I recently supercharged my g37x(7 speed auto) with the stillen kit and my transmission starting slipping real bad on the dyno(58k on the transmission). now i'm on the hunt for a new transmission. I looked into building it with level 10 but i saw a lot of bad google reviews. Anyone build their transmission through them? also, let me know if you know of other companies that builds them. the best thing to do is to obviously build it but i'm wondering if i get a used one with low mileage, is doing the valve body upgrade enough for the transmission to hold the power?

 

Just curious how recent is the SC was the line pressure adjusted with the tune? If not the trans will slip and feel like it's no good. I know I had zero issue with my trans. Level 10 is the way to go"if" you really need one.
BTW I hope you have a trans cooler installed cause it is a MUST with the SC

 

i did have a trans cooler installed. I'm not sure if they adjusted the line pressure. i was pretty upset when it broke on the dyno so i didn't really leave on a good note. I really don't wanna spend the money on a built transmission if i don't have to. did you do the valve body upgrade?

 

I didn't. It didn't need it was shift very good. Did it blown on the dyno when tuning. if it wasn't adjust not sure what kinda a tuner he/she is? That's the first thing they do. Sorry man :/

 

and this is why i will never boost this car... it doesn't matter if it broke on the dyno or street the auto transmission is weak with boost.. some hold up longer than other's..but to be mad at the place that had the car is the dyno is just wrong..the transmission had a issue before its obvious!
this is why if you are going to play with boost you should do it right and build everything..
you can always buy the parts from them and have someone else build it..
my bad stupid link was for a 300zx not g37..

 

I got the valve body and torque converter done by Level Ten, but a bit after my supercharger was installed. I didn't have any issues before, but I did notice smoother/faster shifting after the transmission work. I'm going to assume your tuner messed up the line pressure as well. Either that or you just very unlucky. :/

 

Level 10 did my 7AT and it is amazing, but if the tune is not correct (line pressure/shift points) the added power will still destroy it.

 

Was not blaming anyone was just curious if the tuner adjusted the line pressure,

Agree with you, BTW was just asking. Fi stock trans wiil break some day is 100% correct but if he just installed it something else was wrong. An no the tuner would be paying for the trans either.

 

My trans was fine before it ever got on the dyno. I wouldn't have supercharged it if i knew there was something wrong with it. there were some small issues that were addressed before it got on the dyno that i paid for them to correct. I wasn't going to blame them if it weren't for how they acted. the transmission started slipping on the dyno and the tuner signaled the front desk salesmen to come into the garage and talked to him for a few mins and the salesman came back to the front and told me everything was good to go and asked me to pay. He should have immediately told me that the transmission was slipping. I had to ask the tuner how it drove when he took it around the block for him to tell me what was wrong with it. Again, it could just be my bad luck and i would have accepted that if they weren't sneaky about the whole situation.

 

Probably it has something to do with the mileage (58k miles) on the transmission and the tranny fluid fill as well, sounds like the sc instantly broke the tranny. My tranny is only at 26k (kms) with cooler and tune, seems to be fine for now. I think Z1 is developing a 7AT clutch pack kit, maybe give them a call.

 

I did my supercharger at around 50k miles and I'm running strong still.