With conventional oil I'd say 3000 mile if you put a synthetic 5w-30 I'd say 5-6000 synthetic is more forgiving and holds up better. But the first oil change that you put synthetic I would go 4000 and change and then go to 5-6000.
The interval for conventional is 5000 miles as recommended by Toyota. Any less and you are wasting money. Synthetic is the way to go without a doubt. Don't believe any of the hillbilly myths about synthetic. Chances are you were noticing another problem. If synthetic was damaging engines then these big companies would be in some big trouble.
If you want MORE miles from the engine.... keep it like new and do frequent oil changes like 3000 miles. If you buy oil (5qt, Valvoline synthetic blend, $17) from Walmart and OEM filter ($4), you basically will spend about $23.
Problem with synthetic is the filter. It is not designed to fun for 6000 or so miles (correct me if I am wrong). And how much you pay for this? $35 with the filter?
Napa gold filters can withstand 5-6000 miles with synthetic. The oem toyota filters are crap in my opinion. If you cut napa gold and oem filter inhalf and do a side by side you will see what I'm talking about. I'm not a fan of oem stuff honestly. For the price of what you get it's honestly not worth it. The only time I got to the dealer is for stuff that I can't get anywhere else. And honestly I'm not opposed to going 5000 miles with conventional I just think that it just leaves that much more time for it to break down and not do it job.
I know I feel like I'm the odd one out. Most people on here swear by oem stuff but growing up around a shop you learn fast what's worth it and what's not. And dealer filters and most stuff Is not worth it IMO I'm not trying to upset any one this is my opinion and I'm open to listening to what people say. It's possible toyota has upped quality on the filters but 2 years ago I split one and it wasn't the best. Not the worst but not the best.
The interval for conventional is 5000 miles as recommended by Toyota. Any less and you are wasting money.
Changing more often than Toyota recommends might also increase the rate of metal wear.
Used Oil Analysis: How to decide what is normal - Bob is the Oil Guy
I know I feel like I'm the odd one out. Most people on here swear by oem stuff but growing up around a shop you learn fast what's worth it and what's not. And dealer filters and most stuff Is not worth it IMO I'm not trying to upset any one this is my opinion and I'm open to listening to what people say. It's possible toyota has upped quality on the filters but 2 years ago I split one and it wasn't the best. Not the worst but not the best.