How can you tell 4 Ch vs. 3 Channel ABS rear end
11-23-2006, 07:04 AM
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How can you tell 4 Ch vs. 3 Channel ABS rear end I understand 4ch is used on cars with TCS. If a 3ch and 4ch rear end are setting on the ground, how can you tell which one is 4 channel ABS.
What are the mechanical differences?
Thanks and Happy Holidays.
What are the mechanical differences?
Thanks and Happy Holidays.
11-23-2006, 07:51 AM
#2
A 3 channel rear will have the ABS sensor sitting on top of the pumpkin (the reluctor gear is internal on those). A 4 channel rear will have the sensors at the end of each axle, and you'll be able to see the reluctor gear on the axles themselves (they are NOT internal).
11-23-2006, 03:26 PM
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That's kind of what I thought but here are pictures of a 4 channel with what looks like a reluctor gear inside AND on the ends of the axles. Help me understand this please. I've heard there is some kind of ABS gear inside the diff are but I don't understand what/why anything would need to be inside the rear end.
4 Channel pictures
Thanks.
4 Channel pictures
Thanks.
11-23-2006, 08:17 PM
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is there a 3-channel sensor on top of the pumpkin like meentss02 said, a black one with one screw affixing it thru the housing? I dont see one from the pictures
Could be one of two things
1. It is a 4 channel and GM assembles the posi's prior to knowing which rear its going in (3 channel or 4) and they just put reluctor rings on all of the posi units prior to assembly -- if it does NOT have the black sensor then this may be the reason.
2. It is a 3 channel rear with axles from a 4 channel, in that case there WOULD be a black sensor.
or it was put together with spare parts....
i didnt see the speed sensors for a 4 channel in the picture eaither, unless u are just using the ones on the car.
Could be one of two things
1. It is a 4 channel and GM assembles the posi's prior to knowing which rear its going in (3 channel or 4) and they just put reluctor rings on all of the posi units prior to assembly -- if it does NOT have the black sensor then this may be the reason.
2. It is a 3 channel rear with axles from a 4 channel, in that case there WOULD be a black sensor.
or it was put together with spare parts....
i didnt see the speed sensors for a 4 channel in the picture eaither, unless u are just using the ones on the car.
12-15-2006, 11:51 AM
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To me, that rear looks like a 3 channel that the guy has 4-channel axles in. I could damn near swear to it that my rear does not have a reluctor ring inside the pumpkin (it is a 4-channel).
You are right, I have a 4 channel axle and there is no reluctor ring inside the the diff (Pumpkin).
I have just fitted an Aliuminium cover so I just changed the oil as well.
