BrntWS6

iTrader: (7)

http://picosong.com/qrtc/


I recorded an MP3 of the sound my 9" is making. I've got about 40 miles on it since the install and did the recommended heat cycling of the gears. It does it all the time so I don't really think it's gear whine...I had that in my 10 bolt and it was a much higher pitch and only did it at certain mph.

You can really hear it kick in at the .25 sec mark. I've got my phone laying on the floor in the back seat so it's a bit louder than what I usually hear. I thought it may be TA noise so I put Butyl mat between the floorboard and trans crossmember but there was no change. Is this just normal driveline noise with a -1.5* pinion angle?

Long torque arm
Nodular Center section
S-Trac
3.90 Motive gear
35 spline axles

96lt4c4

iTrader: (5)

That's a noisy 9 inch. Doesn't sound right to me. Who set the gear up? Pictures of the pattern?

I have a Motive 3.90 in mine and it does not sound like that. I just get a slight whine at certain speeds. You have noise all the time...not good.

Has the noise been like this since the install? Or has it gotten worse?

guppymech

iTrader: (7)

+2 for what 96lt4c4 said. I wouldn't drive it any more till you check out that pattern and correct it. Maybe you'll be able to save the gears.

BrntWS6

iTrader: (7)

Its been like that since the install...very first drive. it has not gotten worse but I also have very few miles on it. Its a MWC rear.

I can get some pics of the pattern. I gotta pull the whole center section out for this?

guppymech

iTrader: (7)

Yep, to check the pattern the chunk has to come out. I just re-listened to your clip with headphones on, it's making more noise than I'd be happy with, although I have no experience with poly or rod ended suspension in these cars. Mine still has rubber bushings.

What does MWC say about it?

BrntWS6

iTrader: (7)

I sent Eric an e-mail as well. He can't tell me much yet so I have to get a pic of the gear pattern. I'm just not sure what to take apart to do that though.

I did a quick search and the pinion support has to be removed....so I guess the center section does not have to come all the way out. Are those the smaller bolts around and behind the pinion?

guppymech

iTrader: (7)

For now leave the pinion support alone. The axles have to come out, 4 bolts at each end of the axle tubes. Then remove the nuts that hold the center section into the rear end housing. Once you get the center section out then you'll be able to paint some ring gear teeth with marking compound and see the pattern. To change the pinion depth, that is when you remove the pinion support and change the thickness of the shim beneath it.
But that is getting the cart before the horse, get a look at the pattern and see what MWC says.

96lt4c4

iTrader: (5)

This is what my 3.90 pattern looked like.

BrntWS6

iTrader: (7)

Alright....in the E-mail from MWC he also said to just pull the pinion support and take a pic of the gears. I do know how to pull the center section since I assembled everything but really would rather not if I don't have to.

Anything I need to be aware of before I remove the pinion support?

96lt4c4

iTrader: (5)

You are just going to loose oil. Might drain it first if you have a drain plug, be careful not to bend the shims.

If you shine a light up inside the center section you should be able to see where the pinion is riding.

BrntWS6

iTrader: (7)

Thanks. Hopefully it just needs a shim or something simple.

wrd1972

iTrader: (12)

IMO, gets no better than that.

Guitar

iTrader: (9)

Yeah that's a lot. My Motive 3.90s whine some, but not that bad. Calms down towards 80 but can hear it below that sometimes pretty good.