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1996 Fleetwood Brougham w/Impala SS 3.73 Rear Suspension

1705 Views 4 Replies 3 Participants Last post by  96 Black
New to the Cadillac family. After warming up on a hot day, the car will intermittently hesitate when cruising or accelerating up a mild hill. I occasionally get an ABS and Traction Control light stuck on while driving. The error on the panel will reset after turning off the car, but still intermittently will hesitate. Cold start and drive it's OK. I finally searched and figured out how to get the error code out of the climate control. 04-135=Left Rear Sensor Error. Ohmed out all of the sensors on a hot day during fault mode. LF=1238 RF=1207 RR=1203 LR=1193. Back to the ABS module all 4 channels ohmed out to ~ 3.5 Meg ohm. Both rear sensors were pretty dirty with lots of metal shavings. Cleaned them up. Testing in progress.
Both ABS sensors have a long probe sticking out over the cog wheel. Will the front ABS sensors work in the back 3.73 w/disk brakes differential?
I will try to post some pictures.

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Welcome. One stutter up a grade could be associated with the converter lockup disengaging. I would infrequently get a momentary chuggle up a grade until the tranny remembered to kick out. If your ABS/TC fault is intermittent then do your testing with someone else wiggling the wires. The rears take a lot of abuse from debris/elements. Running staggereds with too large a delta will cause ABS to fault.

[QUOTE: Will the front ABS sensors work in the back 3.73 w/disk brakes differential?]
Wording not clear.
If this rear is the original one or came out of another FWB then we're still fine. If this rear is from a B- body then it won't work. The latter may be a different width than the Cady's, and it will only have the 3-channel style ABS reluctor in the pinion - not the ones at each wheel.
1.So, you're trying to install some spare new front sensors you have into the rear? Answer: IDK. But you may need to mod the backing plates for orienting the mounts.
2.You're asking about whether the Bosch 4-channel system would care what gears the car has? Answer: I don't see why it matters. Tow Package FWBs get 3.46 and 3.73 is not that different.
Unless you can find rear disks that are 4 wheel ABS compatible, you can not make it work.

The gear ratio makes no difference, unless you have the 3 channel ABS. A 4 channel system reads the wheel speed of each wheel, and if the tires are all the same diameter, they will all read the same. Your only issue will be the computer reading the output from the VSS, and translating it to speed in the trans shifting and speedometer/odometer.
Differential unknown

Thank for the feedback. The differential has Thunder Racing written on the cover. It has two screws with lock nuts on the back plate, and I read these are preloads of some type so when there is a heavy load, like popping a wheely, these screws keep the guts from coming apart, so I read it was to compete the Ford bullet proof 9 inch rear. The paperwork which came with the car said 3.73 Eaton LSD with reluctor kit. Thunder Racing has since gone out of business.

The previous owner said the Impala SS suspension was installed with Bilsteens all around, but the Thunder Racing Diff is, I don't know.

The ABS sensors are in each wheel, and they have the same white connectors and sensor heads like the front ones. I looked at the Impala SS rear end, and it has only one sensor on the pinion.

I found the LR sensor 7mm screw kind of loose. I ended pulling all 4 sensors and cleaning them and snugging them back down.

Test drove it today, and what a difference. No more occasional hesitation and it shifts smoothly up and down. I think it was never shifting to the higher gears? I was use to the hesitation thinking it was AC kicking in and out, or torque converter lock up on the freeway?

Only on a hot day did it fault the ABS/Traction Control and produce an error code. Led me right to that loose LR sensor, which I now believe was the root cause. Following the code and putting eyes on it won the day. I was ready to do a frickin' valve job!

Thanks again for your suggestions.
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I ended pulling all 4 sensors and cleaning them and snugging them back down.

I'm surprised you got any of the sensors out intact at all! They 'weld' themselves into the opening from the magnet attracting metal shavings and then rusting them in.
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