# I have mixed oil types in my car. Is that a problem? **URL:** \ **Category:** Factual Questions\ **Created:** [July 20, 2025, 5:10pm UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119 "2025-07-20T17:10:17Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [July 22, 2025, 2:30am UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/21 "2025-07-22T02:30:45Z")
> [@Tired\_and\_Cranky](#): > > I race what are basically junk cars in endurance racing. I an always amazed at the breadth of experience and expertise on the Dope. 😎 ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [July 22, 2025, 8:53am UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/22 "2025-07-22T08:53:33Z")
> [@Tired\_and\_Cranky](#): > > incredibly thick gear oil Note: gear oils are measured on a different scale. The numbers are not directly comparable. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [July 22, 2025, 4:40pm UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/23 "2025-07-22T16:40:01Z")
> [@Tired\_and\_Cranky](#): > > I race what are basically junk cars in endurance racing. The 24 Hours of Lemons, I presume? ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [July 26, 2025, 7:56pm UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/24 "2025-07-26T19:56:29Z")
Took the car to the Great Canadian Oilchange, one of those in-and-out oil change places, and had the oil completely replaced. Now just 0W20, no mixture. Also got air filter, rear window wiper, and a burnt out reverse light replaced. Done in 20 minutes. ---
**Author:** ![DaveUnknown](https://avatars.discourse-cdn.com/v4/letter/d/94ad74/32.png) [@DaveUnknown](https://boards.straightdope.com/u/DaveUnknown)\ **Post date:** [July 27, 2025, 3:06am UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/25 "2025-07-27T03:06:15Z")
> [@WildaBeast](#): > > The 24 Hours of Lemons, I presume? Haha, is that a real thing? I hope it is, Im not going to look it up because I want it to be a real thing. Thats the kind of pun to build an event around, yes. ---
**Author:** ![scabpicker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scabpicker/32/8268_2.png) [@scabpicker](https://boards.straightdope.com/u/scabpicker)\ **Post date:** [July 27, 2025, 3:27am UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/26 "2025-07-27T03:27:59Z")
Oh, totally real. My favorite tagline for it is: Nasty Brutish Not Short Enough [![](https://img.youtube.com/vi/LHwXtQz_qxY/maxresdefault.jpg "What is The 24 Hours of Lemons?") ](https://www.youtube.com/watch?v=LHwXtQz_qxY) > **[24 Hours of Lemons - Wheel to Wheel Racing for $500 Cars](https://24hoursoflemons.com/)** > > Because racing isn't just for rich idiots... it's for all idiots. ---
**Author:** ![Tired\_and\_Cranky](https://avatars.discourse-cdn.com/v4/letter/t/a87d85/32.png) [@Tired\_and\_Cranky](https://boards.straightdope.com/u/Tired_and_Cranky)\ **Post date:** [July 27, 2025, 11:02pm UTC](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119/27 "2025-07-27T23:02:26Z")
> [@Melbourne](#): > > Note: gear oils are measured on a different scale. The numbers are not directly comparable. True, and I didn’t say or suggest otherwise. > [@WildaBeast](#): > > The 24 Hours of Lemons, I presume? Yes. I can neither confirm nor deny that me and the car I race are featured in the video to which @scabpicker linked. [Previous page](https://boards.straightdope.com/t/i-have-mixed-oil-types-in-my-car-is-that-a-problem/1021119.md?page=1)