3:73's are in, whine pretty bad! (Not Happy!)

**sworn** · 06-02-2011, 06:50 AM

So I just picked up my car yesterday after having a set of Motive 3:73's installed. I drove a few blocks home and thought I noticed some gear whine/howl.

So later in the evening, when I had more time, I took the car out again. There is definitely pronounced whine from the rear end which seems to occur when not under load IE not accelerating. Needless to say I'm pretty pi$$ed.

I'm taking it back to the shop where I had it done later today! I'm not a mechanic by any stretch, but I'm guessing the backlash isn't set correctly. I also know you can ruin the gears by driving them this way, I put a total of 20 miles on them......I should be OK, I hope!

**98maro** · 06-02-2011, 07:03 AM

Welcome to reality man.
My 3.73 are very loud and annoying
I changed the fluid 3 times also add additive and still there.
It starts around 35 mph. And stops at 80 mph

It an m6. My m6 had stock 3.42s no noise at all.

I wasn't happy with my either I'm still not happy but there's no way to fix that.
I had to get used to it

**Knight** · 06-02-2011, 07:17 AM

It's possible the backlash isn't set correctly. Motive gears are known to be a bit noisy though. My 4.11s in the 9 inch make a bit of noise, but not too excessive. I would have the backlash checked, but be prepared for some noise.

**GONZO SS** · 06-02-2011, 07:30 AM

Wow so if u pit gears on your going to get some noise no matter what. I was told that if u install them wrong u would get some whining ?

**sworn** · 06-02-2011, 07:32 AM

Welcome to reality man.
My 3.73 are very loud and annoying
I changed the fluid 3 times also add additive and still there.
It starts around 35 mph

Yeah, you can hear 'em even coasting at 20......

It's possible the backlash isn't set correctly. Motive gears are known to be a bit noisy though

I just dropped it off at the place where I had the gears done. They told me that they think the gear itself isn't "True." They are going to look into it and get back to me later this afternoon. I can understand some noise, but this is pretty damn annoying.

Does anyone know if Motive gears are known to be defective?

**Knight** · 06-02-2011, 07:36 AM

Originally Posted by GONZO SS

Wow so if u pit gears on your going to get some noise no matter what. I was told that if u install them wrong u would get some whining ?

You are right on both accounts. Improper setup will cause gear noise, along with wear. However, some brands are known to make noise even when setup properly. My 4.11s came with a note from the manufacturer, stating that they may make some noise. As I am looking for performance, I accept that. After confirming the gears are setup correctly, I do experience some noise. It is not too excessive though.

**Knight** · 06-02-2011, 07:39 AM

Originally Posted by sworn

Yeah, you can hear 'em even coasting at 20......

I just dropped it off at the place where I had the gears done. They told me that they think the gear itself isn't "True." They are going to look into it and get back to me later this afternoon. I can understand some noise, but this is pretty damn annoying.

Does anyone know if Motive gears are known to be defective?

If the manufacturer's casting/mold isn't true, it is possible. I haven't heard anything about Motive though. It's possible you may have just gotten a defective set, as will happen with any manufacturer occasionally.

**sworn** · 06-02-2011, 07:43 AM

As I mentioned, it only seems to whine while coasting not under acceleration. Is that indicative of improper backlash?

**35th-ANV-SS** · 06-02-2011, 07:48 AM

How loud is the noise exactly?

Do you feel it is excessive?

Loud noise is usually indicative of improper backlash, improper preload, or pinion depth is wrong.

**sworn** · 06-02-2011, 07:56 AM

How loud is the noise exactly?

Do you feel it is excessive?

Loud noise is usually indicative of improper backlash, improper preload, or pinion depth is wrong.

It's definitely noticeable, and yes it seems excessive.

Now that I've done some checking, it seems a lot of people report that Motive Gears are noisy. That, of course, doesn't make me happy!

I will post later in the day when the shop gets back to me. Stay tuned!

**tatertot91** · 06-02-2011, 09:08 AM

On my old z28 I had a set of used gm 3.73s installed and they were extremely quiet
Could always resort to that

**67CamaroRSSS** · 06-02-2011, 09:44 AM

The 2 sets of Motive 3.73's I had were whinier then a whore who didn't get paid...

The Richmond 3.73's were quieter but still made some noise.

The AAM (factory) 3.73's were the best but I welded the pinion bearing to the pinion after about 50 runs and some 2,000 miles. Damn sticky tires....

The above is why I now run a used set of 3.23's out of my buddies car. NO NOISE!!!!

**jrgswhitels1** · 06-02-2011, 10:42 AM

Sounds like you have to break-in your gears and all the new supporting parts first. All aftermarket gears will go through that whining stage. Once the bearings, lash and gears mesh altogether, it should quiet down considerably. Good shops will guarantee their work. Be sure to let them know what's going on, as to suggest perhaps a re-visit to your casing to check tolerances again to be safe.

**silverWS6** · 06-02-2011, 10:49 AM

My bet is that they weren't shimmed correctly, I had mine done and then took them back and after shimming a second time it was A LOT better

**Firebirdjones** · 06-02-2011, 12:49 PM

I've setup more rears than I can count. Generally speaking, once they whine, the wear pattern is established and it will never go away completely after that.
Only real way to fix it properly is to get another set of gears and start over.

99% of the time, rearends I've seen that had noise just weren't setup properly to begin with. To do one correctly takes time, patients, and correct tools. I've setup Motive, Richmond, and Yukon gears. All have been quiet for me if everything is spot on.
I prefer Richmond gears over any other, as they have backed their product and exchanged gears for me at no charge when I had a problem.

Hopefully your shop is a standup business and they'll make it right. If they tell you they'll reshim it, then be prepared for noise when it comes back, albiet maybe different intensity or different MPH occurance, but like I said, once you have it your stuck with it on that gear set. You'll have to start fresh to eliminate it completely.

The break in is everything from my experience. What I've always done, and is recommended by Richmond, is to run the car on the lift without a load on the gears. Run it forward for 20 minutes, then backwards for 20 minutes. Then let the rearend cool overnight completely. Then on the first road trip with a real load on the gears, take it easy for the first 40-50 miles with various loads, some coasting etc...Finding a nice long hill to climb and then come back down works good.
I then like to change the gear oil and recheck the backlash again. After that it should be good to hammer all you want.
Most shops don't take the time to do all this. They can't really, they have to get you in and out the door. Hope it works out for ya.

**sworn** · 06-02-2011, 01:22 PM

To all that posted thanks for the responses and insight. As of right now I don't think they're going to look at it until tomorrow. Apparently, it's not a priority which continues to elevate my pi$$ed of factor.

**02transamce** · 06-02-2011, 01:24 PM

I had Richmond 3:73 and Ford Motorsport 3:55 in my Mustangs,the Motorsport gears i paid a lot to get installed by a performance shop and the would whine slightly on decel,the Richmond gears i had done 'on the side' by a friend,whined like hell on acceleration,so i chalked it up to 'you get what you pay for' until i got the Moser 12 bolt which cost me 3 grand and it whines too.not sure which brand ring and piniom Moser uses but the ring gear looks good with no uneven wear after ten thousand miles.
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**TLS_Addict** · 06-02-2011, 07:59 PM

Sworn, that sucks man and I am sorry to hear that. I have the same gears as you and they make almost zero noise. pajeff02 was in my car and can confirm. They may be set up wrong. Now, once in a while I can get some noise in the rear but not from the rear, its the exhaust and I can hear the tone difference from the throttle I give it. They are known for being noisy but I am betting they are not set quite correctly. Hope they get it fixed quickly for you.

I drove mine pretty easy for about 500 miles. Hope to test them out this saturday at the track! lol

**98maro** · 06-02-2011, 08:19 PM

if they can get it fixed, i will take mine to the shop, mine is getting louder everytime. now i cant even have a conversation while im drivingo on the highway.. is almost as loud as my exhaust...

is very annoying