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If you’ve been around here a while, you probably remember my last post on the skid plate to protect our ProMaster’s second alternator.  But just in case you haven’t, let me bring you up to speed.

A number of ProMaster based RVs have a second alternator installed as part of their electrical system.  Besides our own Travato – which is a bit special – the second alternator can be found in the Roadtrek Zion and the Hymer Aktiv.  This second alternator rides pretty low to the ground, and when you see it, you’ll be a bit concerned about whacking it into a “retread snake” along the interstate.  Leaving the alternator exposed, or using a flimsy plastic cover on it weren’t options for me.  So we partnered with EDGE Motorworks, in California, to develop a way to protect this vulnerable alternator.  After two iterations, the alternator skid plate looked like this:

This was version 2.  Version 1 was a steampunk looking affair.

Before we go any further, I’d like to acknowledge that what we’re developing here might not fit everyone’s definition of a “skid plate”.  I would not – as one commenter suggested – attempt to jack up the RV by this tray, for example.  Depending on your point of view, you might see this as an “undertray”, a “guard”, or a “shield”.  And those might be more appropriate terms around the garage.  But this is an RV website, and not an off-roading one.  So while I respect the difference in terminology, I plan to continue using all of the terms more or less interchangeably.  I think we all know what I’m referring to.


Now, that last version was a solid attempt, and it stayed in place on Lance through a couple months of testing with no failures, and never so much as a rattle.  But we knew we could do better.  Right away, after installing this skid plate, we identified three areas where where could improve:

  1. Thicker Material. This skid plate was made out of 16 gauge steel.  We wanted to do better, and work in 1/8″ thick steel.
  2. Better Mounting. Rather than tapping into sheet metal, we wanted a more solid mounting point.  We wanted to bolt on to the frame rails.
  3. Angles.  We wanted to angle and curve the front of the skid plate to present a glancing surface to obstacles.

So, after two or three months of testing, it was time to head back to EDGE Motorsports for the next iteration of the skid plate. Once again, Stef didn’t come along, and she’s probably really glad, because Lance spent most of the week inoperable and ugly in the parking lot.

Stay classy, Lance.

But in the end, I’m happy to report the new fitment went well, and now I feel more like I’m driving a tank.

Mad Lance

You’ll notice there that we’ve swapped out Lance’s nose ring for more of a full face mask.  I’m not sure if I dig the black color yet, and we may be changing that at some point.  The reason we did this was simple.  We wanted to have a look at something that securely attached to the frame, so we could base our skid plate mounting off that.  This grill guard attached to the frame, so we got one to study.  As a result, the new skid plate attaches to the frame, and will work either with or without this grill guard.  When all was said and done, we had the grill guard sitting around, so why not mount it?!

This skid plate is only falling off if the whole bumper falls off.

This mounting scheme addresses the second of our areas for improvement.  Whereas the first version of the skid plate was installed with self-tapping screws into sheet metal.  This thing is bolted onto the frame with bolts that I can’t torque the heads off of.  (I have a really bad habit of torquing the heads right off of bolts.  This probably has more to do with the fact that I buy lots of cheap Chinese bolts than it does with my strength…)

Apart from the “Mad Max” grill guard, the improvements to the skid plate are substantial.  Addressing the first of our areas for improvement, this thing is over seventy pounds of thick (.125″) steel.

So beefy, it was a pain in the a** to move around!

You’ll notice that this one is considerably bigger than version 1.  We reasoned, if we’re going to protect things underneath the rig, why not go all the way.  This new skid plate protects the oil pan, the pan underneath the transmission, and pretty much anything else you can see in this picture.

The seamy underbelly of a ProMaster…

This meant, of course, that we had to cut a hole in it to allow access for changing the oil without removing the whole affair (because removing it is pretty difficult).

We could’ve cut the hole a hundred yards wide, and the guys who change my oil would still find a way to make a mess of things.

The size and weight of the skid plate meant it took two of us to install it properly.

Don’t be fooled by the alignment rack.  I’m actually holding up the entire rig here.

Once we got it up, we were able to get a good look at the clearance picture to the second alternator.  We felt like this was adequate clearance to all belts, hoses, and electrical parts.

Plenty of space in there.

You’ll notice the slick curve under the second alternator.  This, and the angled front of the rest of the skid plate addressed our third area for improvement.  But fashioning this curve was a bit difficult, and required lots of gratuitous welding and sparks to get it just right (it only took us two attempts).

I checked it out. It’s actually an OSHA regulation that all welding gloves, jackets, and helmets have to have flames on them.

So now, with everything mounted, up, it sort of looks like this:

I WANT to run over things now…

And with that, it was time to leave EDGE and head for home.  On the way back, I stopped at a Starbucks.  When I got out, I happened to snap this picture of the underside of the rig as I had rolled up to the curb.  If anyone wonders why I’m eager to have something protect the second alternator, this picture pretty much explains it.  Without a skid plate, this curb would have hit it.

This makes me uncomfortable to look at.

So – Let’s Hear It!

And now we’re throwing this open to our readers.  We feel like the design of this thing has progressed enough to where we could entertain a few early adopters.  We can actually produce these things either with or without the bubble to protect the second alternator, so our audience is a bit wider than just those with the second alternator.  Our ideal early adopter would:

  • Reside close to the Mountain View, CA location of EDGE Motorworks
  • Have a Roadtrek or Hymer ProMaster-based rig with the second alternator installed
  • Or, have any ProMaster where protection of the undercarriage is desired
  • Be patient and understanding as we work to progress this further

If this sounds like you, please sound off in the comments below.  Do include your email (the emails are not published, only I will see them), and let us know if it’s OK to contact you about this.

And now, I’m off to go rock crawling in my Travato!  (just kidding)