I am planning on replacing my ABS module with one from a 02 firebird (I have a 98 z28). Both my car and the module that I bought were are non TCS. I am just curious if I will have to completely reprogram the ABS since maybe the gears in the cars are different, or if it will be a plug and play type deal.

thanks

 

if your car is a three channel (non-tcs), and the module are three channel than you should be good. The gear ratio setting needs to be changed in the PCM.

 

So will I need to change the setting in the PCM? I didn't mess with the rear end, but I didn't know since the cars had different final drive ratios if that will prematurely set off the abs

 

Or could I just keep my EBCM and bolt it up to the new BPMV? And would I need to install a new wave spring?? thanks

 

If the gear didn't change then you don't have to do anything

 

would the final drive ratio be different anywways since the v6 and ls1 tranny gears are different

 

ABS reads wheel sensors. It doesn't make a **** how many times the engine/trans has to turn to get the wheels moving. The only thing that is important is that all 4 wheels are turning the same speed. Or in non-TCS car, the ring gear (which is directly tied to wheel speed) is spinning the same speed as the front two wheels.

 

Took the words right of my mouth. Wheel sizes and gear ratio changes can cause the module to throw up an error. As long as the PCM (ABS doesn't care) is programmed with the correct overall tire diameter, and the correct ring gear ratio, you'll be fine. In fact there's a tolerance for slight discrepancy.

 

Just out of curiosity, dont know if all fbodies are like this or someone changed it in the past. We went to put an 02 ABS module in an 01, and the brake lines were different. On the 01 the two rear lines went together and one line came forward to the ABS module. On the 02 it had 2 lines come from the rear into the abs module.

 

okay that clarifies it then. Thanks guys. Ill have to contact the guy I bought the module off of and find out what ratio was in the Firebird he took the unit out of. It is a non-tcs (3 carrier), which my car is, but I'm pretty they came with 308s and 273s also.


Thanks for the info again.

 

I guess this unit came from a 02 ws6 with 342 gears so looks like ill have to reprogram or just use the bpmv

 

maybe not, I read lees last posr wrong, so basically as long as its a nontcs and I didn't change ratios I shouldn't have to mess with thd programming? since the abs gets the readings from the pcm?

 

No absolutely not. PCM controls the gauges for speed and odo. It doesn't have anything to do with ABS in that respect. Re-read my post. As long as the ABS/PCM sees all 3/4 sensors as turning the same speed then everything is go. Change the rear tire height only and you'll get an ABS disable light. Turn the rear wheels on a dyno, same thing. Changing the tune for "tire height" and/or gear ratio does nothing but change the speedo, odo and auto trans shift points. The ABS system is designed to run 4 equal sized tires and that cannot be deviated from. If you choose to run different size tires, you must live with no ABS, as it cannot be altered for different tire sizes in the front to rear, side to side, or any individual tire.

 

01redssa4, thanks for the great info but I'm lost.

If I have a car (02) with the TCS and I want to run a set of 18" wheels in the rear and 17" wheels in the front I would get a ABS Disabled light on my dash ?

What if the sidewalls of the rear 18" we're shorter and matched the front 17" rim and tire height, would that keep from throwing a light ?

I am not a fan of this option but I don't want any lights on my dash illuminated. I hate the TCS illuminated light on when I switch it off, and really wish the car didn't have it at all, maybe I could unplug it behind the panel and remove the bulb in the dash cluster ?

 

Rim size makes no difference. Its the rolling length or circumference of the tire that matters. You ARE allowed a certain amount of error and the ABS will still function. However, deviate too much and its a no go. How much error I couldn't tell you bc I've never tried it, but I bet with a little digging you could find some examples that could steer you in the right direction.

 

And, I think the bulbs are tricky to remove, most remove the glass and black tape over them for simplicity.

 

Thanks, appreciate the help.