Conventional to synthetic

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CA
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Going to change my oil for the first time coming up, got a 04 Lexus rx330 140k miles Been fed whatever cheap dino the quick lube places had at 3-5k miles. I plan on changing it myself. Gonna try to go full synthetic with Supertech and a Bosch premium filter. Will run it for about 5k miles then change again and run a 7k OCI after that. Does that sounds like a good plan?
 
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sonoma
Yes, pretty reasonable oci. You may opt for a used oil analysis from blackstone at the 7k mile mark and make sure tbn is holding up. Every car is different, you never know. You may as well look into spun microglass filtration such as fram ultra as well. Paper degrades but spun microglass doesn't. I have even cut them open at 24 mos and they were still like new. Royal Purple, amsoil ea, fram ultra, wix xp and the most popular. Pair synthetic oil with synthetic filter for the win on a long oci.
 

JHZR2

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44,273
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New Jersey
Originally Posted by burla
Yes, pretty reasonable oci. You may opt for a used oil analysis from blackstone at the 7k mile mark and make sure tbn is holding up. Every car is different, you never know. You may as well look into spun microglass filtration such as fram ultra as well. Paper degrades but spun microglass doesn't. I have even cut them open at 24 mos and they were still like new. Royal Purple, amsoil ea, fram ultra, wix xp and the most popular. Pair synthetic oil with synthetic filter for the win on a long oci.
Agree it is reasonable. Paper works fine at 24 months as well. OP, is the engine in there one of the sludge monster engines? Does it smoke? If it has the risk of sludge, which many Toyota v6 engine sof that era did, I'd go slow. Supertech syn may have less solvency than others, but it may also clean. You might consider doing 1-2 short OCIs on an HDEO as well if sludge is a possibility.
 
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Kendall, FL
Just about every "Conventional" is now a Synthetic Blend. If you're keeping the intervals under 7k, I'd consider leaving things be and using a FRAM Extra Guard. But your plan sounds fine as well. Congrats on the purchase and... welcome
 
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1,793
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South Carolina
Your plan is solid and it sounds like it's had good oil changes in it's life. SuperTech is a fine oil but I would stick with 5k OCI's. I've switched numerous vehicles with 200+ k miles to synthetic with no issues (fingers crossed of course).
 
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6,408
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Wet side WA
I've run the Bosch premium filter on my 2004 Corolla with Castrol 5w-30 EP 7156 OCI and got a stellar UOA. I'd personally have no issue going 7K miles on change 1. Several good full synthetics on sale regularly. QSUD is also another one I've used and a good value.
 
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6,642
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South Florida
Originally Posted by CruiserRX
Does that sounds like a good plan?
No. You have a mild climate, so synthetic is not needed. Plus, you have a high mileage 15 year old engine, unknown maintenance history, probably quick lube bulk conventional its entire life. Id run a synthetic blend in the required weight. Probably Maxlife. Synthetic could start an oil leak, where there wasnt one before.
 
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AR
If your conventional oil has plugged up oil leaks - it could probably benefit from cleaning up the sludge. If a synthetic can do that - it would probably be good. You could always sludge it back up on purpose with a conventional.
 
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