A couple of years ago I bought a lot of 10w30 Trop Artic semi synthetic for a buck a quart from Dollar tree. Since then I bought a Tacoma with the 1GRE V6 engine. I've been running pretty much synthetic because of all those rebates at Oriley's. Well I'm out now because I also change the oil in the wife's FJ Cruiser that has the same engine. I change mom's oil too. So last week I changed the Tacoma's oil and used the 10w30 Trop Artic semi synthetic and a Napa Gold filter. I plan on sending a sample to Blackstone. I think the 1GRE engine is ruff on oil because of the long timing chain. I did a sample runnig about 7500 miles using 5W30 Havoline synthic and the TBN came out to .1(that's right point one). So what do you think, how many miles should I go for the first time on this oil?