Is 10W40 obsolete ?
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I believe the bad reputation of the 10w40 oils of 30 - 40 years ago is why we have the various 15w40 oils marketed at that weight today - and they are, by and large, excellent oils.
I have about 4 jugs of Syntec 10w40 in my stash, and was wondering which of my vehicles to use it in for a summer oil, and if that was OK. I use synthetic or synthetic blend in my two cars, dino in the truck. From what's listed in my signature, what would you guys recommend? Or should I mix it with some 5w20/5w30 to thin it down a bit?
I would use it in your truck.
Originally Posted By: aquariuscsm
Yeah,it`s pretty cool going on different country`s oil sites and playing around with their oil selectors. The US sites always give the generic 10W30 for my car. The Australian Pennzoil and Valvoline sites recommend 15W40 and 20W50 for my car.
The thinnest oil they spec for my enine in the UK and Australia is 10w40. I'm almost tempted to run a batch of 10w40 and see what happens to my gas mileage, engine operating temp, etc... My guess is i'd only notice that it was a little quieter.
Yeah,it`s pretty cool going on different country`s oil sites and playing around with their oil selectors. The US sites always give the generic 10W30 for my car. The Australian Pennzoil and Valvoline sites recommend 15W40 and 20W50 for my car.
The thinnest oil they spec for my enine in the UK and Australia is 10w40. I'm almost tempted to run a batch of 10w40 and see what happens to my gas mileage, engine operating temp, etc... My guess is i'd only notice that it was a little quieter.
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Originally Posted By: ronrackley
I believe the bad reputation of the 10w40 oils of 30 - 40 years ago is why we have the various 15w40 oils marketed at that weight today - and they are, by and large, excellent oils.
I'd say that the reputation was well earned and that 15w-40 is as good as they can manage in a conventional without issues. The HEDO's of "that era" of 10w-40 were 20w-40 ..straight 40 ..etc..
I believe the bad reputation of the 10w40 oils of 30 - 40 years ago is why we have the various 15w40 oils marketed at that weight today - and they are, by and large, excellent oils.
I'd say that the reputation was well earned and that 15w-40 is as good as they can manage in a conventional without issues. The HEDO's of "that era" of 10w-40 were 20w-40 ..straight 40 ..etc..
Originally Posted By: Alex38
I have about 4 jugs of Syntec 10w40 in my stash, and was wondering which of my vehicles to use it in for a summer oil, and if that was OK. I use synthetic or synthetic blend in my two cars, dino in the truck. From what's listed in my signature, what would you guys recommend? Or should I mix it with some 5w20/5w30 to thin it down a bit?
Syntec 10w40 is somewhat on the thin side for 10w40's at 13.2 @ 100*C. To contrast that, Castrols GTX High Mileage 5w30 is 12.0 @ 100*C, and the 10w40 syntec will be a lot better in the cold.
I would think you could run it in all of your applications, however just be sure to make sure you wont be compromising your new car warranty.
I have about 4 jugs of Syntec 10w40 in my stash, and was wondering which of my vehicles to use it in for a summer oil, and if that was OK. I use synthetic or synthetic blend in my two cars, dino in the truck. From what's listed in my signature, what would you guys recommend? Or should I mix it with some 5w20/5w30 to thin it down a bit?
Syntec 10w40 is somewhat on the thin side for 10w40's at 13.2 @ 100*C. To contrast that, Castrols GTX High Mileage 5w30 is 12.0 @ 100*C, and the 10w40 syntec will be a lot better in the cold.
I would think you could run it in all of your applications, however just be sure to make sure you wont be compromising your new car warranty.
Thank you guys for your replies! It'll be going into the ZR2 this spring!!! Picked the stuff up on clearance at WM, couldn't pass up the deal.
Originally Posted By: jstutz
Sorry hominid7, i didnt see your post before i replied to alex. darn near typed the same thing.
Your memory is spot-on!
I can barely remember what i had for breakfast.
Sorry hominid7, i didnt see your post before i replied to alex. darn near typed the same thing.
Your memory is spot-on!
I can barely remember what i had for breakfast.
well, not really. I just happened to download that data sheet a few weeks ago when AAP had that 25 dollar syntec and filter deal. I was particularly interested in the syntec 10w40 to run in my old suburban that has slightly low oil pressure. Just happens we are talking about the one that i was focused on.
I picked up all of the motorcraft 10w-40 1qts from my Walmart on red clearance the same day I walked away with 4 jugs of edge @15.00 each. I'm in a warmer climate and have no issue using 10w40 in all vehicles at the house.
Those MPG points the car companies got w/CAFE were by getting 0.5 mpg in a 15 mpg truck with a lighter oil and multiplying it by millions produced. When vehicles age and have valve seal issues I was told to stick to 10w-xx and 15w-xx, not concern the second number so much.
Those MPG points the car companies got w/CAFE were by getting 0.5 mpg in a 15 mpg truck with a lighter oil and multiplying it by millions produced. When vehicles age and have valve seal issues I was told to stick to 10w-xx and 15w-xx, not concern the second number so much.
How many new cars/SUV's sold in North America in 2009 recommended xW40 or heavier ? Mostly high performance cars from Europe and some very high performance America cars.
It will be harder to find xW40 or heavier oils in auto parts stores.
It will be harder to find xW40 or heavier oils in auto parts stores.
There will be 5w40 and 15w40 HDEOs easily found for years to come though.
So, just as a for instance, take the Saturn from the OP, take it over to europe and put it on the Autobahn and run it as fast as the traffic would allow.
Would the xxW-30 factory recommended oil hold up to (say) 1000 miles of autobahn speeds?
Would the xxW-30 factory recommended oil hold up to (say) 1000 miles of autobahn speeds?
I use Castrol/Quaker State dino 10w40 in an oil burning/leaking 1999 VW Jetta with the 2.slow engine. I do use 5w30 in the winter. Strangely enough, while I will add over 2 quarts of 5w30 during an oil interval, with the 10w40 I will only add .5 quarts.
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Remember, oils are generically a balancing between HTHS and startup wear. If you were gonna take it over an run it at 1000 mile hot runs at top speeds, too me you wouldn't even risk it, just run a 15w40 or 15w40 and call it a day. I do believe that in that saturn the 10w30 would hold up fine. If the cooling system and all is up to stuff, the engine should only get so hot and lets face it, saturns are not high HP performance machines. Just my thoughts.
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