I have 2 Buicks year 2000, one with 77,000 miles and the other with 117,000 miles. We went recently to a different place for an oil change and they persuaded us to use for the first time a synthetic oil on the ground that older cars should use such. Is this true or is it just a way to sell a more expensive oil? If the latter, any harm in my going back to the natural product next time?
No harm, except to your wallet, no harm changing back. No special need to use it in older cars.
They are BS’ing you. Ordinary oil is fine, although synthetic does have advantages. you may switch back with no problems.
Just a way to sell more expensive oil. Your cars don’t need synthetic oil. If they did, it would say so in the owner’s manual.
No harm in going back to conventional oil, although you may be told otherwise (don’t believe it).
Next time you have your oil changed, in either car, insist on the oil specified in the owner’s manual.
Just changing your oil is a job well done ! I also recomend using Lucas oil treatment once a year to help with cold starts. It is a little more money but may help in the long run.
But dont forget your car has been running fine with the over the counter name brand oil, why change a good thing ?
My dad ran a machine shop near Chicago in the 70s. He started asking people what oil they used whenever he did a rebuild. Overwhelmingy, Quaker State left the biggest piles of sludge build up everywhere. I even bought an old Chrysler from a guy that swore he changed the oil at least as often as needed and swore by Quaker State. When I pulled the engine out and took the pan off, it was full of sludge except for a path from from the pan to the sump.
My dad always swore by Castrol. Over the years, he and I probably rebuilt several dozen engines (almost all for ourselves) and put at least 100,000 miles on each one (all Chevy small blocks and Mopar big blocks). I can affirm, when we took any of them down to rebuild again, there was no sludge.
We always used Castrol. And if you know2 anything about mechanics, their vehicles are never maintained as well as they should be. He always shot for 2,500 miles between changes but it usually ended up being closer to 5,000 miles.
Not sure why Rex decided to rant against Quaker State, but just keep in mind that all oils and engines have changed dramatically since the '70s. No oil will create that type of sludge any more.
And the other posters are correct, you are fine with conventional motor oil.
Rex ranted about Quaker State, because it is true. I, too, have talked to other mechanics, and you can always tell when someone used Quaker State oil a lot when the inside of the engine was sludged up badly. No other motor oil did as bad as the Big Q.
He started asking people what oil they used whenever he did a rebuild. Overwhelmingy, Quaker State left the biggest piles of sludge build up everywhere.
That was a huge problem for Quakerstate back then. When cars switched over from leaded to unleaded it drastically raised the operating temperatures of the engines. The Quakerstate formula used then could not handle the increased temps and thus would sludge easily. I was working as a mechanic back in the 70’s while going to college. Many of us saw the same thing. I know one guy who’s car we serviced for a couple years had major sludge in the engine. And we changed that oil every 3k miles with Quakerstate. When we started seeing this and figuring out the answer we too switched to Castrol and NEVER had another problem.
Now in all fairness to Quakerstate…their formula has changed drastically. You can use Quakerstate oil today without any worry.
I didn’t START working as a mechanic until the mid-80’s. This was still the case until at least the mid 90’s when I got a better gig. I’ll never use the Big Q, no matter the claims. Engines are too expensive, and there are too many other better options, like Castrol (personal favorite), Mobil, Valvoline, Shell, etc.
Well there is some benefit. The synthetic oils will provide a little better protection and a little better mileage. That said, I doubt if you are going to reap enough benefit to make the small difference if cost worth it. No harm done other than a little more expensive oil and a little (likely less) benefit.