Red98TransAm

I may have an opportunity to buy a complete rear for my 98 T/A but it does not have the traction control my car has. I really want a spare so if I decide to change gears, or break the original rear at the track, I can swap out and still drive the car. What if I decide to change gears and install it in the car for racing and save my original rear, will it work? Can I tune out the TCS light with EFI Live if I do install it?

TRex

iTrader: (3)

You can make it work in your car, you will just need to either put your backing plates and axles on that axle housing (they have the necessary TCS sensors and reluctor rings) or get a second set of backing plates, sensors, reluctor rings, and TCS axles or axle adaptors to put on that axle.

I don't know what you are going to pay, but I have seen complete TCS axles for $300-350. I don't think there really is a significant value difference between a complete TCS rear and a complete non-TCS rear.

Red98TransAm

My real interest is in the backing plates and hardware as I already have a spare 3.23 TCS rear. The problem is that the "yards" want $225 or more for just the backing plates, used (and usually bad) rotors and calipers. This guy will sell his non TCS rear for $150 with everything. I just want to save time on the "re install" of a rear by not having to pull axles and such. I forgot one other thing on this purchase, the guy lives only 8 miles from me so I don't have shipping to deal with, but I surely don't need another rear sitting around.

TRex

iTrader: (3)

The problem is that the non-tcs rear will not have abs or tcs if you install it in your car.

I've never seen a non-TCS set of caliper brackets and backing plates, so I don't know if they have the material in the spot where the sensor goes. If they do, and it is just a blank without the hole, you might be able to convert it easily.

Can you take a pic of the non-tcs rear backing plate and caliper bracket (housing side, not rotor side) and post it, I will be able to compare it with mine then.

mike s.

iTrader: (2)

So, the housings will interchange as long as you swap backing plates, its related hardware, and the axles? I want to do the opposite of red98transam.

TRex

iTrader: (3)

It is a little harder to go the other direction, because if you want to use a tcs rear on non-tcs car, there is no provision for the abs sensor in the top of the housing.

To keep the abs with a tcs housing you need to swap your diff with the reluctor ring into the housing, then drill holes in it for your abs sensor, and tap one of them for the retaining bolt. You can use your existing non-tcs rear for reference as to where to locate the holes.

mike s.

iTrader: (2)

Screw that, I will get a non TCS rearend, I have found a few stockers w/o TCS for the same price. I have 2.73s in my Z, I want to get a whole housing with 3.23s for an easy and cheap upgrade.

TRex

iTrader: (3)

Look for one out of an M6 car and you will get 3:42's

mike s.

iTrader: (2)

Thanks TRex, might as well get the most gear for my money.

Big Z

iTrader: (6)

So if I swapped in a 3 channel rear into my tcs equipped car, as long as i swapped the backing plates and axles I'd be fine? The axles in my rear are the only things that are ok, all the bearings nad the diff are shot! I wouldnt have to mess with the diff at all? Thanks!

TRex

iTrader: (3)

You got it !

JasonWW

iTrader: (2)

I'm interested in this also. Has anyone on this forum put a 3 channel rear into their TCS car by swapping the endplates and axles?

I would hate to get that far into the swap only to find out the endplates won't interchange or the axles won't fit.

phantomzer0

iTrader: (17)

im actually half way done with this on the firebird[4 channel]. so far, i know i have to change the brackets over for the calipers and ebrake. i still have to take off the shocks and lcas on the old rear to get it off, nighttime came faster than i expected . the new rear is off of a 99 formula [3 channel], i dont know anything else about it other than it had low miles. ill be finished tomarrow hopefully around noon, so ill update on how it went.

btw: did formulas come with posi as a stock feature?

JasonWW

iTrader: (2)

I just put a 3 channel rear in my 4 channel car yesterday. Everything went smooth. I swapped the endplates and axles. The C-clips were the same. My old rear was a Torsen, my newer 3 channel was an Auburn. Still, the axles were the same except for the ABS rings on the end.

The differences were that the rear cover from the 4 channel or the MR Gasket chrome cover would not fit as the xtrat ABS ring around the ring gear sticks out further. I had to reuse the 3 channel rear cover. Even it just barely fit. It had some light scratches from the ABS ring teeth. I hammered on it a little just to give it somemore clearance and then painted it.

Another small difference is that the 3 channel rear does not have a small tab on the driverside tube to hold the plastic clip that holds the ABS wire. No big deal as I zip tied it to the brake line.
Also there is a metal tab that hold wires on the top of the differetial. That location is being used by the sensor so I just left it loose. It shouldn't cause any problem. I might zip tie it down later.

Other than those tiny differences, everything was the same. My ABS is working and if it works, the traction control should work as well. I haven't tested it as I keep the TCS fuse out, but I'm sure it works as well.

I really don't see anyone putting a 4 channel rear into a 3 channel car as there is no way to add a ABS ring gear to the center section.

JasonWW

iTrader: (2)

Actually, the retaining bolt hole is already there as well as the boss for the sensor hole. You WILL have to drill the sensor hole out.

phantomzer0

iTrader: (17)

i finished the swap on the firebird today. everything seemed to work out ok, but i did loose my abs and tcs. no big deal i suppose. i plugged the sensor back into the wiring harness just to keep the lights from going off on my dashboard. other than that, everything went smooth.

JasonWW

iTrader: (2)

What is the problem with your swap?
Did you re-use the 4 channel axles and backing plates?

phantomzer0

iTrader: (17)

yes sir, the old differential was open and had the tcs and abs gears inside, the new one does not. the new rear does not have the hole on the top of the pumpkin for the tcs module to slip into. otherwise, i have no idea how to get the tcs and abs working again.

JasonWW

iTrader: (2)

What your saying seems contradictory. earlier in the thread you said your Formula was a 4 channel meaning it has the 2 sensors on the axle ends and no sensor on the top of the center section. You said you were swapping in a 3 channel rear meaning it has the one sensor on top of the center section.
If you swapped the axles with the teeth on the ends as well as the backing plates with the sensors in them and left the center sensor unplugged, it should work.

Your new rear end should have all 3 sensors in it. The 2 on the ends that are plugged in and the center sensor that is not plugged in. You said "the new rear does not have the hole on the top of the pumpkin for the tcs module to slip into" yet all the 3 channels rear ends should.

Did you maybe mean you are putting a 4 channel rear into a 3 channel car? If not, them I'm missing some info.

phantomzer0

iTrader: (17)

hmm im sorry, i thought that if the car has tcs, it was a 4 chanel rear. the firebird has tcs, so therfore i said it was a 4 channel setup. the new rear does not have tcs, so i thought it was a 3 channel.