I have a TRE stage 3 tcase, an exedy stage 2 sprung clutch. Both have about 2000 to 3000 miles on them. Transmission has larger roll pins in the shift forks, and oem syncros in good shape. (also has about 2000 to 3000 miles on it.)

The whine appears under load, and when in neutral/clutch in from 60-65.

It appears under load from 71-73 mph.

I've done a lot of testing and I can say that

A.) The whine appears at both speeds regardless of gear
B.) If accelerating from 60 to 70+ there is no whine past 65mph.
C.) It is not like tcase death whine ( I had that, hence the TRE tcase...)


I am stummped and have no idea what this could be. It isn't very loud at all, but when I notice it I cannot ignore it. I changed by tcase fluid about 500 miles ago to redline shockproof heavy, but it did not help the whine, making me think it may not be tcase related. Any ideas? Transmission maybe?

Thanks guys!

 

I also changed brake pads thinking it could be some strange harmonic, and that didn't change anything.

 

I had the same thing in my IX. The car would resonate loudly at 75mph +/-2mph and it drove me nuts. Did a tire change as the old ones were worn and the sound vanished. Could be your tires.

 

+1 on the tires, an alignment/balancing could solve the problem

 

I hadn't thought about the tires as they are reasonably new...like 5 months, and not terribly worn. I will look into that, and def. get an alignment soon as I will be ordering some GTWorx springs in the near future.

 

Could also be your rear diff. When's the last time you've changed the rear diff fluid? Also, have you replaced any of the rear diff bushings or the mustache bar?

l8r)

 

Fluid needs to be changed, it was 25k to 30k since I changed it. Bushings and mustache bar are same ones that came on it new 50k ago. Why would these case a whine?

 

No, generally only aftermarket (polyurethane or solid mount) bushings cause some additional whine. I have the AMS mustache bar eliminator kit, which has solid aluminum bushings, and my rear diff will resonate (whine) between 55-60 mph and again around 75mph.

If it's been 25-30K miles since your last rear diff fluid change, you'll probably want to change it regardless, though.

l8r)