Hey all -

Welp, title says it all. My G has 80k on it (my dad bought it new) and Ive had it about 6 months. Started shifting hard and pissed out SMOD out of coolant resevoir. Drained trans and had it there too. Doing a trans replacement myself with a JY trans with 68k on it since my local shops wanted $5600 to do it.

Long story short, I want to bypass trans oil cooler in rad for an aftermarket trans cooler. Is the B&M the way to go? Read alot about the trans cooler in the rad doing as much work to warm the fluid as it does to cool.

Just dont want to do all this work (those Demon bolts were fun) and screw up the replacement trans by not allowing it to get "warm" enough especially since I only drive it 10-15 miles daily.

Thanks!

You're not going to hurt the 5AT by running it cold unless you're talking fluid temp below zero. In that case you should warm up the engine fully before driving. Much of the heat from the engine block ends up soaking into the transmission anyways simply because they're mated together.

As for aftermarket trans coolers, I don't have much experience with them on these cars, nearly every G I've worked on was a 6MT. Should be plenty of aftermarket options though so look at what's available for the SIZE of cooler they use

Most modern transmissions have a flow control valve in them to restrict fluid flow through the cooler lines when it's cold. Also, it's a pretty significant amount of heat generated from a transmission/engine combination. Even in REALLY REALLY cold environments with things like heavy duty trucks that have massive external transmission coolers it's not an issue. Warm up the engine before driving during the winter.

Also I know for fact these transmissions use temperature sensors to control line pressure. They already have compensation measures to control internal stuff due to temperature variation.

I don't recall this occurring very often on the V36 anyway... now Nissan Frontiers back in the day yes...