Originally Posted by 1turbofocus
Ford chooses the fluids for the MTX for what FORD plans the use of the car to be used for over the life of the car , when you change a car from its intent of getting you to work and for groceries to a performance car you then have to make other changes as well , engine oils and trans fluid is one of those changes
Change your fluids regular and it wont matter much what you put in there , they all will work , like stated I use mobile engine oil in the MTX-75 and the Getreg , I have never seen any improvement using the redline or RP lines of fluids and I am around some major teams that also have done testing and they dont use them either
To say a trans will go bad if you dont use the fluids ford says is silly as the car isnt being used for what Ford expected it to be used for
No way, it is not silly to state that certain fluids are not compatible. That is an ignorance-based position that will cause harm to member's hardware. This I know after working in the petroleum industry and rebuilding manual transmissions for 35 years. There are fewer than five 6spd getrag BMW M3/M5/540i tranny rebuilders in the USA and I'm one of them. The additives in GL5 hypoid gear fluids eat modern yellow metal, sintered or carbon-wrap synchros widely used since the early 80's. You can change the fluid daily and the chemistry will still be wrong. If you get 5 years out of the tranny you'll be lucky. This reminds me of my buddy who used gear lube in his beautiful $6K Husaberg one summer and it ate the nikasil bore coating. The drain pan looked like aluminum paint. Being around a race team does not make anyone a transmission or lubricity expert. All it does is coerse people into falsely assuming that race fluids are better or even OK for street. Redline is not approved for use in ANY street car, period. It is a competition fluid for competitors who are willing to wear out and rebuild their hardware on a seasonal or frequent regular basis simply to achieve fractional horsepower gains. I'm not going to rebuild my street car more often just to gain a couple HP or less. If you want your motor or tranny to last more than 10K miles, choose recommended fluids with proper certifications, ratings and formula. The factory fluid is $20/qt for a reason. The MTX-75 will easily last 300K mi with the proper lubricant and changes once every 100K mi. With the GL5 hypoid stuff the synchros will disintegrate until clearances exceed spec and it chronically grinds. My MTX-75 will never need rebuilt because I run the appropriate lubes. The chassis will rust away first. I've rebuilt over 20 track trannys and I know what the wrong lubes will do. The Supra, Mustang and BMW communities learned this long ago.