I just swapt to 3.73's and the ABS brakes arn't working, and the ABS INOP light is on. The shop that did will fix it, but the shop is an hour away and I work all day so I don't have time to take it and leave the car with them. Does anyone have any idea what could be causeing this and can I fix it? I have HPP3 and set it to 3.73 and 25.25" tall tire.

 

Not to change the subject on you but are you running the HPP3 Power Tuning? I am getting ready to put Jet Hot L.T.'s on and was wondering if I will have to remove my HPP3 Powert Tuning.

Wish I could help about your brakes. But I am curious too since my next mod after my headers are 3.73's.

 

did you check all ABS related fuses?

Do you have traction control? if not maybe they messed up the sensor on the housing, or the exciter ring on the diff...

 

Take a look at the rear wheels, inside, behind the rotors. The ABS sensors were probably unplugged during the install.

 

No I'm not running the power tuning but I have a ported maf so its running alittle lean already. But you can leave the power tuning on yours. the only way to tell if it helps or hurts your performance if you get it on a dyno it all depends on the other mods you have someone on this board can give you a beter explination than me----start a new tread. I'm also about to get a wet shot of NX, and you don't want it running lean with nitrous,
Thanx everyone I'm about to go and check everything closelly.

 

Oh, petegz28 good luck on the install its not hard at all it will probably take you a couple of hours. you'll love'em.

 

I checked all the fuses and their good. All the lines to the brakes seem to be good. Where exactlly is the wire or line to the abs sensor located? is it a line with oil or an electrical wire?

 

if you have traction control, there is one sensor on each brake backing plate. If you dont have traction control, the sensor shoudl be on the top of the diff housing somewhere (i havent ever looked at a no trac control car, so I cant be any more specific than that, sorry)

 

I had a similiar experience when changing gears as well.

I went from a 2.73 to 3.42.........
GM did the swap, but my ABS inop light was on. After doing some checking around, turns out the ABS reluctor needed to be changed as well. When you go from a 2 series carrier to a 3 series carrier you will also need the correct ABS reluctor. After talking to SLP i got the right reluctor and worked great!!

Kevin

 

I just did a 2.73 ---> 3.73 swap myself on Saturday!

My car does NOT have trac-control, so the speed sensor is located on the top of the diff housing (your's should be the same unless you've got trac-control). If the shop disconnected the wire to that sensor for some reason, they probably left it unplugged, or they may have just disturbed the wire in the process?! My ABS is still functioning normally, and I've got HPP3 as well (3.73's and 25.25" tires). It may be a little hard to see, but like I said, the wires are right on top of the gear housing. Aside from fuses, etc., that you've already checked, that's all I can think of?

Good luck sorting it out! Hope you like your 3.73's!! I know I love mine!!! (except the new traction issues!!!! ).

 

I love the 3.73's, but I don't want to get to reckless because of the abs issue. kevin97z28, when you say reluctor is that the ring that they had to switch inside the diff.? or am I way off. Explain it to me alittle better. Capn Pete, what size tires are you running that you set the HPP3 at 25.25" high. I have 285-35-18 nitto's and I have it set all the way to 26" and its running about 2 mph over at 70. So my friend was going 70 and I was at 72.

 

Yes MARSTAUT basically on my 97 there was a sensor that sat
atop of my diff. and it "read" a reluctor inside the rear diff. It was attached to the gear carrier. The problem came about because i went from a 2.73 to 3.42 GM just used my old reluctor from my 2 series carrier. Needless to say it wasn't the correct reluctor ring. the sensor that sits on top of diff. wasn't picking up a reading from the reluctor which in turn made my ABS Inop light come on. After getting a larger/correct reluctor it worked great!Maybe this may help some.
Kevin

 

I've got the stock 245/50/16's, and when I measured them, it got something around 25-1/4" to 25-3/8", so I went with 25.25", but maybe I should bump it up to 25.5", because according to this tire calculator, 245/50/16's are 25.6"?

So have you got your ABS issue figured out yet? Do you know if they changed the whole carrier like "kevin97z28" had, or have you checked to see if the wires aren't connected or something? All I did for my conversion was buy gears that were intended for a 2-series carrier, so the ring gear is thicker, but everything else is stock and still works normal.

 

Ya I put in a heavy duty Eaton posi carrier with my gears, and I checked all the wires. I believe I have the same problem as kevin97z28. It has to be the reluctor, I'm fixing to call the mechanic who did the install and check if he used the right reluctor. thanks for all your help.... I like that tire calculator