It is a little weird leading a transmission upgrade article for our Infiniti G37 with a CSF radiator picture, but stick with us for a couple minutes while we explain. When we first bought our automatic G37 it was a big change from driving manual transmission cars. The 7-speed slushbox designed to handle the daily grind of traffic was great at making gridlock bearable, but that’s all it excelled at. At about 65k miles we did a full transmission flush as part of the Infiniti premium service tier and had high hopes we would feel some improvement in the vagueness of our G37’s shifting. Unfortunately that was not the case. The one good thing that came out of getting the car serviced was that Infiniti provided us a new EX37 as a loaner. It would have been forgettable in every way except that it has the same engine and transmission combination as our project, but yet it shifted so much better! Shifts were quicker, downshifting was immediate and there wasn’t any noticeable lag when applying mid throttle accelerator input. It was clear the only way to remedy our problem was going to be by replacing the transmission.
Today we will be addressing a few additions to our G37 as we prepare for some transmission upgrades. Specifically, cooling and monitoring of our transmission’s temperature. Certainly, these items weren’t on our list when we started our hunt for crisper shifts, but we all know the rabbit holes our projects always tend to lead us through. Fortunately, the network of experts we’ve worked with on this project are sharing their knowledge and expertise to help us avoid calamity ahead of time.
The biggest concern for our car was at times RPM’s would jump up between 2nd and 3rd gear shifts, indicating slipping. The team at UpRev that has been in charge of our G37’s tuning had reached out to inform us that they had made some improvements to their tune since the last time they had worked on our car. So with more horsepower and torque on the shelf we were going to have to address our car’s weak foundation for transmitting that power to the wheels ASAP. Increasing power without addressing our transmission slipping was only going to make things worse.
After talking to Omar at UpRev we decided to go with Level 10’s bulletproof 500hp transmission. It includes new clutches for the transmission, a improved valve body and an upgraded torque converter. UpRev will also be providing a custom transmission tune for it.
Which brings us back to the CSF radiator. Omar at UpRev also recommended changing the radiator to avoid any problems with the new transmission in case the transmission cooler in the radiator was corroding and potentially cross contaminating radiator fluid with transmission fluid. The FSM (Factory Service Manual) procedure for cleaning the trans cooler looked like a real pain and with unknown maintenance prior to ownership, complete replacement was the best option. The Infiniti A/C condenser and radiator are a one-piece unit, so you can imagine what an extreme PITA that makes it to simply upgrade your radiator and not lose your A/C. Thankfully CSF makes an all aluminum performance radiator for our application which comes with a new A/C condenser.