# what oil is best? **URL:** \ **Category:** SON240sx Automotive\ **Created:** [March 12, 2004, 2:03pm UTC](https://forums.speedlife.net/t/what-oil-is-best/80701 "2004-03-12T14:03:44Z")\ **Posts on this page:** 6\ **Page:** 3
**Author:** ![DarkForceJackal](https://avatars.discourse-cdn.com/v4/letter/d/b38774/32.png) [@DarkForceJackal](https://forums.speedlife.net/u/DarkForceJackal)\ **Post date:** [November 27, 2004, 10:21am UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/41 "2004-11-27T10:21:18Z")
Back to life comes this thread! :batman: Anyway…can you safely run Redline MT90 75W90 (GL-4) in our R200V diffs? Because the FSM states otherwise (GL-5 required), and so does the Redline product (“Not designed for use in RWD diffs requiring GL-5…”) ![http://forums.son240sx.ca/album_pic.php?pic_id=584](http://forums.son240sx.ca/album_pic.php?pic_id=584) So, does any of it matter? Does it work fine & be done with it or is it a bad idea or maybe a better product to recommend? ---
**Author:** ![DTS](https://avatars.discourse-cdn.com/v4/letter/d/8491ac/32.png) [@DTS](https://forums.speedlife.net/u/DTS)\ **Post date:** [November 27, 2004, 11:52am UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/42 "2004-11-27T11:52:22Z")
10W 30 in the SR Mobil 1 only oil i will use other than royal purple in the 929 Valvoline high mileage, shit really works. DO NOT USE LUCAS ATF ADDITIVE I HAD A PEREFECTLY GOOD TRANNY AND A DAY LATER IT COMPLEATLY STOPED WORKING i will never ever use lucas again. i added the lucas atf additive and it over swelled the seals and now R and D are like neutral horrible shit. ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex034/uploads/speedlife/original/2X/b/b7170c8eddc0b95ece6b88172b2f416a08489a45.png) [@system](https://forums.speedlife.net/u/system)\ **Post date:** [November 27, 2004, 3:40pm UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/43 "2004-11-27T15:40:49Z")
> [@DarkForceJackal](#): > > Back to life comes this thread! :batman: > > Anyway…can you safely run Redline MT90 75W90 (GL-4) in our R200V diffs? Because the FSM states otherwise (GL-5 required), and so does the Redline product (“Not designed for use in RWD diffs requiring GL-5…”) > > So, does any of it matter? Does it work fine & be done with it or is it a bad idea or maybe a better product to recommend? I work at a lube shop, And i’d definately not put in any GL-4 grade oil in your diff. My suggestion for the o.e.m diff, dont waste your money and use redline/royal purple or any high grade stuff. its not worth it. PM me, I can hook you up at my work if you’d like… Regular Castrol GL-5 Gear Oil Diff Change is $39.99 Syntec Castrol Oil Diff Change is $99.99 We also have Quaker State and O.E.M gear oil’s… Well hope that helps… If you come to my work ill give ya 10% off regular GL-5. And 15% off Syntec Oil’s. ---
**Author:** ![DarkForceJackal](https://avatars.discourse-cdn.com/v4/letter/d/b38774/32.png) [@DarkForceJackal](https://forums.speedlife.net/u/DarkForceJackal)\ **Post date:** [November 27, 2004, 4:19pm UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/44 "2004-11-27T16:19:55Z")
^^^ Thanks man. However, I was offered $79.99 at a local Mr. Lube for Mobil 1 Synthetic Diff oil when I told them I had a 240 (didn’t know Mobil made it…I guess it would be GL-5…?) Does that sound right/good IYO? Have you heard of the stuff at your location etc (assuming I want to go synthetic)? ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex034/uploads/speedlife/original/2X/b/b7170c8eddc0b95ece6b88172b2f416a08489a45.png) [@system](https://forums.speedlife.net/u/system)\ **Post date:** [November 27, 2004, 10:15pm UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/45 "2004-11-27T22:15:10Z")
If your going Synthetic at a Mr.Lube, The best stuff is the Syntec/Mobil 1 for 240’s ---
**Author:** ![DarkForceJackal](https://avatars.discourse-cdn.com/v4/letter/d/b38774/32.png) [@DarkForceJackal](https://forums.speedlife.net/u/DarkForceJackal)\ **Post date:** [November 28, 2004, 12:25pm UTC](https://forums.speedlife.net/t/what-oil-is-best/80701/46 "2004-11-28T12:25:20Z")
^^^ Just did it for $79.99 at Mr. Lube, went from black crap to Mobil 1 synthetic “honey”. Yummy. 8) [Previous page](https://forums.speedlife.net/t/what-oil-is-best/80701.md?page=2)