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8.25 gear install gone bad..

B

bdavid

NAXJA Forum User
Location
USA
Well my uncle installed my gears and we have a big problem.......

WE installed a set of 4.56 gears in my 8.25 and when we took it for a ride it has a loud whine on acceleration and a grind when you are going about 15-0. We have taken this apart several times and have replaced the pinion bearings and races.

The gear pattern looks good and the pinion turned with 25 pounds of force.

I dont know what this could be it sounds like pinion bearing whine but they are new and i did it before we changed them.......

I think it is gear whine but from what?
 
I dont know if you mean 25 foot pounds,but it is supposed to be measured in inch pounds.

new bearings--15 to 35 inch pounds
original bearings 10 to 20 inch pounds

If its turning with 25 footpounds,that may be the problem.
 
Have you checked the axle bearings?

How do the carrier and pinions bearings look?

Did you put gear oil in it?

Any sort of locker, selectable, or limited slip?

25 inch lbs of torque to turn the pinion?

What are you using to determine its 25 inch lbs?
 
I did not set up the gears so i am not sure on the specs..

I thought he had said 25 pounds but it not sure.

It is full on fluid and it does not have any type of locker its open( open diff)

The only thing i can think is the pinion gear is to far back into the ring gear and when it is under a load it is whining. When the rear is coasting it lets the pinion go back to far into the ring gear

Does this make sense?? When the carrier is out how hard should it be to spin the yolk? How hard should it be to spin the yolk with the carrier in?????
 
Last edited:
grinding noise and a 25 ft-lb pre-load makes it seem as though he crushed the pinion bearings.

Ask him what did he get for the following:
-backlash:
-pinion pre-load:
-spanner nut torque:

did he get a good pattern?
did he re-use a crush sleeve?

Need more info first. The pinion should be relatively easy to spin with a finger of two (just the pinion no carrier or shafts), but it should not free spin when you let go.
 
its 10pm, do you know where your gear guy is?

URL%5D
 
So if i am understanding you, you have noise on decell? (when you let off of throttle) If this is so, it is likely that preload was not set properly on pinion bearings, or that the pinion races werent seated completely, causing the pinion to loosen upon driving the vehicle. There are multiple problems that it could be, but difficult to explain if you are not the one working on the vehicle
 
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