Anyone with 3.90s or 4.10s have a slight increase in gear whine?

[Cobra4B]

Drove the car around more tonight (top up this time with storage covers off and left in the garage) and there's a definite increase in gear whine... it's not major and if you weren't anal like me or looking for it you probably wouldn't notice it. I had the rear go bad in my Z06 years back and it started to howl... this is nothing like that. However, it is more than stock and more than my Z06 in it's present state.

It's most noticable at decel from 60ish and slow accel to and past highway speeds.

My question is if this is inherent to the lower gear sets like the 3.90s and 4.10s? I've seen posts that swear more gear noise is the nature of the beast with anything over 3.73s and that in F-bodys Richmond gears even publishes this info for certain ratios.

Other posts have been adamant that a rear end can be made dead silent no matter what the gear ratio... Phil @ DTE has some very lengthy posts on this. I'm curious if others that have gears also have loud exhausts so they "think" the car is dead silent. My Corsa Extremes a literally silent arund 1400-1600 rpms... I'd wager they're even quiter than stock.... so anyone w/ aftermarket 3.90s/4.10s have any input?

I'm going to try to meet up w/ Racin' Jason to compare to his FRC w/ 4.10s.

G'night.

B

PS - Kevin.... not complaining at all or implying that you sold me anything defective. I know they served you just fine for 20k miles and a faulty rear setup will show it's face instantly or it'll get bad in a hurry. I expected some of this and the performance gain is well worth a little gear noise over stock :yesnod:

[WKMCD]

The only time I noticed any increased noise or vibration was the 15 minutes I had the PFADT tranny mount/brace in there but that is pretty much a solid mount and transmitted everything. I also have sound deadening and a 800w sub in back. FWIW: I never once worried about the rear leaving me stranded with 520/480.

You worry too much. :willy:

[Sneaks]

I don't remember hearing any gear whine when they were in Kevins car.

[allthrottleandsomebottle]

My rebuilt ZIP 3.90's in the 97' whine on decel..........but...........thats.....cause.........my........thrifty............ass............reused the original gear set with 13K hard miles. Its all good though cause the reuse/reshim/new bearings is 50/50 on no whine. Its very slight and ok with my exhaust any way. Brian, turn up the tunes or get LTs......:D

[Cobra4B]

You worry too much. :willy:
I know.... I just like answers/figuring things out... again... this isn't a howl and you wouldn't notice it if I didn't point it out. Plus I'm sure my car is a good bit quieter than yours (exhaust wise) and I don't have a trunk full of sound deadening and subs.

The noise isn't indicative of a problem and it's probably been like this from day 1. I'm of the opinion of drive it until something changes/gets worse then you know you have a problem and can pin point it. My gut feeling is that the Motive higher ratio gear sets produce slightly more gear noise than the OEM getrag 3.42. However, most people who get gears also have a noisey exhaust or engine work or both. I just wonder how many people who claim their diffs are 100% OEM quiet really are. Just trying to compare.

I don't remember hearing any gear whine when they were in Kevins car.
You old guys just don't hear the higher frequencies ;) It's not really a gear whine in the classic sense where they're singing loud and clear.... it's very mild, but it's there and more than w/ the 3.42 diff in the car.

My rebuilt ZIP 3.90's in the 97' whine on decel..........but...........thats.....cause.........my........thrifty............ass............reused the original gear set with 13K hard miles. Its all good though cause the reuse/reshim/new bearings is 50/50 on no whine. Its very slight and ok with my exhaust any way. Brian, turn up the tunes or get LTs......:D
Haha.... yeah top down and radio on it's fine.

[Cobra4B]

Took her out for lunch.... top down windows down stereo on there's nothing to hear so nothing to worry about ;) I can hear a faint gear noise over 60, but it's easily ignored w/ wind noise and/or the radio.... guess it's just my nature though.