I installed new Yukon 529 gears in my 4runner this weekend. I'm getting a low rpm rumble from the gears. Is this normal? I got my clearance set up at .008 backlash and the pattern looks Ok to close. The documentation calls for .006 to .010. It should work fine. Is this going to go away when the gears whare in? I'm not use to these lower gears. I did not change tires yet. The noise is coming from the gears. I put in Synergyn II oil in.

 

Noise should go away as the gears break in.

 

Cool, Do you know about how long it will take? I got 100 miles on them so far. I'm breaking them in just like Yukon sugests. 15miles, let cool down, another 15miles let cool down and so on. Now when I drive 30 miles the rear only gets up to 120 degrees F. It appears that the friction is reduceing and You could be right that the noise will eventualy go away. It seams like there is more rumble when decelerating that accelerating meaning that they could be whareing in.

 

Just talked to Randy's Ring and Pinion. They said the Pinion shaft is to close to the ring. I need to move it away about .005 of an inch then recheck the pattern. I'll try that.

 

I tore my rear appart and sent pictures to mikes ring and pinion. The said the pattern showed that the pinion is to close to the ring. Theys said I needed to shin the pinion .005 away from the ring. To make a long story short. That worked great. Now when I go down the road I no longer get any noise fron the rear. It was all in the set up.