a_reyes1014

iTrader: (1)

Hopefully someone can help out on this one but i was having problems setting pinion angle for awhile and finally got it to where it doesn't vibrate anymore. Now i hear a sort of whining noise out back only in fourth and fifth and only when i'm on the pedal. When i let off the pedal and let it cruise while in gear or neutral it stops. The setup for the rear is a ford 9" with the stock bracket locations. If anyone has an idea what to look for i would appreciate the help. Thanks.

ultimatejay

iTrader: (1)

Sounds like you may have a ring and pinion not properly adjusted/installed. The only thing that is throwing me off is that it only happens in 4th and 5th.- But that could just be speed related.
Is your driveshaft balanced?

a_reyes1014

iTrader: (1)

yea had it rebalanced last week. about how much backlash do should you have for the 9"?

a_reyes1014

iTrader: (1)

before i put it in i had .0010" backlash

a_reyes1014

iTrader: (1)

ok i rechecked my tooth pattern and everything checks out. could it be possible that while im putting a load in those two gears that the driveshaft is going positive.

13B-RX3

iTrader: (2)

Did you check your gear pattern on the decel side? It sounds like that may be where your problem lies.

a_reyes1014

iTrader: (1)

now is that coast side or drive side
of the ring?

13B-RX3

iTrader: (2)

Coast side. If thats where the noise is present thats where the problem is going to be.

a_reyes1014

iTrader: (1)

the pattern is right in middle. its actually when im on the gas i start to hear it. i can only hear it in 4th and 5th gear. 5th gear is actually worse.

13B-RX3

iTrader: (2)

How much preload do you have on the bearings that hold the carrier? If it's too little the carrier could be moving around under load. Were all the bearings replaced?

a_reyes1014

iTrader: (1)

i have preload set to about .0012"

13B-RX3

iTrader: (2)

Explain to me how you loaded the bearings (backlash).

a_reyes1014

iTrader: (1)

if i want to reset backlash and preload before i put it in the car, do i have to reset pinion depth?

a_reyes1014

iTrader: (1)

first i set preload with no backlash then i set backlash to about .0009"-.0010"

13B-RX3

iTrader: (2)

How did you set the backlash? That could be the problem. It's hard to explain but i always leave the bearing that is farthest away from the pinion alone and set the lash by cranking the other adjuster in essentially spreading the case and loading the bearings. If you don't have enough pressure on the bearings they will let the carrier move.

a_reyes1014

iTrader: (1)

that does make sense. by leaving the furthest one alone do you mean with no backlash first then adjust with other?

13B-RX3

iTrader: (2)

Instead of loosening the adjuster on the opposite of the pinion to get your backlash, you force the ring gear away from the pinion with the opposite adjuster.

a_reyes1014

iTrader: (1)

so you are setting backlash and preload at the same time? does the pinion depth have to be reset?

13B-RX3

iTrader: (2)

It shouldn't. That would be the last step.

a_reyes1014

iTrader: (1)

im sorry for all the questions allen but could you explain exactly how you do it? im still fresh to suspension and drivetrain.

13B-RX3

iTrader: (2)

No problem. It's one of those hard to explain things and i would really have to show you. How did you set your bearing preload on the carrier? It sounds like you just don't have enough preload.

a_reyes1014

iTrader: (1)

well i set it with no backlash in it to .0012" then turned to adjusters toward where the backlash needed to be set if that makes sense

13B-RX3

iTrader: (2)

How much pressure do you think you are putting on the bearings with the two adjusters?

a_reyes1014

iTrader: (1)

iwill let you know now im going to set it now

a_reyes1014

iTrader: (1)

ok my preload is at .0011" and my backlash is at .0010". how does that sound?