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Gear whine ... or not? ATTN: Guys who know race rear ends

  • Thread starter Thread starter 89MustangGX
  • Start date Start date Apr 30, 2004

89MustangGX

I have nothing productive to add!
Jul 3, 2001
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Mill Creek, WA
stangnet.cardomain.com
Apr 30, 2004
#1
  • Apr 30, 2004
  • #1
Hello,
I somewhat recently put the back half of my car back together -- and now that I've had a chance to drive it I'm wondering if something might be wrong.

I have UPR upper and lower control arms, the uppers are solid mounts, the lowers have one solid one poly mount. I have all the seams and torque boxes welded up, along with torque box reinforcements upper and lower bolted and welded in. The rear end is a Strange Pro Race Spool, Pro Race 33 spline axles, with the ends milled, 4.30 FMS gears, and a stud girdle -- Mobil-1 gear oil. I have an FMS Aluminum driveshaft. It's supposed to be set up with the tolerances loose...better for racing. Alos note I have no insulation or sound deadening in the car.

Anyway, I initially drove it, about 10-15 miles and it was really loud the whole time. I brought it to the person who put it together, we took off the driveshaft and he felt the preload -- said there was none. Said something must have slipped. So he put some more preload on it -- tightened the pinion nut, I guess that's what it does.

Now driving it around, I put some more miles on it and here is how it acts now: It whines -- when just cruising around it's very loud -- hard to have a conversation in the car with the windows up. When accellerating it get's a higher pitch whine, but much, much quieter. When I take my foot off the gas, it's almost silent.

What does this sound like? Normal -- just getting nosie from the big gears and everything being solid? Needs more preload? Something else wrong?

Any input is greatly appreciated -- I'm wanting to make sure it's right...I have alot of money invested in this and don't want to ruin it (if it isn't already!). I am across the country from the guy who did the rear for me, so if it needs attention I will have to do it myself or have someone do it -- so anything that can help me would be a HUGE help.

Thanks!
 
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