For those that did the swap to 4.56 gears, do you have any gear whine?

I just got my truck back with front and rear 4.56 with Detroit trutrack in the rear. I notice what I think to be gear whine, but only when the truck is doing between 55-60 mph. Other than that, I have no whine. Is this normal? Maybe break in period or the locker?

Gears are Genuine 4.56 if that matters?

Thanks for your input.
J.

 

The backlash may be set to tight!Or the oil may be to thin.Was the correct weight oil installed in the differentials?I have not had a gear swap yet,so I can't relate to the noise directly.

 

Take it back now!! It should make no noise if set up correctly. If you go too long, the noise will not go away without replacing the gears again.

 

Yep, take it back in. A whine in a certain rpm range is an indication the backlash is slightly off. Usually not catastrophic if it's minor and not constant, but it will wear a bad pattern in the gears and always whine if not set properly.

This is very common with a gear man who has done gears in Dana's but doesn't have a lot of experience with AAM differentials.

Properly set gears should not whine at all, anywhere in the RPM band and anybody who tells you it's normal or will go away is full of sh*t.

I've had Genuine 4.56s in my truck since '05 and they've NEVER had a hint of a whine...

 

Thanks for the input and help guys, will talk to them first thing tomorrow.
J.

 

Called them this morning and they came with a tow truck with no hassle. Great service.

 

Great, just dropped my truck off to have my Yukon 4.56's installed and now I'm worried. One of the guys there said that a little whine at certain speeds may be normal. I think he even said with it being due to aftermarket gears. I just hope I dont have any whine when I get it back so I dont have to take it back or have any issues. I am heading to Austin friday for the Heat Wave Custom Truck and Car Show, would hate to have an issue all the way there and all the way back.

 

No noise is normal. There is no reason for them to whine when properly installed.

 

I did Yukon 4.56, bought from Randy's Ring and Pinion with a master rebuild kit, installed by a good local trans and gear shop in an 06 FX4 and there is no whine at all with those gears for 3 years now.

 

Yeah, they covering their a$$ in case they don't get the backlash just right... No gears should whine at all if installed properly...