Trac Off/ABS Light and Continuous Low Trac Light [Archive] - GrandAmGT.com Forum

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Grreen99GT
03-11-2009, 07:13 PM
Alright, I know this has been covered countless times, but I am still a little wary on if I have a bad hub assembly. My car over the past few days has been flashing the Low Trac light continuously and every now and then the ABS and Trac Off light come on. Those lights stay on until I turn the car off and are gone when I turn the car back on. After everything I have read I assume that my hub assembly is bad so I would like to know if I made the correct diagnosis and if these would work as a replacement:

http://cgi.ebay.com/ebaymotors/2-Bearing-Hub-Assembly-Pontiac-Grand-Am-1999-2005_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c66Q3a 2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q 3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZite m290287193387QQitemZ290287193387QQptZMotorsQ5fCarQ 5fTruckQ5fPartsQ5fAccessories#ebayphotohosting

Thanks for all the help. My car is a 1999 by the way if that helps.

lone_wolf025
03-11-2009, 07:27 PM
Those might work, but personally I'm funny about buying off brand parts off of ebay.

vd5505
03-11-2009, 07:53 PM
Do you have a check engine light at all? even if you dont take it to AutoZone and have them scan it, i bet you have a bad ABS sensor

vd5505
03-11-2009, 07:54 PM
i ment the wiring to it sorry

Grreen99GT
03-11-2009, 08:03 PM
no the check engine light is not on

DefaZe
03-11-2009, 10:25 PM
Yea all the sudden my SVS, ABS, and Trac off lights are on. They turn on when I start my car, and stay on as long as the car is on. This started a week ago.

2000 GT Coupe
03-11-2009, 10:28 PM
mine would turn on after hitting a bump, or backing up, or just at random times, I replaced the drivers side one, found the bearing in very bad shape, I bought one for the right side, have not gotten to getting it put in.

lone_wolf025
03-11-2009, 11:03 PM
Do you have a check engine light at all? even if you dont take it to AutoZone and have them scan it, i bet you have a bad ABS sensor

He wouldn't get a SES light for the bad sensor, but likely that's what it is. Seeing as how the sensor is part of the hub assbly you gotta replace the whole thing. It is possible that the wiring is just bad, but most of the time its a bad hub. Just gotta inspect/test each wheel setup to see which is bad.

AaronGTR
03-12-2009, 06:58 PM
Do you have a check engine light at all? even if you dont take it to AutoZone and have them scan it, i bet you have a bad ABS sensor

There is no such thing as an ABS sensor. There are wheel speed sensors that are located in each hub, and those send a signal to the ABS computer which controls the ABS and the traction control. Usually those are responsible for the ABS/trac off/low trac lights coming on. They will not cause the check engine light to come on though. It's not an engine related issue. ABS codes go to the body control module not the powertrain module, and they will cause the service vehicle (SVS) light to come on.

DefaZe
03-12-2009, 09:24 PM
So Aaron if I have my ABS, SVS, and Trac Off lights on, what do you think is the problem. This just started recently after crashing into lots of snow.

AznGA
03-12-2009, 10:08 PM
Check the harness plug by the hub. They can corrode over time. You probably do not have to get 2 right now. Chances are only one is bad at the moment.

DefaZe
03-12-2009, 10:46 PM
I just take the wheels off and then check for bad wires?

AznGA
03-13-2009, 11:43 AM
Yea, look down behind the rotor. You should see a plug. Check that.

AaronGTR
03-13-2009, 05:26 PM
Yeah, the wires for the wheel speed sensors are in some small plastic wire loom that runs along the top of the front suspension arms and in the channel of one of the rear arms. Jack the car up and look for any signs of damage to those wires. Follow them to the plugs and the wire leads going into the hubs and make sure they are plugged in and none of the wires are damaged.

If they are all ok, then it's probably a bad sensor in one of the hubs themselves, and it will have to be replaced.

DefaZe
03-13-2009, 05:37 PM
How much, and where would I get one of these? And do you mean I have to replace the whole hub?

vd5505
03-14-2009, 07:17 AM
There is no such thing as an ABS sensor. There are wheel speed sensors that are located in each hub, and those send a signal to the ABS computer which controls the ABS and the traction control. Usually those are responsible for the ABS/trac off/low trac lights coming on. They will not cause the check engine light to come on though. It's not an engine related issue. ABS codes go to the body control module not the powertrain module, and they will cause the service vehicle (SVS) light to come on.

Yea i know its not called a ABS sensor but when you go to the parts store thats what they are under, i have a 2 year degree in CAT diesel and have work at our own high performance shop since i was a little boy, you dont have to be little me and go in depth about how there is "no" such thing as an ABS sensor

AaronGTR
03-14-2009, 10:39 AM
How much, and where would I get one of these? And do you mean I have to replace the whole hub?

Yes, you have to replace the entire wheel bearing and hub. It comes as an assembly with a new sensor built in. $146 for a new OEM one from gmpartsdirect.com. Your local auto parts store should have aftermarket replacements for $99-140 range.

Yea i know its not called a ABS sensor but when you go to the parts store thats what they are under, i have a 2 year degree in CAT diesel and have work at our own high performance shop since i was a little boy, you dont have to be little me and go in depth about how there is "no" such thing as an ABS sensor

Thats not what it's under at any parts stores I've ever been too, and it's not whats it's called in the factory manual. I wasn't trying to belittle you :rolleyes: but if you know what it's called, then call it by it's proper name and people won't think you don't know what it is.

tenspeed
03-14-2009, 11:12 AM
I just take the wheels off and then check for bad wires?

If you have ramps, you don't have to take the wheels off.

The connectors are on the bottom. Take them apart and plug them back in a few times. Put a dielectric grease on them. Sometimes the connectors get corroded and give the same symptoms.

If you do replace a hub, get a new silver nut to replace the black OEM one. It requires less torque to install.

Grreen99GT
03-16-2009, 09:33 PM
So should I steer clear of the ebay hub assemblies? i guess what i am asking is, if you were in the same situation would you buy from:

A) Ebay (cheap, aftermarket)
B) Auto Parts Store (still cheap, aftermarket)
C) GMPartsdirect.com (OEM, little more expensive)

ryanbgb22
03-16-2009, 09:38 PM
I'd assume that the autoparts store, and the ebay are similiar quality. I would probably just go with the autoparts store so I don't have to deal with waiting for delievery. Its not like the oem hubs are super reliable anyway.

tenspeed
03-17-2009, 10:13 AM
I have two ebay hubs - they were around $75 each. When I installed them, I coated all the surfaces with anti-seize so if they crap out, I don't have to fight to get them out.

Changing them in the driveway is not hard if your have the big socket for the axle nut. It's three bolts and a nut further in from changing rotors.

Many of the OEM hubs/ speed sensors fail so I wouldn't pay the big bucks for them.

vd5505
03-18-2009, 02:54 PM
There is no such thing as an ABS sensor. There are wheel speed sensors that are located in each hub.

Here are just a couple stores i found that do still call them ABS Sensors, and dont be to confused cause some manufacturers have different ABS systems and there are actual ABS Sensors

http://k-mansparts.com/items/f-150/brakes/ford-f-150-rear-abs-sensor-1990-to-2003-motorcraft-dy1123-detail.htm

http://www.bavauto.com/fland.asp?part=34%2052%201%20163%20027&utm_medium=feed&utm_campaign=googlebase&utm_source=34%2052%201%20163%20027

AaronGTR
03-18-2009, 04:06 PM
Here are just a couple stores i found that do still call them ABS Sensors, and dont be to confused cause some manufacturers have different ABS systems and there are actual ABS Sensors

http://k-mansparts.com/items/f-150/brakes/ford-f-150-rear-abs-sensor-1990-to-2003-motorcraft-dy1123-detail.htm

http://www.bavauto.com/fland.asp?part=34%2052%201%20163%20027&utm_medium=feed&utm_campaign=googlebase&utm_source=34%2052%201%20163%20027

Weeeeell we aren't talking about F150's or BMW's here, now are we. This is a grand am forum and we are talking about grand ams... and on a grand am there is no such thing as an ABS sensor... which is why I said it. So I guess that's the only thing that matters and your links were totally irrelevant to this discussion...

Grreen99GT
04-08-2009, 09:36 AM
Alright, well I checked the wires today and they still look really good. So I am figuring it is time to replace the hub assemblies. I ended up buying new ones from the auto parts store and then I went to dealerships to get the new nut to hold it on. Is this what the new nut should look like? I hope so because I had to drive to 3 different dealerships to find 2 of these.

http://pic60.picturetrail.com/VOL1747/8683765/18965579/360821447.jpg

By next week I should have these installed, I will let you guys know how it goes.

AaronGTR
04-08-2009, 04:32 PM
Is that the axle nut? You have to take the axle nut off to get the axle out of the wheel bearing, and then there should just be three bolts that hold it in the hub. You shouldn't have to replace any of the fasteners though, they can all be re-used. Only have to replace the bearing itself with the wheel speed sensor built into it.

2000 GT Coupe
04-08-2009, 07:11 PM
Is that the axle nut? You have to take the axle nut off to get the axle out of the wheel bearing, and then there should just be three bolts that hold it in the hub. You shouldn't have to replace any of the fasteners though, they can all be re-used. Only have to replace the bearing itself with the wheel speed sensor built into it.

The new style Axle nuts tend to not chew up the bearings as much, they use 180 pounds of torqe instead of the 200+
And yes those look like the new style nuts, I bought timkin wheel bearing and it came with the new nut.

Grreen99GT
04-08-2009, 07:49 PM
Is that the axle nut? You have to take the axle nut off to get the axle out of the wheel bearing, and then there should just be three bolts that hold it in the hub. You shouldn't have to replace any of the fasteners though, they can all be re-used. Only have to replace the bearing itself with the wheel speed sensor built into it.

yea its the axle nut. i will be reusing the 3 other bolts, but i heard that the main axle bolt needs to be replaced with this kind.

AaronGTR
04-09-2009, 05:02 AM
That's weird. Never heard anything about an axle nut chewing up a wheel bearing... don't really see how a different nut would make any difference either. I've always just re-used mine. I'm still on my original wheel bearings on this car though too. I've just had the axles out.

Grreen99GT
04-09-2009, 06:26 AM
That's weird. Never heard anything about an axle nut chewing up a wheel bearing... don't really see how a different nut would make any difference either. I've always just re-used mine. I'm still on my original wheel bearings on this car though too. I've just had the axles out.

The reason is because the original axle nuts were torqued to a higher pressure (like 250 ft/lbs) and the new ones are torqued to (170 ft/lbs) and that decrease in pressure makes the bearings last longer.

AaronGTR
04-10-2009, 05:32 AM
The reason is because the original axle nuts were torqued to a higher pressure (like 250 ft/lbs) and the new ones are torqued to (170 ft/lbs) and that decrease in pressure makes the bearings last longer.


Well yeah, but that doesn't really explain much. I mean, both axle nuts seat on the same spot, but if one requires more torque to hold the axle in the bearing then how does the other one need less? It doesn't make sense. What did they change on the nut that could make it require less torque than the old one and stay tight and keep the axle in?

It doesn't really make much sense to say that less torque makes the bearing last longer either. The nut isn't pulling in or out on the bearing. It's pulling the axle into the bearing until it's bottomed out on the other side so it's really just clamping on the bearings inner race. Any pushing or pulling on it would be exerted by in and out movement of the axle itself due to suspension movement. It doesn't really make sense to say less axle nut torque will make the bearing last longer.

Grreen99GT
04-10-2009, 07:20 AM
lol well i don't know then. i am just going by what i heard on these forums, but we know these people can be wrong lol

SSRacer
04-10-2009, 07:45 AM
mine would turn on after hitting a bump, or backing up, or just at random times, I replaced the drivers side one, found the bearing in very bad shape, I bought one for the right side, have not gotten to getting it put in.

Mine do the exact same thing. Also have a nice vibration. I need new tires too, so I don't know if that is from the tires or the hub. Guess I'll get new tires first then if that keeps up replace the hub. The drivers side is original with almost 95K on it now, the passengers side I replaced a few years ago after my mom broke my steering knuckle

geoph1986
04-17-2009, 11:00 AM
I would like to know if I made the correct diagnosis and if these would work as a replacement:

http://cgi.ebay.com/ebaymotors/2-Bearing-Hub-Assembly-Pontiac-Grand-Am-1999-2005_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c66Q3a 2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q 3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZite m290287193387QQitemZ290287193387QQptZMotorsQ5fCarQ 5fTruckQ5fPartsQ5fAccessories#ebayphotohosting

I ordered the exact same hubs, from the same seller. Shipping is pretty quick, I had them a week after PayPal was cleared. I am installing them this weekend and I'll let you know how they are. The brand name of them is CBK, which is the same generic, made in China brand I would have purchased from my local parts store for about $100 a side. Also, the ebay ones have a 1 yr warranty and the ones I could get locally only have a 6 month one.

geoph1986
04-25-2009, 04:57 PM
A little update. Those ebay hubs worked out good for me, perfect fit, noise is gone. I still have the ABS, SVS, and TRAC lights on, but that's due to a faulty plug on the cars harness, not the hubs.

SSRacer
04-26-2009, 05:29 PM
I got my tires and no more vibration or noise, so I need to look into a wiring issue too.

99PGAGT1
02-22-2010, 04:30 PM
I know this thread is a bit old but no sense in starting a new thread for a simple question.

Ive got a 99 Gt, and upon startup the low trac light comes on and goes off randomly and then the ABS and Trac Off light light up and stay on. No SVS or SES lights. I replaced the passenger side hub last april and the driver side today and the lights are still there. Will a bad rear hub cause these same symptoms? I would think that the Trac system would only apply to the drive wheels...? These lights are driving me crazy so any help is greatly appreciated.

AaronGTR
02-22-2010, 07:00 PM
There are wheel speed sensors in every hub, so yes a bad rear one could cause this too. The traction control and ABS systems work be reading the difference in wheel speed from the front to the back wheels, so it doesn't matter if it's the drive wheels or not. If one of the sensors is bad, those systems can't work.

It might not be the hub either though. There could always be a short in the wiring. Check all the wiring coming from the hubs under the car and make sure all the connectors are in good shape too.