nwilson44

Well guys I am of the opinion that as soon as I have the money, this 10-bolt is going in the trash. The only thing stopping me is that I have yet to find a watts link that works with the 9" I want. Anyways I won't have the funds to do that until this summer anyways. I am throwing a new front end on the car.

The issue I am having is that my pinion bearing took a dump last spring. So I found a bolt in replacement but it was a 4-channel (mine is a 3). So I bought a motive 3.90 gear set, rebuild kit, and inner bearings. I had it installed. The rear end is unbelievably loud. I have Longtubes, ORY, and SLP Loudmouth II.... I can easily hear it over the car...

My mechanic does many things well but I don't think this is his forte. I drove it for 2 months just howling away. He finally got the car back and he told me that the "gear pattern, looks almost perfect". He believes the noise is coming from axle bearings and bad axles, and the possibility of a bad torsen.

Does this sound right? I just need something quiet that will hold up for 6-8 months till I can save up some more cash (just bought full UMI front suspension with Koni's). Any Ideas?

01ssreda4

iTrader: (96)

The 3.90 gear is an orange box gear correct? Part number g875390? They're noisy from my experience.

nwilson44

Yes they are orange gears. I was told they'd be a little bit louder. They are excessively loud. Not sure what gives.

01ssreda4

iTrader: (96)

Does the noise go and come with speed, like in a certain speed range?

nwilson44

It's always making the noise but it gets louder with speed.

01ssreda4

iTrader: (96)

Hmmm, sounds more like a bearing or other internal issue to me then. If the gears were off a little they would whine or howl at certain speeds like for instance 40-60mph is common.

flintwrench69

iTrader: (11)

When I had a 10 bolt it had 3.73s. I put new bearings in it 1st year as the posi unit lost a clip & hogged the posi unit. So new used lt1 posi & all new bearings. Fairly quiet, still slight gear whine. After a few track days, noisy. Got much louder as the summer temps rose. At 90-100 degrees out it was brutal! When it cooled off it got quieter. I've checked the backlash on it, wasnt excessive. I think it was gear whine. It never let go but I bought a 9 inch before it did & got $$ out of it!

nwilson44

nwilson44

How's it look?

stevenc1703

What is your pinion preload set at? I was having noise issues too and rebuilt the rear, the pinion was about 1 in lbs now its at 7in lbs which is proper for reusing the original bearings, 15in lbs if your using new ones. what is your carrier preload? Should be around 20in lbs. What is your backlash set at? It should be between .006 and .010. You could try some torco oil too, should run quieter than other oils. I'm not an expert so I might be off on some of this but I was having issues myself and these things fixed my issues.

N20zuki

Used bearings is 10-15 and new is 20-25in/lb.... Backlash should be etched into the ring and pinion...

OP the coast and drive contact looks good

stevenc1703

Is the with the carrier or just pinion?

01ssreda4

iTrader: (96)

Those are just pinion figures.

stevenc1703

Oh well, I'm not changing it now lol.