| At about 200 miles after installation, I edged up to 65. Before that, there was no whine or gear noise at all. At 65, a slight whine was audible. I pushed up to 70 MPH and the whine disappeared. Played with it for a few minutes and discovered the whine is only between 65 and 68 MPH. After that, it's completely gone. Not objectionable at all as it is only just noticable and I don't spend much time at that range. I pulled over periodically to check the diff housing temp. When cruising at 55 MPH, the housing never got above 180 F (outside temp 70F). Later, I cruised at 65 for about 20 minutes. Checked the temp again and it was 230F at the hottest point. I'm going to guess the gears were at least 100F warmer. My guess is that this is far below any temperature at which the gears might go soft from improper break-in. If anyone want to know how I checked the temp, I used a Raytek ST-80 Pro IR gun set on max and scanned the housing. When I got near work, I checked 65 to 70 MPH range again and I'm almost certain that the whine was significantly less. I could barely hear it. It could be as the gear break in, it will disappear. At this point, even if it doesn't, it not objectionable. There is no gear whine at any other speed at all. Not even a little. So far I haven't gotten on it yet. In another 50 miles or so, I'll start driving more aggressively. It will probably not be until 500 miles that I turn the boost controller back on. Haven't really accelerated hard yet so there's nothing to report on SOTP impressions. The biggest change so far is low speed drivability is vastly improved. I have 18 wheels with 275 35 x 18 tires which made me a little too tall. Low speed drivability was never great especially off the line. That's all changed now and I'm about 6% shorter than I would be if I had stock gears and wheels.
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