Aight Guys, Im new here so give me a break lol. Regardless, I bought a 2005 Ford Ranger XL 2.3l 4cyl back in 2007 at 85000 miles. I change the oil every 3000-3500 miles. The first 4 were free at the local Autoway Ford since I bought it there. I figure they were used with Motorcraft oils. Then after that I took it to my mothers mechanic who uses Napa Gold Filters and Kendall Dino. after about 2 oil changes there I started doing it myself, using a Purolator Classic or a Bosch Black filter and Quaker State High Mileage. Last weekend it seemed like everyone around was out of QS High Milege so I switched it up to Pennzoil HM and when I bought that the store I bought it from had a deal buy any Pennzoil/QS product get 2 dollars off a filter, so I upped my filter to a Purolator Pure One. Now my truck is running kinda odd, pressing down on the accelerator It seems to take longer to get up to speed and the truck is kinda shakey accelerating. No noises and no odd smells and it doesnt seem to be burning anything. Regardless, when I bought the truck it specifies 5w-20, when I got my changes at Ford they put in 10w-30, my mother mechanic put in 10w30, so naturally I put in 10w-30... Could this be the problem? Should I switch back to QS HM 10w30 asap? or wait? its not uber bad. just different to me. Im thinking next change to go to a Synthetic anyway. at 120,000 miles will this be bad? I havent had any other problems with my truck since ive gotten it other than a bad coil pack. Not bad for 35000 miles. Thanks!