# What oil do you use? **URL:** \ **Category:** PittSpeed Automotive\ **Created:** [December 2, 2007, 10:20am UTC](https://forums.speedlife.net/t/what-oil-do-you-use/193971 "2007-12-02T10:20:35Z")\ **Posts on this page:** 1\ **Showing post:** 5
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [December 2, 2007, 12:53pm UTC](https://forums.speedlife.net/t/what-oil-do-you-use/193971/5 "2007-12-02T12:53:29Z")
> [@I want to make Tshirts... i need a good blank t shirt](https://forums.speedlife.net/t/i-want-to-make-tshirts-i-need-a-good-blank-t-shirt/33554/25): > > amsoil full synthetic 5w-30 engine oil > amsoil full synthetic synchromesh 5w-30 tranny fluid > > love them both tranny shifted so much nicer and this was changed at about 5k miles on the car > > the valve train on my engine makes less noise now and i HONESTLY get better gas mileage also > > i still change the oil every 5k not like amsoil rec at once a year or 15k miles An old nuclear engineer (a real one) I know out near Philly ran Amsoil in his Stealth Twin Turbo and actually sent his used oil to 2 different labs for analysis after 3 different oil changes (5k, 10k, and one 15k). He was using Amsoil oil filters as well. The results showed that he was basically pissing money away changing it earlier than 15k and last I knew he was going to try 25k mile oil. The drop off in protection between 5k and 15k was, according to him, almost non-existent with Amsoil full synthetic. I’m not at all criticizing you for changing it at 5k, but as much as Amsoil products cost, you might think about sending the oil to a lab (I think he said it actually cost him about the same as a single oil + filter change) to see where you’re at. The results might save you a good bit of money in the long run. --- _[View the full topic](https://forums.speedlife.net/t/what-oil-do-you-use/193971)._