistry of the new Pennzoil Platinum Pure Plus oil. I recently changed the conventional oil out of my 205k mile 2005 Honda Pilot and refilled with the new formula Pennzoil Platinum. Prior to this change, there were no signs of any leaks coming from the engine. Within a day the rear main seal developed a considerable leak. Significant enough that I parked the SUV until I had time to replace it this weekend. The old seal did not show evidence of excessive wear or damage, and the crank is in great shape. The motor is again drip-tight with the new seal. Is it the change in chemistry that could have caused the rear main seal to leak?
 
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Not sure, but I had a similar experience with my 2001 Accord - I switched to Pennzoil Ultra and a rear main seal drip showed up almost instantly! It was my first oil change with the car which I bought at 145K I personally was thinking that the previous owner must have been running high mileage oil (swelling the seals) so when I switched over to a synthetic, the seal contracted and allowed the drip. I always regarded the "switching to synthetic will make your car leak" saying as a myth but it certainly seems to be the case here. PS, I'm NOT saying it CAUSED the drip. I'm just saying that its co related at least in my scenario.
 
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MrQuackers

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I have this wonder oil in my car too. GTL basestock, maybe LTG when used in the engine (LOL), seeking out any escape route. It sure runs great in my SL2 and I recorded my first 40mpg trip using PP GTL
 
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For the seal to leak shortly after the switch to the synthetic oil (you haven't mentioned the grade) is likely due to the oil being lighter and with a fresh high dose of detergents that cleaned away some [censored] that was preventing the seal from leaking. Anyway, you've installed a new seal and the engine is "again drip-tight" so enjoy the switch to a premium synthetic.
 

Jim_Truett

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Originally Posted By: CATERHAM
For the seal to leak shortly after the switch to the synthetic oil (you haven't mentioned the grade) is likely due to the oil being lighter and with a fresh high dose of detergents that cleaned away some [censored] that was preventing the seal from leaking. Anyway, you've installed a new seal and the engine is "again drip-tight" so enjoy the switch to a premium synthetic.
It had relatively fresh 5w-20 bulk fill from the Honda dealer. I used 5w-30 PPPP because it was already on my shelf. No signs of existing leak in bell housing or on trans cover plate. (this was a recent purchase from a local Honda dealer even though high miles) The main issue I have is the fear of running this oil in my '99 Acura 3.0CL, or putting it in my Dad's 2003 Odyssey. Both have similar or identical rear main seals and housings. I have been running the old formula PP for years in my vehicles with great success. I will probably avoid the GTL base in the other vehicles for now.
 
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Stick with a quality conventional or blend if the syn is causing anxiety and more importantly, 'revealing' leaks.
 
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Originally Posted By: CATERHAM
For the seal to leak shortly after the switch to the synthetic oil (you haven't mentioned the grade) is likely due to the oil being lighter and with a fresh high dose of detergents that cleaned away some [censored] that was preventing the seal from leaking. Anyway, you've installed a new seal and the engine is "again drip-tight" so enjoy the switch to a premium synthetic.
+1, I agree.
 
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Originally Posted By: CATERHAM
For the seal to leak shortly after the switch to the synthetic oil (you haven't mentioned the grade) is likely due to the oil being lighter and with a fresh high dose of detergents that cleaned away some [censored] that was preventing the seal from leaking. Anyway, you've installed a new seal and the engine is "again drip-tight" so enjoy the switch to a premium synthetic.
+2 Many times just leaving it alone and ignoring it is the answer. A lot of the time it just clears up on its own as long as the seal isn't physically damaged.
 

Jim_Truett

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Originally Posted By: Trav
+2 Many times just leaving it alone and ignoring it is the answer. A lot of the time it just clears up on its own as long as the seal isn't physically damaged.
I had considered that, but with the amount of oil that was starting to coat the undercarriage I figured $20 in parts and a few hours of my time was what it needed. I just hate leaks like this on my vehicles.
 

AHC

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2001, 5.4L, F150, 75,000 miles, 5W-20 syn since new. My truck developed a slow head gasket oil weep at about 50K miles. It's a known issue but does no harm so no recall. Not too bad of a leak but my WIFE started smelling burning oil (from the manifold) outside the cab. I knew it was time to start cleaning it up more frequently. But I wasn't going to spend thousands $$$ on new gaskets when it was doing no harm. Plus the truck runs like a raped ape. Then Dexos 1 came out with its improved seal compatibility. No more smell. I can't even tell if it's weeping anymore. Worth noting - I've used Amsoil, PP, and Valvoline Syn, all Dexos 1, no leaks. So in my case, did staying with syn cause the weak? Nah, Ford did. Did Dexos 1 help? Well, the only thing that changed was Dexos 1. I dunno, but Interesting none the less. Good on ya for changing your own seal. Impressive. thumbsup
 
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