A $20 solution for the rear wiper motor "problem"

[acct21]

First, I want to give credit to Sonoraed for the idea -- although I found a post from a member named "stuart" (he hasn't posted since 2007) over on the old site from 2000 that was exceptionally prophetic.

http://www.ifsja.org/forums/vb/showthread.php?t=16824

Second, sorry for the poor write up. I was so mad after having a marine wiper motor recommendation go horribly wrong that I was scrambling to just get it done, and neglected to get really good pictures as I was doing it. This is my best attempt to reconstruct the build with all of the details...

So we all know how pathetic Chrysler's attempt at the 89-91 wiper motors was. The problem has been that working motors are non-existent, and if you could find a working one chances are it won't be working for long. We need a suitable replacement that is easy to source, easy to install, and works in the confines of the tiny space in the tailgate where the original motor sat.

The Durango has a suitable replacement. I know 100% that the motors from 1998-2000 will swap in perfectly. The motors will work from 2001-2003 as well, but there is a possible catch: I have seen some of the motors from these years missing the small black control box -- suggesting the continuous/pulse/park function is handled elsewhere in the vehicle's electronics. You need a motor with the "black box." More on that in a second.

You need to pull EVERYTHING off the donor vehicle. Just make sure the arm, mounting nut and all of the spacers/covers/gaskets are there before you start. If you are missing any of the components just look for another donor vehicle -- this is super easy to make work if you have everything, but probably not workable without some significant fabrication effort if you do not...

From the outside, pull the arm, dish-shaped spacer underneath the arm, and the motor mounting nut. As opposed to the mounting nut on the 89-91 GWs, you will not snap off the motor housing when you remove the mounting nut, so feel free to use a little elbow grease if needed to get it off. Then carefully pry/pop off the outer half of the tailgate gasket. You should now have everything off the outside of the vehicle. Here are some pictures of what you need to get. The wiper arm (and the little plastic trim piece/grommet) is not shown.



Then go inside the tailgate, and remove the large, cheap plastic trim panel. It is held on with a couple of screws and some trim panel grommets. The wiper motor will be right there, held on by two 10mm bolts. Pull the motor, making sure you get the inner tailgate gasket when you take the motor out of the tailgate. I cannot stress how important this one little piece is/will be. You might need to pry at it a bit, or go back outside and push it back through the hole. Just get it. Now trace the 4 wire harness past the plug, and get as much of it as you can. Cut it back at least 8-10" if possible. You'll now have both sides of the harness -- the part attached to the control box (black box) and a good length of it on the other side of the plug as well.

You'll now have all of the parts you need for the swap. Here is a picture of the motor you are looking for:



Now the mount for the motor needs to come off. Pull the two bolts mounting it to the motor, and priy off the little cable stay that is attached to the harness. The control box is also attached to the mount, and needs to come off. It 'clicks' into the mount and is held there by a little tab, but I couldn't get anything thin enough to push in there to try and release it. I just gently (but firmly) pried it off of the mount with a large flathead screwdriver at the point noted.



Now for the fun part -- cutting on your perfect tailgate. There's no way around this -- nobody is ever going to reproduce that original wiper motor, and nothing else on the planet will work and fit in that small hole. You have to make the decision now -- busted motor (or an empty hole, if the motor is gone) or perfect, working motor that will require a little fabrication. There's no going back after this!

[acct21]

Picked up the step drill bit at Harbor Freight. It looks to go from 1/4" to 1 3/8". You need to drill to the 1" size and then STOP. Check the fit of the inner tailgate gasket. If the little rim does not fit snugly through the hole (mine didn't), go one more step to 1 1/8" and check again. You want the inner rim of the gasket to just pop through the hole in the tailgate. It shouldn't be distorted (forced through), but you don't want a gap, either. Go slow and check frequently.

Now the motor goes in clocked differently than the original. The original was clocked at exactly 6 o'clock. The new motor sits at about 8 o'clock. As you sit in the back of your GW, looking up through the access panel hole, the left side of the Durango wiper motor gear box will clip the reinforcing channel to the left of the hole in the tailgate by about 3/4 of an inch. This will prevent the motor from sitting flush against the inside of the tailgate. This reinforcing channel needs to be trimmed back to allow the motor to go in. Credit to Sonoraed for the following picture, which shows exactly where you need to trim (angle grinder, sawzall, plasma torch, whatever works for you). You just need to take off the little tab shown in the photo. Go slow -- it's much easier to remove more than it is to put it back!



Once you have the fitment all sorted out, you have one final decision to make. You can either cut the pigtail off the original motor (if you still have it), or cut the plug off the harness in the tailgate. Either way you need to splice the GW tailgate wiring to the Durango motor. Each has four wires, and each wire has a corresponding location on the new motor.



There might be some different wire colors, but just remember: red/yellow seems to be universal on the GW harness for +12V, and black is ground. On the Durango, pink is universally +12V, and black is ground. The other two wires are continuous wipe and pulse wipe (for the washer). You might need to test to make sure you don't get these backwards.

I opted to cut the plug off the tailgate harness, as I think in the future if I need to swap in another Durango motor I can do so quickly; it will literally be plug-and-play at that point.

Now get everything test fit and snug up the motor mount nut (outside the tailgate) and make sure everything is seated and flush. Then you need to add a strap/brace between the motor and the tailgate. I re-used the mounting bolt on both the motor side and the GW side -- mounting the tailgate side of the strap to the bolt hole that originally held the OEM motor. Once the Durango motor is in place you will notice that the bolt holes for the motor and the tailgate mount are not in the same plane. I used a 90 degree 2X4 nailing brace from Lowe's/Home Depot -- carefully bending it until it was flush with the motor case and the original tailgate mount. I then re-used the 10mm motor mount bolt on the Durango motor side, and the original GW bolt for the tailgate mount. You can see from my installed pic that the strap is perpendicular to the axis of the motor rotation, so there won't/can't be any rotational movement of the motor. It is in there really solid.



Here is a pic from the outside -- You can see from the years of built up grime around the old bezel that the new mount fits nicely in the area where the old one occupied!



Sonoraed's finished product as well:



Only conceivable downside is that the Durango arm is about an inch longer than the stock 89-91 GW, so you can't use a 13" blade as before. I have an 11" on there now, but it looks like a 12" might clear the top of the glass as well. It wipes a great pattern as-is. I'm just happy to have a functioning wiper again!

[sonoraed]

Great write up and photos, I got the idea from Overland Jeeps up in Montana and someone told him a guy in Texas that restores Wagoneers was using the Durango motors, I just used a customers waggie to experiment with and it worked,just love seeing DIY's overcoming impossible problems like this for $20 bucks!

[acct21]

Well, without your photo of the finished product I would have never had the faith to drill a 1 1/8" hole in my tailgate -- so all of the credit is yours.

And I didn't mention the cost breakdown in the write up:
$12 Durango wiper motor and wiper arm from local pick-n-pull
$6 Step drill bit from Harbor Freight
$2 nailing strap (for the tailgate/motor brace) from Home Depot

I probably should change it to "A $29 solution" as you have to buy a new wiper blade -- that was $9 from the local parts house. Regardless, it works great, integrates with the original wiring/switches and looks stock -- with a nearly endless supply of spares if the motor ever goes bad. A solid upgrade.

[sonoraed]

I used the original wagoneer arm and enlarged the tapered mounting hole with a step drill (to use the longer blade) but your all durango install looks much cleaner, does the blade park and wiper arch seem to work ok?

[acct21]

Works perfectly. On/off, pulse wipe (using the rear washer momentary switch), park -- all just like the OEM motor. Unless you can instantly spot the difference between the external tailgate trim/spacers on the Durango and GW applications you wouldn't know it had been replaced.


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[jsinajeep]

Nice job by both of you guys and I put the write up where I can find it when I want it.

[Road Trip]

Thank you for taking the time to do the write up. I have been scratching my head on "how to" after driving a Yukon with a rear wiper for years, I knew I needed one.

Another questions for you both, since my tailgate didn't have the rear wiper, is there any other pitfall I need to be ready for when trying to do the new installation?

Thanks.

[acct21]

A few come to mind:

You have power and ground in the tailgate you can tap into, but obviously not the other wiring. With no washer you just need a simple on/off toggle switch that sends switched +12V (when 'on') from the switch to the tailgate. Hook those three wires up per the instructions and you'll have on/off/park -- just no pulse wipe for the washer.

In a GW that didn't come from the factory with a rear wiper there might not be a tapped hole in the tailgate window regulator to attach the motor to. You'd need to drill/tap a hole there yourself.

The non-factory wiper GW tailgate reinforcing panel might not be cut out where the hole for the wiper shaft is, like on the '89-'91 models. You would need to trim out enough for the wiper motor to fit in there.

Drill the hole in the right spot!


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[hhoope]

This post is brilliant! I had just given up on being able to keep my rear wiper on my '89 Wag. Using this post--thank you for the detailed pics-I have already pulled what I need from Durango and am ready to get started. For you guys that have completed this, since the blade will rest on the glass instead of the tailgate, how does the wiper blade "behave" when the window glass is rolled up and down?

[acct21]

Clock the Durango arm so that the end of the blade closest to the center is just touching the tailgate weatherstrip/glass wipe. The other end will only cock up about an inch on the glass -- which doesn't roll down all the way into the tailgate anyway.

On mine, using the Durango arm and an 11' generic blade, all but the last 2 inches touches only glass when the window is fully down. No issues whatsoever with it getting in the way rolling the window up.

If you are (or know) a super fabricator, pull the thin section of the arm out of the GW piece (held in by a rivet and the crimped-over base piece) and graft it onto the base of the Durango arm. That way you will have the factory 'bend' to the arm and it should be able to be clocked perfectly flat like the original. You could also put the Durango arm in a vise, heat it up with a torch and put a little more bend into it to match the bend on the GW arm.


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[hhoope]

Perfect. Don't have the GW arm to graft, but was considering sectioning the Durango arm to shorten it or the bending route you suggest.
Thanks again for posting this. Huge help.

[acct21]

Just FYI -- I have an old (broken) GW arm, and a bunch of Durango arms. Mine looks (and works) so well as-is that I haven't even bothered to try and tinker with it. You'll see what I mean when you get it installed -- it is so close to stock that you will be inclined to just leave it alone.

[JoeMan89]

Truly a great write-up. So awesome that it inspired me to go out the boneyard today and get all the parts. I have yet to dive into the install process and before i do, i have a few questions.

Where did you end up re-locating the control box to?

Is it common to have excessive delay between cycles on the motor?
I quickly wired up the durango motor to see if the part was good and noticed the delay seemed excessive. Could i have two wires crossed?

[acct21]

I just zip-tied the control box out of the way, using really long industrial-strength zip ties.

My motor completely cycles at just under 1 cycle/second. That's whether I hit the washer or the actual wipe setting on the switch. You might try switching the orange and violet wires and see if that solves it. Otherwise you might have a bad control box.

[stevemorgan]

Great thread it worked perfectly I also modified the OE wiper arm and once in place it worked perfectly

[chrisrkirby]

I can't see these pictures and REALLY need to. Any suggestions? Thx

[chrisrkirby]

I can't see these pictures and REALLY need to. Any suggestions? Thx

[will e]

Welcome to the board. If you are using Chrome you can get an add in that will go around the photobuck block.

[Jdm1990gw]

I did the conversion and wired up everything like in the picture above but my wiper isn’t working still. I thought maybe the bone yard motor was bad so I ordered one and that one doesn’t work either. I checked the fuse and that’s good. I flipped the switch on and I can hear the Durango relay that’s attached to the wiper working. Anyone know what I’m doing wrong?