Hey everyone,
I am running into an odd situation with my 2014 Nissan Maxima. As the hot weather season has begun, my coolant temperature will go up, as high as you to one or two lines below the H line - then back to center, then back up, then back to center, back and forth.

I had replaced the thermostat about 7 months ago and figured it could be some sort of variation due to it not being an OEM part, until this weekend when I took the car on a 50 mile trip, there was a moment where the coolant temp was pinned close to H for a good minute and a half, so I cranked the heat and the coolant temp went back to center.

I ended up taking the car to a shop to have them look at it, and they indicated that the car has a bunch of fault codes for the CVT and that the CVT is overheating, which is causing the coolant temperature to spike. The odd thing is - there's no CEL and the transmission isn't acting odd in any way, shape or form. No odd jolting, no slipping, no power cutout, nothing, it's seemingly functioning as intended. We have changed the CVT fluid and filter every 40K-50K miles.

So my thought is - wouldn't it be possible that something else is at fault that's causing the engine temperature to be higher, which in turn is transferring heat to the CVT, which would account for the fault codes, instead of vise versa? I mean - has anybody ever ran into something like this before?

It was recommended we take the care to a Nissan dealership so they could dive into the transmission issue - but my concern is that there may be a different issue, or that they see the fault codes and instantly say "Yup, it's the transmission!"


Important notes: CVT Fluid and Filter was replaced 3 times since 72K miles (now at 165K) thermostat and coolant, as replaced less than 10,000 miles ago, coolant levels are at their max level, transmission seemingly functioning as intended, no CEL.

 

The cvt has its own cooler, independent of the radiator but it sounds as if you have a possible water oump issue. Heat from the radiator will xfer to the cvt (the cooler is behind the radiator on my 09) but cvt causing hugh wngine temps, well not unless you are turning 3000+ rpm all day due to bad cvt sloppage. My money is on clogged radiator/water pump. Correct that issue and then take a look at cvt.