gamma113

Hi all,

I currently own a 2014 RWD IS350 F-Sport. I have been told by my local Lexus Dealership that I should upgrade my rear differential oil to Red line heavy shockproof Gear oil (Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90) since I do drive my car aggressively from time to time and I take it to the track two times a year. I am confused as which differential oil I should replace it with? Has anyone got experience with Red line heavy shockproof Gear oil for their 3IS?

swaangin

strange, i would just tell them to use the OEM oil that the car came with.. maybe they told you that because you said you drive it hard / track it? probably trying to upcharge you for some oil.. i just had mine done at 40K miles with transmission fluid change

E46CT

Redline synthetic will always outperform its equivalent spec mobil 1/valvoline etc. however for street driving and occasional high performance driving, they'd both be the same. i mean you can get a used diff online for like $200 so honestly spending $300 in fluids over the course of your ownership to save a $200 item really isn't all that prudent. i'd just go with the normal fluid if it were me. use whatever viscosity the manual specs. what is it 75-140? 75-90? go look it up

the drive line on my 97 M3 (a few years ago) was crisp and buttery smooth as ever with original fluid in transmission AND diff at 205k miles. no noises, no grinding. nothing. functioned perfectly. car was tracked, drifted, and even off roaded (lol). i changed the fluids for good measure though, came out black.

you'd be surprised how long old driveline components can run on original fluid.