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Discussion Starter · #1 ·
Hey everyone... i have a question... I installed gears a few days ago, well not personall me... but a guy did... anyways, they make noise as im sure some of you know by now... when locked in the gears make noise on deceleration but when accelerating they are quiet... they only make noise in 4high, because 4low is too slow. This is my problem though, I think that I can still "feel" them turning when I am in 2wd, it is kinda of a whirling/humming/deep vibration... But, it goes away at faster speeds... :think: It doesnt do it slow (about 15-35mph) it does it in the middle (about 40-60mph) but then once you get movin good up around 70 or 80 mph, it seems to "dissengage" and they are quieter... isnt that weird? Is that the speed that they stop turning or when you cant engage 4high anymore or something... and thats why they get quiet again? So for the real question... am i making this up or do my front gears turn while im in 2wd? My truck is a 2003 with the newer transfercase so it doesnt turn in 2wd... so I know power isnot going up there.... but maybe the cv's are still spinning them and they are being noisy? I dont want to hurt these things! But im back up in gainesville, and in a week and a half the guy is gonna recheck them for me.
 

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What size gears?
 

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Discussion Starter · #4 ·

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Bayou Surface Drive, LLC
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Your gears do not spin in 2wd. They have an actuator that locks in the 2 peice passenger side axle shaft in 4wd. The cvs do spin all the time.
as for decellerationg noise, i read on randys ring an pinions site that loose pinion bearings will make noise upon deceleration ans will any worn bearing. My guess is the PBPL(pinion bearing pre load) is too loose or CBPL (carrier bearing Pre load) is too loose. Keep us posted.
 

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Discussion Starter · #6 ·
Your gears do not spin in 2wd. They have an actuator that locks in the 2 peice passenger side axle shaft in 4wd. The cvs do spin all the time.
as for decellerationg noise, i read on randys ring an pinions site that loose pinion bearings will make noise upon deceleration ans will any worn bearing. My guess is the PBPL(pinion bearing pre load) is too loose or CBPL (carrier bearing Pre load) is too loose. Keep us posted.
hey maxxis, if that was the problem... would that make the diff make that whirling I am descrribing while in 2wd also? or only 4x4? thanks!
 

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Bayou Surface Drive, LLC
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in 4x4 obviously. If its pinion or carrier bearings.
Now it could be the halfshaft support bearings int the differential, but all that is usually changed out when regearing
 

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Discussion Starter · #8 ·
well, yeah I did get a complete master install kit to go with the install, so all that should have been replaced right? ... its just weird... even in 2wd like I said earlier... the truck is just "louder" down in that area... I mean, I can feel it in the pedal of my truck even... Maybe im just really anal, cause I really get to know my personal vehicles.. so maybe its just the nature of the new gears or setup or something.... or maybe im feeling it from the rear end... i dunno... its just confusing because i know there is a problem in the front... so in theory I shouldnt notice it unless I was in 4x4... but i know it feels way different than it used to... I dunno...
 

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Discussion Starter · #9 ·
hey, so the cv's always spin so the outer axle shafts spin too... but not the ring and pinion... could maybe when the bearings got replaced now the outer axle shafts are put in a little different or just feel different with it being apart and then put back together??? Im just trying to find anything i can think of as why it would feel different in 2wd... im not making this up... it does make a pretty decent whirling noise that it didnt used to and im not used to... does anything in the driveline spin at a different speed now that I have different gears?? I dont know what im looking for here!?
 

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Discussion Starter · #11 ·
hey could maybe the actuator not be fully disengaging the axle sleeve thingy so its still spinning the gears or something?? and the transfer case is unlocked?? so no power but it still makes a noise?
 

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Pat McCrotch
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I honesty dont think any of the above mentioned things are your problem. You made a huge gear ratio change. Its a high (numerical) gear ratio. Its going to whine some and I bet the added rpm of your driveshaft is what you are feeling. You driveshaft is spinning much faster now than before. Combine that with your most likely already not perfect pinion angle and you have a vibration. Your whining sound is probley the rear gears. But...

If you want to make sure the actuator is not partially engaged just pull it out of the front diff and look at it. Hell even plug the hole, unplug the actuator ( so it doesnt get fucked up) and take it for a drive. This is just for your piece of mind but I bet you are just the kind of guy that totally anal and is noticing everything. Not a bad trait to have but sometimes will cause you to loose hair when not needed..............Goodluck
 

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Bayou Surface Drive, LLC
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To answer your question, your drive line is spinning much faster now. So say if you had no vibs before, now you could due to increased driveline speed that was never felt unless you say go 100 MPH. Just an example
 

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Discussion Starter · #14 ·
ohhhh... i see... but howcome it seems like i can feel it up front in 2wd?? Do you think maybe Im feeling vibration from the rear up front? maybe i might need to get my shaft rebalanced or something? Also, doesnt it seem like it would get worse with speed? because it seems like it goes away when i go fast...
 

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Bayou Surface Drive, LLC
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Your d shaft spins all the time IIRC. It wasnt until 06 when they dont spin in 2wd
 

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Discussion Starter · #16 ·
wait.. what? it does? i thought that since 4wd is not engaged it didnt spin, cause i can go out and grab it right now and it will spin freely... thats what ive always heard.. and the same reason cognito said i didnt need a new front cv dshaft...
 

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Bayou Surface Drive, LLC
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Shit most auto trac t cases spin in 2wd. But i dont own a truck with auto trac until this after noon :D Maybe someone else will chime in, I dont want to give you false info
 

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Discussion Starter · #18 ·
ok, im pretty positive i know what the problem is... I talked to Stephen (dark eternal) and we talked about the actuator... basically the truck makes the sound in 2wd and then when you hit the 4high button it gets louder! and then it all of a sudden goes away and is perfectly quiet! So I think when its in 2wd its not fully dissengaged so the collar inside there is rubbing, and then it engages fully in 4x4 and is quiet. So what im gonna do is go get some 80/90 gear lube and pull the outter tube and look at the sumbitch! Any advice? Oh and thanks for the help!
 

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Bayou Surface Drive, LLC
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HAVE THE GUY WHO DID THE GEARS DO IT. He disassembled the diff do make him do it.
 

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Discussion Starter · #20 ·
well, the thing is... im up here in gainesville now, and the noise is pissing me off... i dont think it will be that hard cause all i gotta do is disconnect the cv and the outer axle tube... im 2 hours away from home now... so... i dont really wanna drive it for two weeks how it is... he is already gonna have to fix the pinion depth because the gears make a different noise in 4x4... on the decelerating side... he already said he would do that.
 
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