SirKeats, pretty much.
The manufacturers each have their own comfort level as to how far out of factory spec they are willing to go. Red Line, Amsoil, RP and others do this as a way of expanding the potential customer base. I look at their recommendations and try to double-check
I am going to try Amsoil MTF for my '06 Civic's 5-speed manual tranny. Amsoil claims it is a direct replacement for Honda MTF (I & II) ... but I thought Honda MTF was 10-11.5 cST ... and the Amsoil is 9.6 cSt. I just can't confirm the Honda spec ANYWHERE. If the Amsoil doesn't seem right, I'll dump it in a year and go back to genuine Honda MTF.
While I've seen some people have good results with RP products, in my opinion they are short on engineering/innovation and long on bling-bling. If your tranny called for ATF, I'd say go ahead and buy the Synchromax as it is the only true synchromesh gear oil in that super-light weight now that Specialty Formulations has closed its doors.
However, if yours asks for GM-brand synchromesh, I'd try one of the several fluids available in the correct thickness. This is a popular weight and you have plenty of appropriate choices.
Remember, I'm using actual weight numbers ... not vague, brand-specific puffery.
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--- Bror Jace
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