Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Taxi_Driver on 28 March 2007, 21:04:11

Title: What are those cogs on the rear diff for?
Post by: Taxi_Driver on 28 March 2007, 21:04:11

Noticed today.....when my omega was up in the air....a cog type wheel on either side of the rear diff.
I discovered a sensor on each one.....i asked one of the guys in the garage (The Boss is away)....his answer was ummmmm....abs sensor.....was he right??

Also why is one of them nicely rusty on the sensor edge and the other is nicely shiney?
I guess the sensor is rubbing on the wheel? should it be? Dunno  :-/

The side thats shiney has got an oil weep.....so apart from the edge thats shiney the rest of the cog is a bit 'damp' with oil.

Any ideas/help appreciated  :y

Title: Re: What are those cogs on the rear diff for?
Post by: hotel21 on 28 March 2007, 21:06:57

Its the ABS gubbins, TD.  Sensor picks up when one shaft stops rotating against the other and applies/reduces brakes accordingly.  Believe its also used by the traction control, but sit to be corrected...   ;D

Same thing also on front wheel bearing housing with sensor on the carrier to sense when wheel stops rotating.  Check the image on  this (http://cgi.ebay.co.uk/Vauxhall-Omega-Carlton-Senator-Front-Wheel-Bearing-Hub_W0QQitemZ180054654903QQcategoryZ10404QQrdZ1QQssPageNameZWD1VQQcmdZViewItem) item to see what I mean.

HtH

B

Title: Re: What are those cogs on the rear diff for?
Post by: Taxi_Driver on 28 March 2007, 21:11:50

Quote

Its the ABS gubbins, TD.  Sensor picks up when one shaft stops rotating against the other and applies/reduces brakes accordingly.  Beleive its also used by the traction control, but sit to be corrected...   ;D

HtH

B

Cheers Broocie,  :y

20yo mechanic type blokey was right then......i thought he was just guessing  ;D

I havent got TC.....so not that on mine  :y

Title: Re: What are those cogs on the rear diff for?
Post by: Auto Addict on 29 March 2007, 06:38:48

The cogs are there so your expert mechanic can get a cold chisel and a lump hammer, to check that the diff spins easily.....

Title: Re: What are those cogs on the rear diff for?
Post by: DaveL on 29 March 2007, 20:36:14

Quote

Also why is one of them nicely rusty on the sensor edge and the other is nicely shiney?
I guess the sensor is rubbing on the wheel? should it be? Dunno  :-/
The side thats shiney has got an oil weep.....so apart from the edge thats shiney the rest of the cog is a bit 'damp' with oil.

Any ideas/help appreciated  :y

There should be an air gap between the sensor and the toothed ring. If one of the sensors has been catching on the toothed ring then it could well be cream crackered. You may get an ABS fault light come up if this is so. :)
 8-)
DaveL

Title: Re: What are those cogs on the rear diff for?
Post by: Taxi_Driver on 29 March 2007, 21:44:36

Quote

Quote

Also why is one of them nicely rusty on the sensor edge and the other is nicely shiney?
I guess the sensor is rubbing on the wheel? should it be? Dunno  :-/
The side thats shiney has got an oil weep.....so apart from the edge thats shiney the rest of the cog is a bit 'damp' with oil.

Any ideas/help appreciated  :y

There should be an air gap between the sensor and the toothed ring. If one of the sensors has been catching on the toothed ring then it could well be cream crackered. You may get an ABS fault light come up if this is so. :)
 8-)
DaveL

Cheers......The ABS light isnt on at the moment, but i will know where to look if it does come on  :y