Awd Gearing

[jaxxon]

Hey all,

 

Has anyone swapped front and rear gears lower than 4:10's? I'm going to be dropping in a SMC performance built (converted) GM crate LS3 (500HP/480Torque) and really should replace the stock gears w 150K on them right?

 

As far as the transfer case, I have a rebuilt NV-149 has 20K on it and will implode I'm sure but have a 100k warranty on it. Any tips with that? Beef it up?

 

So.... Trans is coming from RPM: it's a 4L60/65E level 6 w/3000 stall---- My question is should I stay with stock diff gears or go lower? I do use truck to pull my roadracing bike rig (20ft trailer)

 

These projects are NEVER done, it's all coming back to me after not building a muscle car/truck for 10 years :blahblah:

Edited March 16, 2011 by jaxxon (see edit history)

[silverado777]

What size gears are you looking at going with?

[04CHASE]

i just went to 3.73's in mine . havent got to drive it much but it should be stronger since the pinion has less larger teeth.

 

for your setup the 4.10's should be fine . i wouldnt touch them . towing you will gain mpg as well as highway mpg keeping the od in a lower rpm.

 

off the line youll be a bit slower though, again this is where i needed the 3.73 since traction was absent for me.

 

4.10's will dp best performance wise in 99% of the trucks on here. some have even gone to a 4.56 for even more out of the hole .

[silverado777]

I would say stick with the 4.10's and swap to a 4l80e tranny which has a higher 1st gear ratio to help get some traction.

[jaxxon]

i just went to 3.73's in mine . havent got to drive it much but it should be stronger since the pinion has less larger teeth.

 

for your setup the 4.10's should be fine . i wouldnt touch them . towing you will gain mpg as well as highway mpg keeping the od in a lower rpm.

 

off the line youll be a bit slower though, again this is where i needed the 3.73 since traction was absent for me.

 

4.10's will dp best performance wise in 99% of the trucks on here. some have even gone to a 4.56 for even more out of the hole .

 

Yes! I've seen your truck on YouTube video's and read an article somewhere about the build. That truck is the king of SSS's fo sho... What a bitch it was to covert a 2008 era GM crate LS-3 to work in a 2004 SS!

 

Do you think the rear/front end gears (w 150K on them) will hold up with the new HP/Torque?

 

Lastly, so why an 4L80 over a 60/65? JJ

Edited March 16, 2011 by jaxxon (see edit history)

[jaxxon]

I would say stick with the 4.10's and swap to a 4l80e tranny which has a higher 1st gear ratio to help get some traction.

 

keeping AWD...

[04CHASE]

the ls3 uses a different reluctor so i imagine you had some fun , rebalancing bottom end and all.

 

@ 150k , on the diffs, you would want to rebuild them complete if your going into them . until then i would run them as is.

 

depending on your goal of hp , a built 4l65e may be fine . the 4l80e is great , reliable and somewhat easy swap (new driveshafts/custom x member/little wiring/tune/and the t -case input gear swap) . if you plan on keeping it shy of 600 awhp id probably do the built 65e.

 

the trans is your weak point this far. everything else on the drivetrain is somewhat stout for being stock.