set backlash to 5 book said between 3 and 10 i have a humming noise on deceleration what are your guys thoughts car is a 66 ss impala 12 bolt put in a 373 thanks

 

Pinion gear depth is also as important. I presume you were following directions for the whole procedure? Also make sure your oil level is full.
What brand of gears? Some make noise by nature.

 

Are they new or used gears? What brand of gear? Highway or drag R&P set? Did you do a paint and pattern? ed

 

they are slightly used a friend had them in his car he wanted a road gear we did a paint pattern, i think we are going to set at 8 instead of 5 backlash i have to ask him when i go back to work for the brand i took it apart today first time doing this can you tell lol

 

yep but its our first time doing this

 

Sometimes a used set of gears , especially if they were
set up improperly the first time, will make noise no matter how they are set up now. An old mechanic told me this years ago, not sure if old wives tale or not, but he said once a gear gets warn in improperly you can never
straighten out the origional error. No way of telling if that is the problem.
I would,as mentioned previously, make sure the pinion depth is set
corrrectly and at the proper preload then set your backlash. Keep us
appraised of your progress. ed

 

well it is a richmond gear we took the pinion out and the crush sleeve didnt get crushed 120 psi air gun couldnt do it ?????????

 

Sometimes those crush sleeves are really tough. I have used up to a 3ft.
extension to crush a new sleeve,so put away the air gun and hunt down a big *** pipe. Make sure to crush the sleeve and check the drag on the pinion with an inch lb. torque wrench and then check the pinion depth. ed

 

thanks thats the plan for wenesday night we going to jack the car up more for elbow room get 1/2 or 3/4 ratchet with a 3 foot handle from a friends shop and his inch lb tor snap on wrench keep your fingers crossed

 

Good luck, Alot of people go blindly into changing a ring and pinion,I
believe its one of the more difficult operations to carry out ,that
is if you do it correctly, if you dont do it correctly the differential
will definately make you aware ! Take your time and bring alot
of patience with you. ed