3/31/19 Folding Mirror Update:
I've had more requests than I expected for the 3d printed parts. I decided to upload the .stl files to thingiverse and make them available for others to print. I'm also willing to print these parts and ship them to you for $150. Please read the writeup below carefully though and understand that you will need access to a mill (manual bridgeport type is fine) and drill some holes in your door panel.The holes are entirely covered by the mirror and not visible whatsoever. The parts will also require some amount of finish work (bondo, sanding and paint).
The .stl files can be found here. Each housing is 4 pieces that need to be glued together. I did this so that it can be printed on most desktop FDM printers and to minimize support material requirements. I've also included the milling fixtures that hold the die cast parts at the correct angle so you can face them down. There is also a drill jig that can be used to locate the new holes off of the existing holes. https://www.thingiverse.com/thing:3529719
Creating these models did take a significant amount of effort and time. I do request that if you download these files you consider sending me a tip so I can continue to fund these types of projects.
I think $50 is reasonable but will leave that to your discretion.
I am accepting donations here: https://www.paypal.me/sormaz
Also please be aware that I am making this data available only for personal use. Please do not try to resell my work. Original post:
Well I've finally done it. After having some chinesium "new style" manual fold tow mirrors on my truck for over a year, I got fed up with the bad chrome fading and not having the coolest feature the fancy new trucks have, the power fold.
I now have what has been referred to as "the holy grail"
. Fully functional OEM power folding tow mirrors, with power +memory tilt (reverse function works also), heat, turn, clearance lights, puddle lamp etc.
Thought this was cool enough to share. There is a possibility I'd over this as a service for folks, but it is quite a bit of work so I'm not sure I'd want to take that on, and cost would be pretty high. Maybe willing to offer a DIY kit of sorts - will gauge interest in the near future. Here are the steps required to retrofit OEM powerfolding tow mirrors onto a GMT 900 truck:
- Create new plastic truck-side housings
- Modify mirror mount bracket
- Drill new hole pattern in doorpanel
- Invert up/down mirror tilt motor direction
- Repin connectors
- Install and Flash DL3 powerfold window switch modules (these exist for the "small" power folding mirrors that were available for our trucks)
is probably the most prohibitive. All aftermarket retrofit options utilize a GMT900 style mounting bracket (the part that physically bolts to the truck) which is a lot smaller than the bracket that houses the fold mirror. This means that there is no readily available plastic cover that fits the motor housing, and also matches the door profile of our trucks. Luckily I was able to acquire cad models for both style housings, got them drunk and made a baby.
I printed the housing on my buddies 3d printer, smoothed with bondo and abrasives, then applied a texture coating and paint to match the look of the injection molded part. (this is the time consuming bit)
I was pretty satisfied with the result. This picture shows the OEM 2015+ housing (right) the OEM 2012 housing off my truck (middle) and their love child (left). Step 2
is to hack up the beautiful die cast motor housing to make it fit your truck. This is not really a reversible process, and the only way I know to get these is to buy an expensive mirror assembly, so you are committed at this point. First order of business is to use the bandsaw to lop off the front corner of the housing, or if you are like me and just too excited about how well your freshly replaced blade is cutting at 2am, you pay no attention as you cut off the top corner, throw a couple things, go home, come back and JB weld the sucker together.
Again I made use of the 3d printer to make a milling fixture that holds the housing at the correct angle. Machine down a significant amount of the ribs, locate and re-drill and tap the remaining 3 stud mounts for a 12-24 thread. Step 3
is fairly straightforward, I didn't take any pics (will next time I take the mirror off), but created a template to locate the new holes off the existing holes and drilled them through. One of them is pretty close to an existing hole so it becomes a snowman, but not overly concerned about it as it is the lowest hole and primarily loaded in compression. Step 4
was a nice surprise, I installed the mirror to find that the up/down tilt actuation was reversed. This wouldn't be too big of a deal, but with the memory function enabled on the mirrors, this causes it to drive all the way to the down position every time i unlock the truck, which is not super useful. So again the mirror gets disassembled, motor removed, cut out the integrated wires for the up/down motor and soldered on new jumper wires to cross them over. Luckily these motors are available individually (p/n 22919754) for about $50 if you screw it up. Step 5
was actually pretty straightforward. I left my diagram at the shop but will upload it when I remember. Thankfully the new mirrors use the same connector family so the pins are actually the same. Most pins map over to connector J3, but I also had to buy p/n 15127040 which is J7 on the diagram. J7 gets the power fold pins, as well as the tilt position sensor pins. All of this info is available in the electrical manuals available online. The harness ends up a little short to reach the window switch, but with some massaging you can get it there. Step 6
, finally you are going to need to install p/n 20835553 which is the window switch assembly with power fold buttons for option DL3. I couldn't find a reasonably priced bezel with the brushed aluminum finish, so I just spent some time with a dremel adding the additional button cutouts, which actually turned out really well. On the left is my stock window switch, and the right is the DL3 window switch with the power fold buttons. I don't have a before picture of the bezel, but you can imagine I only had to trim back the top of the black part that interfered with the new buttons.
And that's it, job done. Click 2nd pic for video:
I'm about 50% through with the passenger side mirror, will update if there are any surprises on that side. Haven't gotten to step 4 yet, kind of interested to see if it has the same issue. I suspect either both l/r and u/d will be inverted or both will be correct, as it appears to be the same motor mounted at a 90deg angle.
I'm also working on something else pretty cool - will post a separate thread soon. I have a prototype power extending actuator built that should be compatible with both OEM and aftermarket versions of this style mirror and add some pretty sweet functionality if you are like me and forget to pull your mirrors out every time you hook up a trailer and have to pull over at the gas station before the on-ramp to do so. teaser here: https://www.instagram.com/p/BpTld85nxEB/