Also has any one here done it on a 07 6mt if so how do you like it is it noticeable?

 

God damn 3.9 is harder to get and more expensive than the 4.08...WTF?

Like stated earlier, i dont wanna go higher than 3.9 because its an auto.

Anyone (autos) running the combo of Transgo kit and 3.9's?

And is this mod just as good for the DE as it is for the HR??

 

+1... interested to know the same..

 

I just purchased the 4.08 gears ring and pinion and having them installed next week on my 5at Z!!!! I cant waitttt!!!

 

I have the Transgo installed, as soon as i have th gears running i will have my input on them guys!

 

Hey man can you share your thoughts on the gear upgrade, especially with the transgo kit installed. How is it performance wise? How is it on the streets every day?

 

Yes, well having these two upgrades on the car feels totally different than a stock auto. The Transgo kit shifts like a shotgun when put into manual and rides stock when in D mode. It does tend to jerk a bit but nothing serious this is a must for Auto guys, as far as the gears....they are amazing!! I really can't agree with you guys on the opinion of them on a Auto Z. Yes, they are blazing quick, yes the eat up more gas(if your a dog with the shifting) yes, they are streetable even in D mode, and yes its a bit noisier with the driveshaft. They only thing I noticed when driving is the spinning of the driveshaft it only a bit louder but other than that, these 2 mods a highly recommend.

 

I have a 2003 350z 5at and I installed 3.7 gears from a 2008 g35 sedan sport 6mt. I also have the transgo shift kit. i will have to comment that the z feels slower now on the highway but punchier in the streets. sadly i did the head to head run against others and truth be told shorter gears pulls harder from the start but the moment you get to highway speeds all i saw were tail lights. 1st and 2nd are punchy, but they also feel slower because they don't stay in the power band long enough. 3rd and 4th feel great and they are the only gears that actually feel powerful now. Its as if i traded my 1st/2nd for 3rd/4th power.

I will try out the 3.5 gearing on my 5at and comment about that. i can't imagine 3.9 and 4.08 being enjoyable on the freeway.

my cruise control works fine and was tested up to 80mph, however, at 80, the car is only moving 75mph. the speedometer is now off 5mph on the freeway.


my traction control flashes slip with 3.7 gears:

1.) during turns where i gas it in full auto mode
2.) during the rain in 5th if is make sudden side to side lane changes
3.) randomly during hard cornering while throttling out of the turn in tiptronic mode

it stays in slip mode up to 20 seconds if i do not let off the gas regardless if i'm in a straight line, this did not occur ever in my 3.3 gears. i must let off th gas UNTIL the slip light turns off or else it just stays in slip mode.

 

Anyone else getting a slip light with gears?

 

no one should, pulled my diff a few hours ago 3.7 time.

 

I should mention that I'm running a square setup of 265/40/18 all around. front tires are bald from canyon runs, rear tires are nearly new. If i'm correct, staggered setups with taller rear tires will not have slip light issues (or at least much less) on 3.7 FD gears on a 5mt.

 

Square pattern is Square pattern, gear ratio doesn't matter. The slip lights get their info off the wheel speed sensor, and FYI speedo is off the rear wheels.

 

slip light gets their info from all 4 wheel sensors. the abs sensors from all 4 wheels function also to determine if the any of the rear wheels are rotation faster than any of the front wheels. every time the spline of ring passes the magnetic it pulses. if you ever digitally plug into the wiring you'll see during driving that the vss readings are in thousands (pulses) and in idle speeds on a lift it pulses less than 100 for the rotating wheels. however, factors that are also calculated is the speed of the car during the changes of wheel rotation speeds (measurements of pulses). what i didn't expect was that the ecu seems to also monitor the engines rpm against the rear wheels rotation and what gear it's in. simply put theres more variables as to when and why the slip occurs for me and others that have changed rear ends.


After further time testing different wheels to figure out the slip, I will have to add more facts about slip light issue. I'm sure newer z's the ecu must be programmed differently, but for 2003 touring 5at, the following gives slip with 3.7 gears:

square setup (non staggered wheels, 265/40/18 tires all around):
1. while driving straight, ANY autocross like side to side motion while on the gas past ~25mph+ causes slip

2. any hard turns at speeds around ~25mph+ while still on the gas pedal causes slip (example: exiting the freeway at high speeds or entering freeway junctions at high speeds)

3. if you trigger slip, and hold the gas, and and repeat what you did to trigger it in the first place; it keeps the car in slip for a long while as you keep on the gas pedal. (still on gas pedal) the car will slowly decelerate in gear then very slowly unslip. HOWEVER, if during the deceleration the car up shifts to the lower gear, it triggers slip again and car will deceleration down to around 25mph. i did this several times to be certain that i wasn't being mind f*cked. you have to imagine how annoying it is when you slip at high speeds and hold the gas and the car slows to around 25 on the freeway. i did this during the night many times including mashing the pedal to the floor hoping for the annoyance to stop....


staggered setup with taller rear tires (245/35/19 fronts, 275/35/19 rears):

what slip.... oh wait it showed slip when i actually broke the tires loose during the turn.


so for all you readers, thats the low down experience of a 2003 touring model, 5at, transgo shift kitted, 265/40/18 square setup, 3.7 final drive gears with vlsd. i've had this setup for about 3 months now so theres no arguing with me about slip if you have the same exact year/model/setup as i do.

I'm going to end up posting the 3.7 diff in the classifieds soon. 3.5 will be more of the medium i'm looking for.

 

I have a 2005 with AT and transgo shift kit with stock gears. I track the car occasionally (couple times a year) and it is generally my weekend driver. Even after osirus, the car lays down a bit in third even with cams, headers, etc. I want to go to the 3.7 gears with a Nismo LSD. I found out after I bought the Nismo LSD I need a MT rear for it to work or at least chane to MT ring and pinion. So I have a couple questions-

Can you cruise pretty well at highway speeds say 70 mph?
Ever try turing the TCS OFF to eleminate the slip light? Obvious solution and on then track, that's what you do anyway.
How much do you want for the set up and where are you ?-PM may be better.
Does anyone know a Nissan part number for a 3.7 ring and pinion set up? I can find on Z1 but it gives their part number.

 

cruising at 70 is fine, luckily 2003 5at does not have issues with cruise control with 3.5 and 3.7 gears. 3.7 highway cruising isn't bad, but the mpg difference shows: 3.3 gets 27-29, 3.5 gets 24-25, 3.7 gets 21-23. this is all freeway cruising at 75-80 mph.

turning tcs off will never allow slip to occur, which i had to do with the 3.7 gears. however, when slip activates, you cannot turn off tcs until the light goes off. i've done some rediculous testing and put my car in situations that the slip stayed on and wouldn't go off for more than 30 seconds. i did find a solution when this happens though: switch immediately to tiptronic mode and upshift so that the rpms jumps past 4500k. this will instantly kill the slip. strange...

sorry but i recently sold the 3.7 and shipped it up north already, i can however get more 3.7 for those interested.