I've generally heard that time based oil changes aren't needed for "modern" oils. One just needs to go by the number miles. I'm not sure if "modern" is referring to synthetic oils or all current day oils though.

I believe there is conventional oil in it, which I plan on continuing to use. What is the wisdom with conventional oil?

I'm asking because I bought a 1988 Carrera recently. The last oil change was May 2024 but it was only 1,000 miles ago. I checked the oil today and the oil on the dipstick looks new. I'm trying to decide if I should change the oil before I put it away for the winter. It's been 5-8k miles since it's last valve adjustment in 2019, so if I wait another 4k miles I can just get the oil changed with the next valve adjustment.

I feel like driving it until it is hot so there is no moisture in the oil is all that is needed before I store it for winter but maybe I should change it.

 

Well, even new Porsches using synthetic oil have a 12 month oil change interval. But is it really needed? I think it would depend on how it is driven.

For you, I would change it just because you don't know what is in it now. What weight, what brand? You don't know what to buy to top it up. You're not even positive if you have synthetic or not.

Then make the call next year depending on how you drive it. If you always drive longish trips, you could probably get away with going another year.

Most of us would change before putting the car away for the winter. Even after a low mileage year, the hot oil will still smell of combustion by-products that I wouldn't want sitting there for months.

It also sounds like you would like to push this oil to 5,000 miles. I would only consider that if you drove mostly highway within a 12 month period. If you are mostly around town, I'd change the oil every 3K-4K miles.

Mark

 

You raise a good point on not knowing how it was driven. I will change it before I put it away this year.

 

Look at your oil after 5k miles and it will be black

 

don't overthink it , oil is cheap . just recycle it properly.

 

I disagree with much of what is said in this thread. What is the evidence that "combustion by-products" in newish oil can damage an engine? With only 1000 miles since the last oil change 5 months ago, it certainly won't hurt to change the oil before putting the car away for a few months, but likewise it won't hurt to wait to change it until next spring. And with only 1000 miles on it, I probably wouldn't even change it then.

 

Why would you then ever change the oil?

With an old more or less worn engine with old, not very precise fuel supply, it’s a good idea to change the oil before store the car. This way the fresh oil with neutralizing additives have better change to cope with combustion by-products.
And do not start the engine for short times when car is stored.

 

Agreed. If OP decided to not change I'd just go get in nice and hot to evaporate any condensation and then park it.

 

It's hard to answer these kinds of questions without introducing your own biases and neuroses. I bought my SC in NJ. My Dad and I drove down, then drove back the same day. I remember being so anxious because I had no idea what oil was in it, or how old it was (no records). Felt way better after I changed it.

I guess that's why I told Nathan to change what he has now - why take a chance, especially if he's going to push the oil changes to more than annual. Yeah, I know that annual changes are probably not really needed. I still like to do them.

Mark