Noisey Gears???

[rdmorrow]

I am a new member to Stangnet. This is a great site.:SNSign: I have a 2006 GT(automatic trans). I want to keep it naturally-aspired. However, I do have a C&L CAI, UD pulleys, Corsa Axle-Back, dyno tune, etc. After researching all of the discussions regarding gears, I decided to swap my 355's for 410's. I had Eibach pro-kit springs, 410's, and Steeda billet LCA's installed yesterday. Immediately after leaving the shop, my reaction was WOW. This reaction changed very quickly to WHAT THE HECK! I heard what I thought was my 20 inchers rubbing. Closer listening seems to be a whining sound from the rear end. This sound starts after I hit about 50mph. It stops after I accelerate to about 70-75. However, when I deaccelerate and actually take my foot off the accelerator, the whining continues until I come to a stop.The tech said that it was likely the gears, and that it would probably go away.The sound is obnoxious. Any suggestions on what this could be? A set of bad gears? Improper installation? Gear friction reducer fluid needed? The gears are Ford Racing. The shop is a reputable mustang performance shop.

 

[JTGrant]

with install of the lCAs, if the gears aren't perfectly installed then you are going to have more noticeable noise from the gears. Reason being that the LCAs use polyurethene bushings and they transfer more noise and vibration. I have this same issue on my car after installing the lcas. I just setup my rearend again this weekend. I cleaned up the drive pattern pretty good, the coast side is okay. I haven't installed the arms again but I plan on it soon. I noticed this after install the control arms and then I put the stockers back on. I did post a thread on this in this forum. I wish I had taken more time and care the first time I set this gears up, because now this is already a pattern worn into them.

 

[Mossberg]

I vote for improper installation. Have the installer check the backlash.

 

[JTGrant]

and the pattern

 

[anthony05gt]

That's correct. The backlash and gear mesh pattern must be set correctly or you'll have problems. The backlash could be on, but if the gear teeth do not mesh in the right area of the teeth it's trouble. It is true about the poly bushings in the LCA's causing more noise transfer.

 

[rdmorrow]

Noisy Gears

Thanks JT, Anthony, and Mossberg.
I will take it back to the installer armed with some new information.
The performance is amazing with the 410s, but the whine takes some of the fun out of it.
I did not realize that the billet LCAs would transfer the noise so much.
I believe that it is probably the backlash and gear mesh pattern.
Now I won't sound like a naive dumbutt!
I will eventually post pix. 2006 Mustang GT Performance White with Painted Red Shelby stripes, Roush louvers, CDC chin spoiler, honeycomb rear panel, and midwest mirror covers. 20 in voodoo wheels. Not bad for a 46 year old going on 18! Thanks again!

 

[Kiernan]

I was under the impression that autos all came with 3.31's and manuals got the 3.55's.

I also had the same issue as you when I went to 3.73's. I put in Motive gears, then paid a fortune to have them replaced with FRPP gears only to have the exact same issue. Finally, I had the shims replaced and instantly, no more noisy gears.

I'd highly recommend that anyone installing gears on an 05+ get some replacement shims along with the install. The OEM shims don't play well with replacement gears.

 

[JTGrant]

the shims are the problem, it is the person who sets them up. With gears that are larger in numerical number the harder it is to have a silent setup. You have you get the proper pinion shim (Pinion depth), backlash (carrier shims) and pattern. I have a perfect drive side but the coast is okay. Still a bit noisey from 75-80.

 

[rdmorrow]

Noisy Gears

Once again...thanks JT and Kiernan for the feedback. Coast side/drive side/shims/pattern...I think that I have it now. I thought my Stang had 355's. I could very well have been mistaken. If they were 323's, perhaps I should have went with 373's?
Anyway, I have another problem to add to my list. The same shop installed my Eibach ProKit springs. The front wheels are about 1/2 in. further in at the top of the tire than at the bottom. Not being an automotive expert, I do not know if this is what is referred to as a "camber" problem...I also do not know how such an issue is fixed.
Im learning...then perhaps I can contribute more.

 

[Black2006GT]

there is a camber bolt kit available. I dont know the part #, but I bet any Mustang shop like Steeda has them

 

[JTGrant]

brothers performance sales a camber kit for 120.00 I think.

 

[rdmorrow]

Noisey Gears

I found the part...Eibach Alignment Kit part #5.81260K. Thanks!
RD