Rear Wiper Problems...

[junglejet]

I fixed this problem on my 99 mounty a few weeks ago. The actual cause of this problem is a defective wiper arm base. The two tabs at the base (washer hose runs between) it is not short enough. to fix the problem you will need to pull the arm all the way back and look at the base you will notice two tabs from the base of the wiper arm. if you look closely there is a notch this is where it the notches should have been cut but it was not so it causes the wiper arm not to sit properly on the glass causing the void. Simply take a pair of pliers and break both tabs off. most likely it will break from the base instead of the line this is ok way. good luck.

 

[Dave S]

I have good news and I have bad news.

First the bad news. While trying Joe's fix of grinding down the tabs I broke the wiper arm clean in half............ grumble grumble. So I went down to my local Ford dealer and ordered a new arm ($43 bucks )

Now the good news............after I put on the new arm, the blade now wipes the entire window without lifting! The only thing I can figure out is over time the arm becomes distorted somehow and even though bending the arm works for a little while the arm probably becomes too out of shape for bending to fix it.

Just thought you folks might want to know about this.

 

[nolimitssjca]

I guess grinding it down does work! (one way or another) LOL

 

[gijoecam]

There was a TSB on the issue a number of years ago. The TSB was to replace the 'bad' arm with a 'new design'... the new design had shorter fingers. They did that on mine, but it, too, eventually started missing the center of the window. The only thing I've been able to think of is that the motor mounting bracket may fatigue over time due to the spring pressure and possibly gravity, distorting and causing it to not work. Bending the arm only works to a point, but eventually the arm is bent so far that the ramp no longer makes contact with the finger and the wiper parks on the door (not good for paint). Since modifiying mine back in early '03, I haven't had an issue.

-Joe

 

[Dave S]

My theory is it has something to do with bending that occurs from opening and closing the liftgate. I think each time you slam the lift gate that arms distorts a little bit from the force of the liftgate closing. Slam it enough times and it is out of shape enough so that it no longer contacts the window. Interestingly enough, my old arm broke right on the casting. That's a pretty hefty casting so one has to wonder if the casting was the problem all along and maybe that's what was distorting.

BTW......a year or two ago I also removed the interior panel to check the mounting for the motor. Mine was a little bit loose so I tightened it up but it had no effect on the skipping problem.

 

[craigb3]

There was a TSB on the issue a number of years ago. The TSB was to replace the 'bad' arm with a 'new design'... the new design had shorter fingers. They did that on mine, but it, too, eventually started missing the center of the window. The only thing I've been able to think of is that the motor mounting bracket may fatigue over time due to the spring pressure and possibly gravity, distorting and causing it to not work. Bending the arm only works to a point, but eventually the arm is bent so far that the ramp no longer makes contact with the finger and the wiper parks on the door (not good for paint). Since modifiying mine back in early '03, I haven't had an issue.

-Joe

The x I just bought has this problem and the wiper sits tucked in under the glass, sitting right on the body. It caused two nice chunks of paint to be removed. So don't let it get to this point or you'll have body/paint damage.

 

[GeorgeR]

There is a little shelf for the arm to rest on, on my '96xlt

 

[gijoecam]

There is a little shelf for the arm to rest on, on my '96xlt

95-96 is different than the 97-01s.

 

[craigb3]

thay all have that "shelf" that was mentioned though. mine is caused by the arm being so bent out of shape.

 

[WhiteLimited]

So my stock blade works ok but I replaced it and now I am having these rear whipper problems...Is there another page were I can read up on the Mod? Or is this it?

 

[ExploringDC]

Seems many have seen this ('98 or so) "missing the glass" problem - but no mention of my finding so - here goes. After trying many things, I discovered that the inner deck "shell" is way too weak and bending where the motor fastens, and gets distorted with a pull on the strap for closing the hatch. The solution I used is two-fold - 1. Took a 3 and 1/2 foot 2x4 and stood it on the sill and against the weak inner metal, and hung my 175 lbs. on the hatch. 2. NEVER use the vinyl strap again to close the hatch - only reach to hatch edge and pull to close. (never had a weakness like this in my '91 or '94 - just have to remember not to pull the strap - I may cut it real short) Now working with a full wipe for over 2 years!

 

[storlied]

Makes sense.

 

[surfsup887]

my friends's X was doing that. we bent the arm until it wiped the whole window

 

[storlied]

How long did that fix work? And also, was it a 2nd gen?.. What year?

 

[gijoecam]

I use the pull strap every time I open the hatch. I once had the missing glass issue. I shortened the fingers on the rear wiper hinge joint to allow the arm to flex further. It's not missed a wipe since 2000.

If the inner tailgate panel was moving so much that it solely prevented the wiper from touching, the panel would have to be bent beyond recognition, with the trim being pulled away from the body by at least a few inches. Furthermore, my inner panel is not distorted at all. The more likely culprit is the motor bracket itself. There have been people here that have seen issues with the rubber bushing(s) failing, and the bracket itself getting bent (automatic car washes can do that).

The root cause, IMHO, is a wiper arm that does not flex far enough. In theory, if the arm was designed properly, the wiper motor should be able to be installed at up to a 30 degree angle in any direction with respect to the window and still allow the arm to flex enough that it makes contact with the glass. That's why I modified the arm and it hasn't been an issue with any of the 4 replacement wiper motors I've had in there... All four were not identical, but all four worked (until the motors died anyways...)

-Joe