My suggestion would be to put a gauge in there & see where YOUR temp is at for a baseline then decide if it's needs changing. I've read the posts about using the bottom stock cooler in series to warm the fluid but after reading about some of them developing leaks & contaminating the trans w antifreeze I've always preferred to bypass it & use only a large aftermarket flat cooler that comes w the (4) black plastic rods & no problems to date. that & I would not jump on the eng until it (& the trans) are warmed up.