Funny you should ask! It is my opion that synthetics are best. Out of the synthetics the higher the concentrations of TMP and TPE the better! It is my opion that by reduceing carbon, ash, varnish and sludge deposits the seals, ring pack, egr valve and guides will live a long and happy life.
I am sure that additives like Lube Control, Auto-Rx and Nuetr 131 all help as well. I would rather have an oil that does not generate alot of waste to deal with!!
Man I hate when companies go cheap on things like that, especially valve seals...it such a simple item to just use better quality!!! But when it comes time to replace it, it's a pain in the @$$ and it cost a lot too...it's at the point that it would be easier and cheaper to change the whole head than replace the seals and adjust the valves and lube the cams...
An consistantly I've heard people with the 5sfe engine start getting smoke at start up at 80K, my coworker has a 95 Camry 5sfe and it has 83K, it only smokes if he leaves the car without driving it for more than 2 days, probably enough to let oil seap throught the seals.
My valve seals are original on my toyota cressida with 250,000 miles and show no sign of giving up.
I would say top quality seals and frequent oil changes with dino Castrol GTX. I have changed the oil 3000-5000 with various weights over its life. No additives except marvel mystery oil, when I had a valve tap at 190,000 which then went away.
Oh yea no doubt the cressida had great seals, plus it was their luxury line at the time. It just seams that Toyota and other Japanese Auto companies are finding places to cut cost to increase profit. Like during my year of camrys they used crappy General and Dunlop tires, In the 97-99 they used crappy strut mounts..seams like plastics is where they are getting cheap.
In the 70's/80's the Japanese Auto companies were striving to create a market in the US, now they do, they are overly confident and want to start getting cheap..that sucks...but it keeps us buying cars I guess.
I don't agree that synthetics will prolong valve seal life especially if the seal is a bad design. I had a 93 S-10 4x4 which I bought new. I used Castrol Syntec 5W-50 in it from new and at about 30,000 miles my valve seals were shot. The truck was smoking on startup and using oil. When the dealer replaced them under warrenty, they said that one seal was actually missing. I later switched to 5W-30 Mobil 1 but the truck never did quit using oil.
Sure your Toyota Engine + GTX is not sludged?
After reading this board two conclusions I have drawn are that although long lasting Toyota engines are sludge prone.
And that even frequent changes of GTX will form sludge and gums in the long run.
Leading me to ask that do you run Mobil 1 or Amsoil at all??
I think cleanliness is the key to good valve seals. Good oil, good gas and engine in good tune.
Sure, time and miles will wear the seals, but if you have carbon grit - wow it'll tear them up.
I think Lube Control is a good product for preventative action and AutoRx for corrective action....although some cars seem to depend on crud to make good valve stem seals, temporarily!
>>>The truck was smoking on startup and using oil. When the dealer replaced them under warrenty, they said that one seal was actually missing.
Rats, another belief shattered. I thought synthetic oil was a mechanic in a can, and would replace missing seals or gaskets!
Dr.T, one item was a typo "TPE" should have read TME!! I will include other common ester abreviations wich I mis tpe all of the time.
All of the above esters = good stuff in an oil!!!
The way I understand it Redline uses TMP,PE and DPE in varying amount for a total of 60% ester. THis is all speculation and hersay. Seeing how Redline will not coment I am at the mercy of those on this site that are in the industry to piece this together!
Taidaima, I have a '93 Camry with the 5sfe 4 banger that now has 235000 miles on it. It has had Mobil 1 since new, changed every 4-5000 miles, and is just now starting to smoke on start up when it sits for a few days.
SumerDuckman: Thanks for the statement of relief, I drive about 8K-10K/year so when it gets to 235,000mi it'll be a 20something year old car...
Hmm I wonder if they used better seals in 93' I can ask. Anyways, sounds good..looks like synthetic does help conditioning seals...also with that mileage..you probably drive every day..I only drive the car on the weekends, so most of the time it seats without action..could be better could be worse...
Only time and mileage will tell =)