I just changed my manual transaxle oil the other day and I used Royal Purple Gear Max...WOW this blows mobil one away, I'm getting a big improvment in shift smoothness, I know its getting better protection and its running smoother. I changed my transaxle already a couple years ago with mobil one and it never ran as smooth as it does now.

This all started when I was talking to my buddy that owns a tranny shop and we were BSing and I said I was going to change my trans oil and he ask what kind, after telling him mobil one he said that on a machine he has to measure the friction protection of oils that mobil one ranked dead last agains Schaeffer's, Royal Purple, and AmsOil. Do some research of your own and look these oils up, Schaeffers rocks too I run it in my Camaro.

I just wanted to share this Knowledge with you all because I want you to experience this also. If anyone trash talks this go do it for yourself you won't regret it!

 

how is this not work safe

 

wondering same thing here

 

It might not be smooth for long...

RP Max Gear is NOT designed for these transmissions. It contains friction modifiers which will eventually kill the F35...

 

its fine in the F35, gear max is made for GL5 trans.

 

we have conflicting opinions here, we need TRUTH people....

 

I have research and proof from testing on my side, beileve what you want. Chevy most likely made a deal with mobil 1 and got paid for it thats why they recommend Mobil 1. I'll stick with Royal Purple MAX GEAR OIL 75W90

 

i was expecting a girl sitting on a shifter or something like that damn. got my hopes up lol

 

yeai actually was too at first lol

 

you can run rp in your car so as long as you get straight weight fluid. honestly to me I rather just run oem fluid cause it doesnt change at all. when i ran rp I would notice when the fluid would start to break down and need changing.

 

the OEM transmission fluid isnt mobil, its a castrol BOT XXXX fluid (i cant remember the number). its specificly designed for the f35.

oem stuff is the best you can put in it.

 

I was thinkin the same thing

 

GM recommends NEITHER RP Max Gear or Mobil 1 gear oils, both contain friction modifiers which will damage the transmission.

They recommend to ONLY fill with Castrol BOT 0063 from the dealer, for good reason too.

You say you've done research, then I assume you know what modifiers do to the syncros and blocker rings in this trans...

 

NWS! icon removed.

 

Hmmm... Interesting because I have been RP Max Gear for quite some time now and it works phenominally in there. No damage to the tranny and I have been running it for well over a year now.

 

Saying that RP will damage the tranny is like saying that if you don't run mobil 1 in your engine it will blow up.

 

I'm running RP ATF fluid, thats what RP recommended as a replacement for my Getrag.

 

fill with what yo wish, I'm jst trying to save a few headaches down the road...yes the F35 takes a GL5 flid, a NON-FRICTION MODIFIED one...

 

Different tranny but I had RP Synromax in my 2.4 manual for just over 2 years before I traded it. No problems.

 

the f23 in the 2.2/2.4 takes ATF (dexron 3 or 6 depending on the year) and syncromax is designed as a replacment for thinner fluids in manual transmissions, like gm syncromesh or atf.

i guess a basic rundown on friction modified gear oil is in order. basicly, friction modifier, also known as limited slip additive, was designed for clutch style limited slip diffs. what happens in a clutch style limited slip is when turning a corner the clutches in the differential must slip in order for the wheels to turn at different speeds. gear oil is stickey to a point, and what ends up happening is the clutches slip then grad, slip and grab, creating a chattering or shuddering feeling. in order to overcome this, friction modifier is used to make the oil more slick so the clutches can slip without chattering.

now in a manual transmission, your syncronizers, or blocking rings need friction. when you shift gears the shift sleeve presses the syncro presses against the gear, and this matches the speed of the output shaft to ensure a smooth, grind free shift. if you start adding friction modifiers that make the oil more slick, the syncros can start to slip on the gear, eventualy wearing the syncros down and you will start having it grind when shifting.

 

nice write up. thx

 

^^^ X2! Sharkey knows his ****!

 

I have an LSD so whats the problem?

 

the lsd in our cars is not a clutch style, its a torsen or worm gear style. there are no clutches in it, it doesnt use friction modifier

 

You *CANNOT* use friction modified fluid in the F35, it will damage the gears and bearings. You should only use the GM fluid (which is the Castrol BOT0063 fully synthetic 75W-90) as it is the only fluid that noone has had any problems using. If you want to risk using any other synthetic 75W-90 that is your choice but DO NOT use any friction modified gear oil! Saab specifically states the MTF 0063 cannot be mixed with any other MTF or bearing and gear wear will occur.