Will manual tranny start leaking if I switch to redline?

[Uncle Paully]

hey guys

i wanted to take a quick poll on personal experience about the tranny starting to leak if i start using redline synthetic (D4 ATF) in my manual. the trany has almost 40k miles on it and is currently not dripping oil.

[Rory]

hey guys

i wanted to take a quick poll on personal experience about the tranny starting to leak if i start using redline synthetic (D4 ATF) in my manual. the trany has almost 40k miles on it and is currently not dripping oil.

Not likely. Synthetics do not create leaks regardless of where they are used. If you have a leak that is being blocked by sludge for example, the extra detergents of a synthetic may clean out the sludge and you will start dripping. But they will not start a leak. Synthetics are a no brainer for me. Redline D4-ATF in a BMW manual is very solid. My 5 shifts the same at -5 or 90...YMMV.

Best,
Rory