Viscousity
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Lexus Test Driver
Joined: Apr 2008
Posts: 906
Likes: 6
From: California
Viscousity
I've heard that high mileage cars need 10W-30 instead of 5W-30 due to worn seals etc. I have 124k and my crank seal as well as some other ones were changed at dealer by previous owner at about 98k. It's time for an oil change for me. I'm using Royal Purple in my cars, should I go for 5W-30 or 10W-30? Btw I live in Nor Cal which is pretty warm here but I'm planning to go to snow in winter sometimes.
Thanks.
Thanks.
Lexus Champion
Joined: May 2008
Posts: 3,347
Likes: 6
From: RI
I've heard that high mileage cars need 10W-30 instead of 5W-30 due to worn seals etc. I have 124k and my crank seal as well as some other ones were changed at dealer by previous owner at about 98k. It's time for an oil change for me. I'm using Royal Purple in my cars, should I go for 5W-30 or 10W-30? Btw I live in Nor Cal which is pretty warm here but I'm planning to go to snow in winter sometimes.
Thanks.
Thanks.
Driver School Candidate
Joined: Aug 2007
Posts: 46
Likes: 0
From: CA
GS400RcrX, don't you have that backwards? thinner oil will give you the better milage. Many new cars such as ford use 5w-20 for better milage and less emissions. 10w-30 will be good for summer, where 5w-30 will be better in the winter as it flow better on startup.
If it ain't broke, done fix!! I wouldn't worry about changing weight until maybe your engine gets really loud or the weather changes dramatically.
I have 0w-20 in my car right now because previously, my daily commute was down the street so the engine did not get hot enough to provide maximum lubrication. Now that I'm back on the highway, I'm going to switch back to the original 5w-30.
I have 0w-20 in my car right now because previously, my daily commute was down the street so the engine did not get hot enough to provide maximum lubrication. Now that I'm back on the highway, I'm going to switch back to the original 5w-30.
usually for me, with over 100k+ miles i would use 20w-50 because the clearance of the piston rings and rod bearings are starting to wear down. If you use a thinner oil there's more play in the clearances on higher mileage cars. With a higher viscosity, you loose some gas mileage but overall protects the engine better, because heavier oil weight has less of a play in the clearance. 10w-30 is cool, if you want to use it year long, but 5w-30 is a bit thin on the lower end for me. Good luck.
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usually for me, with over 100k+ miles i would use 20w-50 because the clearance of the piston rings and rod bearings are starting to wear down. If you use a thinner oil there's more play in the clearances on higher mileage cars. With a higher viscosity, you loose some gas mileage but overall protects the engine better, because heavier oil weight has less of a play in the clearance. 10w-30 is cool, if you want to use it year long, but 5w-30 is a bit thin on the lower end for me. Good luck.
Using 20W-50 is ridiculous, in fact, if anything it's almost asking for faster failure... Because the oil is thicker, it will drive oil pressure up, but the downside to high oil pressure is lower oil flow, which means not as much oil gets to the cam and crankshafts, and, more importantly, not as much gets pushed into the tiny holes and such that feed the pistons and other small orifices...
Use what the manufacturer calls for...
As for the mention about gas mileage and oil thickness - the thicker oils will reduce fuel mileage - not much, but it may be noticeable...
As a reference, my SC is 400 miles short of the 200k mark, and I still use 5W30 in it... As Gsteg mentioned, unless the engine is making noise or smoking, use the OE recommended weight... When/if you do have to go to a higher weight oil, it's probably time to start considering a rebuild or a trade-in...
Driver School Candidate
Joined: Dec 2006
Posts: 46
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From: Ky.
Oil Viscosity
I've heard that high mileage cars need 10W-30 instead of 5W-30 due to worn seals etc. I have 124k and my crank seal as well as some other ones were changed at dealer by previous owner at about 98k. It's time for an oil change for me. I'm using Royal Purple in my cars, should I go for 5W-30 or 10W-30? Btw I live in Nor Cal which is pretty warm here but I'm planning to go to snow in winter sometimes.
Thanks.
Thanks.
