Front ABS Sensor Chewed Up Again!

[ERIC]

OK, Wrench Heads, I need some help here.

About a year ago, the dealer replaced (my cost) the front ABS sensors in my 96 XLT. They said it appeared the head of the left sensor was chewed up. To make a long story short (it would be best not to get me started on this) I am not gonna take it back to them, even tho I feel they screwed up the job.

I checked with the <fordpartsnetwork> and they can sell me the set of sensors for about $230. And the installation doesn't look at all hard from the Haynes manual.

However, I suspect there is some debris loose around the sensor ring. The question i have is, once the sensor has been removed, am I gonna be able to see into there and fish out any foreign matter? Or is there some way to clean out that space? If something is in there, it's surely gonna chew up the new sensor like it did the other two, so I need to get it out.

Anyone been there, done that?

 

[mrboyle]

The sensor is magnetic, so any metal shavings or particles will be attached to the sensor when you remove it. The rest you can wash away with brake cleaner.

 

[ERIC]

Mike,

I thought this was a closed system. If I just pull the sensor, and spray in brake cleaner, where does it go...is there an opening?

 

[mrboyle]

The hole for the sensor isn't a blind hole, it is open at the bottom so the cleaner will go stright through.

 

[ERIC]

Thanks, Mike.

 

[Ray Lobato]

Eric,
For less then $230.00 you can get the whole front bearing assembly (ONE SIDE ONLY)and the ABS sensor comes with the assembly.
I know because I just recently changed one. Your 96 can't be any diffenent than my 97. Check into that before you shell out that kind of money. The whole assembly is one piece and when my bearing went out, it tool the sensor and everything else. The 95+ models aren't like the 91-94's where everything is seperate.

 

[ERIC]

What's the deal, Ray? Ford makes a big deal about how you have to replace both sides' sensors even if only one needs it. I take it you just went for the one side tho...and it worked, no problem?

I keep hearing how the two sensors have to be "balanced" against each other. Is that just bull?

But, yeah, I think replacing the whole assembly might be a good idea. Apparently the exciter ring (or something) has eaten up two sensors in 14 months, so putting in a whole new assembly makes sense.

But what do you think about that "balancing the sensors" stuff?

 

[Ray Lobato]

Well, the parts guy did say that they recommend buying both sides, and if they were to do the work they would insist that both sides be installed, but he didn't think that it would be any big deal and sold me just one side anyway. IF you replace the whole hub assembly on one side, you will have to buy the grease seal and the housing(sorry don't know the technical name for it), they can print out the assembly and you can see it, it's between the CV and the steering knuckle(actually fits inside the steering knuckle). The 2 parts don't cost much, but If you don't want to have to take the steering knuckle apart to the replace the bearing seal then that housing has to be knocked out and it's better to just replace it then to try and reuse it. Be careful and pay attention to the direction of the seal, you don't want to put it in backwards and the picture doesn't help in showing you which way it goes.
I would also recommend that you buy new bolts, because I think I heard that you are not supposed to reuse the old ones. Hope this help.
Oh! One more thing. I don't see how they are going to balance the 2 sensors, since there is no adjustment for this. They are not sold in sets. They have them individually wraped in a box. I was going to buy one, but when I opened the hub assembly I found that it comes with a sensor.

 

[gbeck]

replacing hub assembly

Hi Ray,
I have the slow speed abs activation problem. I was going to replace the complete hub assembly like you. My local parts store has it for $145 with sensor installed. I have a '97 also. After you take out the three bolts that hold the hub on, does the hub just slide off the spindle? It's been awhile since I had mine apart but I thought that's the way it was. What seal and houding are you referring to? The new hub I looked at had the seal already in place.

Thanks,
Greg

 

[Ray Lobato]

Greg,
Yes when you unbolt the three bolts the hub assembly will come right out, but if you look at the steering knuckle, you will notice a plate like thingy (I know real technical jargon) stuck in the steering knuckle. On the other side of that is the grease seal and that gets press against the plate and the CV. There is a bearing on that grease seal that spins with the CV. It is there to keep any grease from the hub assembly from coming out or and dust, dirt, or water from getting into the hub assembly. You can not install that seal unless you take the steering knuckle off, because you can't get it around the spindle and the steering knuckle, unless you knock out that plate, put the seal through the steering knuckle and then put the plate back on. When I tried to putthe original plate back on, it was very loose, so I just went and got another one. I think they only cost 5 bucks. I hammered it back in and put the rest back together. I figure if you are going to replace the hub assembly, then you might as well do that seal also. When my bearing went out, it took that seal with it, so I had no choise but to replace it.

 

[ERIC]

Originally posted by Ray Lobato
Oh! One more thing. I don't see how they are going to balance the 2 sensors, since there is no adjustment for this. They are not sold in sets.

Ya know, I've been thinking about that very thing all day, and I agree...they are not sold in sets, so there is no way possible for a person to buy a "matched set." I think this "requirement" might be a case of over-engineering the specs. However, I fear the last sensors installed on my truck are aftermarket, and if that's the case, perhaps the OEM ones might not be exactly the same. Still, it's worth a shot as all I'd be out is having to replace the sensor on the other side. I figure I'll do the whole assembly on the driver's side tho since there is apparently some problem with it anyhow. Thanks for your help and guidance.

 

[Ray Lobato]

Well Eric,
There are some things I will trust the after market and some things I will trust Ford. The Ford hub assembly ran me about $175.00, which is about 35 bucks more than the aftermarket price. 35 bucks for piece of mind, is it worth it? You be the judge.

 

[ERIC]

Yeah, I'm gonna go the Ford route...and if there is a mismatch with the other sensor, then I'll just have to replace that side too. If the dealer had done this job correctly in the first place, I doubt if I'd be having to redo it now...which just proves your point, eh?

 

[gbeck]

Ray,
Thanks for the reply. A couple of more questions if you don't mind. Have you heard of anyone changing just the sensor to take care of the slow speed activation problem? Is there a locknut on the spindle that tightens down on the bearing, like most front hubs? If there is, what is the torque specs?

Thanks,
Greg

 

[Ray Lobato]

Hi Greg,
Yes there is a lock nut on the spindle, but I don't know what the torque is on it right off the bat. It is in the haynes or chiltons manual thought. There is also a torque spec on the 3 bolts for the assembly too.
I haven't heard of anyone changing the sensor on the assembly for a slow speed activation problem. Have you taken it out and looked at it to see if maybe it was dirty or something? Have you checked to see if the connections maybe aren't just hanging on be a thread? Have you cleaned the connectors on the other side?
Those are just some things I would look at before I would go out and spend some money on a new sensor.
If you have already done this, then I guess it wouldn't hurt to try a new one before you go to a mechanic.
Hope this helps.

 

[ERIC]

Originally posted by gbeck
Have you heard of anyone changing just the sensor to take care of the slow speed activation problem?

Yes. I did exactly that. And it IS a known problem...Ford has a TSB out on it. I don't recall the number since my wife cleaned out a bunch of "junk" papers, and all my records on my Explorer apparently qualified...jeez. Anyhow, the TSB covers a variety of tests to perform to determine if the ABS sensor is in fact the culprit, but from what I recall of it, it's almost a given that if your truck is doing this, replacing the sensors will cure it.

But, Greg, if I knew then what i know now, I would have had the assemblies replaced, rather than just the sensor because I now suspect the exciter ring or something in there is eating the head of the sensor. My dealer never suggested that! Of course, my dealer wasn't aware of the TSB, couldn't locate it when I gave them the number, and seemed offended when I walked in with a copy of it.

 

[gbeck]

Thanks Eric and Ray
No, I haven't taken the sensor out. I tore everything apart and got to it. I took out the bolt securing it. I turned it and gently try to remove it. It did not want to come out so I put things back together. I wasn't sure if it would go back in if I forced it out. I will probably try to remove it and see. My parts store is just down the street and I will make sure the assembly is in stock before starting. If I don't find anything obviously wrong I will probably go with the whole thing. Can't see buying a $100 sensor when I can replace everything for $150.
Thanks,
Greg

 

[Ray Lobato]

Greg, Eric,
Let me know how it turns out, and good luck.

 

[ERIC]

Originally posted by Ray Lobato
Eric,
Let me know how it turns out, and good luck.

Turned out to involve more problems than originally thought.

Even so, regarding replacing ABS sensors in pairs, the bottom line is: There is no reason to replace both sides of the ABS sensors if only one is bad.

I have now replaced the rear driver side sensor and the front driver side without replacing their paired sensors on the passenger sides. And that was all that was needed. Looks to me like the FMC directive that both sides must be replaced at the same time is (at the least) overengineering.

 

[Ray Lobato]

Hey Eric,
Did you replace the whole assembly or just the sensor on the front? Also what was the reason for replacing the rear sensor?