Just Installed 3.90 Gears
02-28-2015, 03:53 PM
#22
I wanna say I had 4:10 yukons in my 95 m6 TA. They were fairly quiet. Next I had 4:10 Richmonds in my 96 M6 Z28 and they hummed like crazy. So annoying. Now I have motive 3:90s in my M6 00 SS. The motives are the best by far. I must say I enjoyed 4:10s over 3:90s. I feel like every gear pulled harder and 6th was even more useable.
03-01-2015, 03:51 PM
#23
These are the Italy made Motives? I'm trying to decide if I want to stopgap my 10-bolt with a rebuild kit and the 3.90s and buy a new rearend later this year. I need more gear in my combo, and I'm set on the 3.90s from Motive due to their quality vs the offshore crap.
03-02-2015, 04:38 PM
#24
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Well after confirming with a couple of mph apps. I'm at 2400-2450 rpms at 65 mph. Which is high, with 4.10's I was never that high. Has to be something up with this tranny then. If I factor in my 18/30/285 rear tires I think that's even bad I think the 18's should lower the rpms.
Last edited by karpetcm; 03-02-2015 at 05:12 PM.
03-02-2015, 05:15 PM
#25
I looked at some numbers, if you have a '93 T56 it has a .62 sixth gear, your tires have a diameter of 24.73 and 4.10 gears get you 65mph at 2250 rpms.
Count how many times your driveshaft goes around to spin the rear tires one revolution to see if you have 3.90s or not.
Count how many times your driveshaft goes around to spin the rear tires one revolution to see if you have 3.90s or not.
03-02-2015, 05:26 PM
#26
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I think I've figured it out. I have a M29 T56. Basically from what I gather if I put in 3.73 gears it acts as if I put in 4.10's. But it gets shorter in 6th, I think and acts as if I have 4.30 gears in 6th. Because it feels as if when I'm in 5th or 6th it just gets shorter in gearing. Not sure only explanation I can come up with.
I looked at some numbers, if you have a '93 T56 it has a .62 sixth gear, your tires have a diameter of 24.73 and 4.10 gears get you 65mph at 2250 rpms.
Count how many times your driveshaft goes around to spin the rear tires one revolution to see if you have 3.90s or not.
Count how many times your driveshaft goes around to spin the rear tires one revolution to see if you have 3.90s or not.
03-03-2015, 06:24 PM
#29
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I have 285/30/18 outback I wonder if I go to a 305/40/18 if that will get me from 105mph top of 4th to 110mph. Honestly even 110 is short. I think when I install my LT's I will get a tune have the limiter raised to 6200-6300 just to pick up more mph. I'll be installing 1.6RR as well with better springs. I do have to admit though M29 T56 with 3.90 gears and the car is completely different.
