hi Scotty,
can I use synthetic motor oil in my 05 xb. My mechanic brother said I shouldn't because my car is too old and suggest I use high mileage oil. My car has 204k miles and I change the oil every 3500-4000 miles religiously, by myself (I'm female) but a car fanatic.
nora
Yes. Use regular synthetic.
What happens is that sometimes engine sludge is what's keeping an engine from leaking oil, if you switch to synthetic it can clean out that sludge and make leaks appear that were there before, but you didn't notice because of the internal buildup.
I've switched back and forth between synthetic and conventional with no issues.
If your engine has been well taken care of and had regular oil changes, you probably won't run into any issues but it IS possible.
@rpmartin32
That makes sense. I'll stick with conventional oil. Thanks to the both of you. My brother is too impatient to explain stuff like this. I like to get under his collar by saying "but Scotty says..." Or "the manual says to do it this way..."
I would also recommend a high mileage oil. You likely wouldn't see any benefit from switching to synthetic.
@cjbman
Like Scotty I'm cheap also. Costco has two 1 gallon jugs of full synthetic oil for $27. Walmart has their brand of conventional oil one gallon for $16. My brother says something about gaskets being too old and the synthetic would cause leaking. What's so good about high mileage oil anyway?
High mileage has more detergent and additives like zinc to keep the engine from creating oil deposits and preventing wear from age.