Rear end noise after 3.73 installed in stock rear
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Rear end noise after 3.73 installed in stock rear
I just had the gears changed from the stock 3.23 to GM's 373 gear and had the bearings and seals replaced as well. It has been over 700 miles since and I spent the first 400+ miles being real easy on the gears and driving back roads to break them in.
Now, I am getting a noise from the rear when I am in reverse and turning and a slightly less audible noise when turning forward slowly. The noise is like a rubbing of metal, like the gears grinding.
Is this noise normal? Should I have changed the differential as well?
One more thing I noticed and it has happened only a few times is when I go WOT out of a turn I am getting wheel hop (which is probably due to the 25 mm rear sway and I need different schocks) but I also get a bad vibration.
More importantly, another thing that happened at a WOT in a straight line from a roll with no pedal it felt and sounded like the gear banged when I went WOT. That has me the most worried and wonder if it was a bad install or the differential from the stock 3.23.
Now, I am getting a noise from the rear when I am in reverse and turning and a slightly less audible noise when turning forward slowly. The noise is like a rubbing of metal, like the gears grinding.
Is this noise normal? Should I have changed the differential as well?
One more thing I noticed and it has happened only a few times is when I go WOT out of a turn I am getting wheel hop (which is probably due to the 25 mm rear sway and I need different schocks) but I also get a bad vibration.
More importantly, another thing that happened at a WOT in a straight line from a roll with no pedal it felt and sounded like the gear banged when I went WOT. That has me the most worried and wonder if it was a bad install or the differential from the stock 3.23.
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Originally Posted by Harley-Davidson88
It's hard to say, but it sounds like it might be your carrier.
The carrier seemed fine before. The only problem that I was told was a worn bearing. Also, isn't the stock WS6 3.23 a 3 series?
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3 series, CHK the pin ( the lock screw which holds the pin in place snaped off and allowed the pin to wallow around and elongat the hole in my carrier which allowed the spider gears to walk on each other
just my .02's Johnny
just my .02's Johnny
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Originally Posted by bolton98TA
make sure you have LSD additive in it, i made the mistake but forgetting about that once and i was haveing the same prob as you.
Funny you mention that. I just had the differential fluid changed with the 75w90 and was told the LSD is in it.
I do not hear the gears now but I have a creaking noise at the rear at WOT but suspect a suspension issue since the gears and sway bar change, but I am not sure.
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#8
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I'm not too sure but maybe it may be your stock diff. When I had my 373s dropped in, I bought a new diff too. I recently broke in my gears and dont hear any grinding or noises at either coasting or even WOT. Let us know what you find out.
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Originally Posted by 2001FireBird
I'm not too sure but maybe it may be your stock diff. When I had my 373s dropped in, I bought a new diff too. I recently broke in my gears and dont hear any grinding or noises at either coasting or even WOT. Let us know what you find out.
Thanks.
Did you go from a 3.23 to 3.73 or the 2.73 (not sure exact)?
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Originally Posted by ActionJack
Funny you mention that. I just had the differential fluid changed with the 75w90 and was told the LSD is in it.
Its cheap enough. Id say give it enough (an ounce or so) and go from there.
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Originally Posted by ActionJack
Thanks.
Did you go from a 3.23 to 3.73 or the 2.73 (not sure exact)?
Did you go from a 3.23 to 3.73 or the 2.73 (not sure exact)?
I went from upgraded 3.23s to 3.73s. To correct my last post, I DO have the same noise you get. Yeah I get it when I completely turn the wheel and just coast through, also when in reverse and place a gas I hear that funky noise.
I used Redline 75w/90 and was told that it did have LSD additive. I used about 1 and 3/4s of the stuff to fill my diff. I mean if adding more additive will solve the noise then sure I'll buy more.
Im not too sure what carrier I have, but Im guessing a 3 series? Dont really know, but if someone tells me how to know whats up, that'll help.
So yeah dude, this thing bothers me. I didnt notice this until AFTER i read this thread. I was like, aww man. Haha. So yeah, once either one of us find the solution, let the other one know. =)
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If the creaking is still there check the track bar behind your rear end. I had an annoying creaking and griding of metal sound too...turned out to be the track bar being loose after the install. now all I have is a vibration around 85 90. when i accelerate or decelerate within a few mile per hour its there but is more consistant if i cruise at around 90. Its not as intence when im at a constant speed but worsens with throttle change.
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I am still getting a noise from the rear when I am launching from a Dig at WOT.
I have tried to determine if the noise could be gears grinding or something else.
My thoughts right now are to get under the car tonight and see if the sway bar could be rubbing the G2 girdle or studs and look for marks. If no marks then I am back to square one but with one more thing checked off.
I will update later...
Since I changed the fluid and driven it some I have not noticed the noise any longer with turning or reverse. Hopefully, that took care of part of it.
I have tried to determine if the noise could be gears grinding or something else.
My thoughts right now are to get under the car tonight and see if the sway bar could be rubbing the G2 girdle or studs and look for marks. If no marks then I am back to square one but with one more thing checked off.
I will update later...
Originally Posted by 2001FireBird
I went from upgraded 3.23s to 3.73s. To correct my last post, I DO have the same noise you get. Yeah I get it when I completely turn the wheel and just coast through, also when in reverse and place a gas I hear that funky noise.
I used Redline 75w/90 and was told that it did have LSD additive. I used about 1 and 3/4s of the stuff to fill my diff. I mean if adding more additive will solve the noise then sure I'll buy more.
Im not too sure what carrier I have, but Im guessing a 3 series? Dont really know, but if someone tells me how to know whats up, that'll help.
So yeah dude, this thing bothers me. I didnt notice this until AFTER i read this thread. I was like, aww man. Haha. So yeah, once either one of us find the solution, let the other one know. =)
I used Redline 75w/90 and was told that it did have LSD additive. I used about 1 and 3/4s of the stuff to fill my diff. I mean if adding more additive will solve the noise then sure I'll buy more.
Im not too sure what carrier I have, but Im guessing a 3 series? Dont really know, but if someone tells me how to know whats up, that'll help.
So yeah dude, this thing bothers me. I didnt notice this until AFTER i read this thread. I was like, aww man. Haha. So yeah, once either one of us find the solution, let the other one know. =)
Since I changed the fluid and driven it some I have not noticed the noise any longer with turning or reverse. Hopefully, that took care of part of it.
Last edited by ActionJack; 08-22-2005 at 11:27 AM.