Redline MT-90 vs MT-85

I have a 2015 TRD Sport with 6MT <6K miles and TRD Quick Shifter. I wanted to change out the transmission oil to Redline MT-90 75W90 GL-4 and ordered some thru Amazon. What I received was MT-85, 75W85 GL-4.

Should I return it for MT -90 or .... use it?

 

Thread revival! Did you ever use the MT-85. I am thinking about trying it next.

 

Curious as to why? The MT90 is tried and true, so why stray from the known?

 

I have an aging 06 with weak ass brass synchros. The MT 85 is newer. I think a thinner fluid would help a bit...plus my wheeling buddy said he saw an improvement when he went from 90 to 85.

 

I think newer 6-speed Toyotas use 85W-90, at least 2010+ FJ.

I have used Redline MT85 in my 07 FJ gearbox for years, works perfectly.

 

Thanks FinnJ, good to know, I am gonna try MT85 and see if it's any improvement in synchros. Currently running MT90 with decent results except when cold and in a rush 3rd gear grinds.

 

SAME HERE! Curious on your results.

 

Late reply but I do not recommend 75w85. Spec is 75W90 and the reason why is because you need to a thicker/less slippery oil for synchros to function properly. The oil allows the synchro to grab the cone without slipping excessivley.