Hi guys ,


Weird problem happned to me , today I installed new rear Diff bushings the stock one was dead . So after when im done i drove the car so i found out the (thunk) sounds still there but not like before , then i speedup and start to hearing a whine from rear
The problem is the rear diff was fine non sound at all .

That do yoy guys think ?

 

The stock bushings hide a lot of the clunking noises the diff makes when turning, as well as the whining the make when they don't have a good wear pattern. Best course of action would be to get it rebuilt with a new ring and pinion and you'll be good to go.

 

Obviously, this isn't due to wear or you would have heard it before.

 

Simply not the case. Also, I didn't say it was fun to wear, I said "wear pattern", or contact pattern. The diffs aren't set up very well from the factory. The pattern is good most times. My rear diff was also quiet until I did poly bushing. New ring and pinion with proper setup, problem solved.

 

My Subie came from the maker with the rear diff set up wrong and it whines in the 55 to 65 mph range. Every car of this make and model for that year is the same. So, yeah, I know what you are talking about. If you want the noise gone spend the money and maybe fix it. But if you don't fix it, we are talking about a gear mesh problem that probably is not going to affect the life of the diff - only bother your ears.

 

Yea, and the whine is hellishly annoying, at least it was for me. Well worth the money to fix.

 

Actually not a weird problem at all.
You changed the stiffness of the bushings which changes the NVH transfer from the diff.
Now you can hear the whine which was there all along, its now being transferred through the body in such away which is making it more audible.

Now you understand the task the OEM has to do to hide NVH issues from the customer while still proving performance.

Completely normal.

 

Im about to remove the diff and open it lol .. Do u thibk if i order new OEM bushings will fix the problem ??? Or rebuilt it

 

Putting OEM bushings will make the noise go away in that you won't hear it because the bushings absorb it, the diff will be "making" noise. Rebuild it is the better option. You can get it done for around $1k.

 

What he said.

Rebuild is the best solution because it will reset the contact patch for the ring and pinion as well as set the lash. Usually it will be much better than factory specs.

 

The problem is there was no sound at all lol when i put the new setup of bushings the diff start to make the noise

 

How much if i get built one ?

 

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