View Full Version : Is buying a aftermarket rear end.....

06-14-2006, 01:50 PM
.... like throwing the dice when it comes to getting a loud (whining) rear end?

It seems to me that when it comes to ALL of the types... 12bolt, 9", or S60 that its pretty much a luck of the draw to get a quiet rear end. Am I right on this? Reminds me about how some people get a quiet Procharger and some get a loud one, luck of the draw.

When you get a loud/noisy rear end is it safe to say that it wasnt been put together correctly? Or is it just that the noisy rear ends have gears that may have been cut a tad differently, maybe dull tooling when they were cut?

Im about to order a rear end.. Im not buying anything I have to assemble.. ordering something that is direct bolt in. Probably a S60. Im wondering what I should expect.. or what I should do if I get a really loud one.

So whats the deal between loud and quiet rear ends?

06-14-2006, 02:28 PM
It is just the nature of the beast, really. All aftermarket rearends. Mine was quiet at first but as soon as I started racing it, it only got noisier. It was not set up incorrectly and there was nothing technically wrong with it, it was just noisy. Having an aftermarket torque arm only made it worse.

It's really something you need to think about - if you are willing to sacrifice quiet for strength. To me it was a no-brainer but I know not everyone wants to put up with the noise.

06-14-2006, 03:01 PM
Yes, it's somewhat up to chance--even when it's assembled correctly. It depends on what you call loud too. The rear end shouldn't howl so loud that it drowns out your stereo. Also, performance cut gears will have some whine to them--the stereo drowns that out.

I bought a Ford 9 inch just for that reason. My first set-up was too loud for my liking. I pulled the center section and had the gears re-set. Much improved and I'm happy. Yes, it cost me $125 and the time to pull and replace the center section. But I don't have to hear a howling noise that drowns out everything else and makes it hell to drive your car.

06-14-2006, 03:03 PM
Thanks.. thats kinda what Im gathering. The funny thing is my stocker doesnt whine at all, maybe a small hum at 70mph.. Ive beat the living hell out of my 10bolt at the track, I mean some really nasty clutch dumps (3500+rpm) and out of all the hard launches Ive only spun a couple times... meaning the rear end was taking all the abuse.

I hear ya though... I guess I could try diff fluid additives if I get a loud one, I heard sometimes that helps. I rather have a bullet proof rear end and be able to lift the tires rather then clinch my teeth each time I launch with the stocker or a 12bolt.

Its just odd how some people get a real quiet one... and some get rear ends that are unbearably loud. I do take my daughter with me and my wife on trips once in a while and Id rather that she didnt have to wear ear plugs. lol

06-14-2006, 08:08 PM
When I put in my strange 12-bolt with 4.10s, it was dead quiet. Then I went to the track, launching at 5,500 on sticky tires, it whined after that.

Then I put in 4.56 gears, did the install myself, made sure the pattern was good. They were dead quiet until I went to the track. On the freeway driving home I noticed a lot of coast whine.

Needless to say, I'm begining to see a pattern. :devil:

06-16-2006, 01:06 PM
i wonder why stock 10bolts dont make noise after being beat. i would say they are made better but that would be retarded sense they break so much. so anyone know what causes the noise

06-16-2006, 01:49 PM
i wonder why stock 10bolts dont make noise after being beat. i would say they are made better but that would be retarded sense they break so much. so anyone know what causes the noise

Its not the rear end tat are 8breaking in 10 bolts......its the gears...

06-18-2006, 11:07 PM
I would have to say it's a combination of set up and materials.

Matrials) I have found that the new S60 and 12 bolt castings are soft and that is why most rears start out quiet and then after some track time they distort and the centerlines are not true anymore. I do not have a Rockwell Hardness tester to verify this but when I build a 12 bolt and have to pry the case out a few times during set up on the case where I pry from gets gulled up easily. I do not see this on any other OEM case I build! IMO the only way to go is a Ford 9 inch in a nodular Strange casting with Motive perfromance or Strange gears.

Set up) I have built many assemblies and I have a very low return rate. I have built many replacements for customers that have had issues with their Moser assemblies and a few others out there. I have had my share of bad gear sets with one being an oversized pinion bearing pilot on a Strange 9 inch gear set and I warrantied with no questions asked. I'm still waiting for an answer from Strange on that gear set.
The aftermarket is no better than the OEM's when it somes to quality but keep in mind that the aftermarket is not investing R & D time and money into producing quiet gears, they just want them to hold up to the power you guys are putting through their components.

06-19-2006, 03:04 AM
Thanks Scott!

06-19-2006, 02:02 PM
LOL, nice sig! :drive: