Problem with RCI Skid Plate-- Is this normal?

I received my RCI Skid Plate for my 18 Tacoma about three weeks ago. These photos were taken after about fourteen days on the truck. I live about 300 miles from saltwater and the truck has been garaged for the majority of those two weeks... The bolts I received for the filter door were more of a blued button bolt, not the stainless or "stainless color" as shown on their website and other pictures on google. So I did the reasonable thing and reached out to RCI... Their response was that they were industry standard zinc coated bolts. I understand that stainless is softer, but how can this be normal? Has anyone else had this issue? Not trying to bad mouth them as the skid is really well made, I just cant see how this is normal. In any google search, forum search, or anything I cant find the same condition. Two weeks literally!

 

Bad batch? That’s quick if it’s only been installed for 2 weeks.

Take em out go to hardware store and grab the same size in stainless, probably less than $3-4.

 

Yikes. Pull those fast

 

Sounds like you received black oxide coated bolts, (or similar) and not zinc coated bolts. Get those out now.

(Getting up on soapbox for my suggestions on best practices)

Best suggestion is to install cadmium plated bolts. These are generally golden colored and provide good corrosion with good electro compatibility with the (I assume) 5052 skid.

Next best suggestion would be zinc plated bolts. They should be shiny silver colored. These will eventually rust, but before they do they will protect your aluminum skid. But they are easy and cheap to replace every 5 years or whatever.. (compared to an aluminum skid)

Lowest recommendation is stainless bolts, not because of strength but because of corrosion potential on the skid. If you really want stainless bolts, use a zinc or cad washer under them. Hopefully the washer will corrode first and you can replace it after a few years or whatever.


When it comes to different metals attached together, the most reasonable course of action is to try and match electro potentials. Where the mismatch occurs, a bolt is cheap to replace, but it needs to be inspected and replaced when the coatings start to break down before it completely goes to pot.

The more negative item corrodes first.
Zinc is extremely negative voltage, aluminum and cadmium both negative but less so, most stainless are barely negative. Titanium and graphite very positive.

[Edit to clarify. Stainless bolt wont corrode much, but it will try to corrode your expensive aluminum skid plate]

 

Its on the bottom of your truck, and Im guessing you live in the saltbelt judging by your comment.. Either pull them out and getting identical hardware, in stainless, from your local supplier. Or just hose it down with a little Fluid Film. (At that point, just do your whole truck yearly to avoid all other underside rust)

 

Using stainless bolts in aluminium with introduce corrosion through galvanic corrosion, the aluminum threads over time with moisture will be eaten away. In practice, they typically recommend using a sealing washer when doing this. However the holes are likely open on the other end so that wont do anything here.

That's not even the worst scenario as galling (stripped threads) becomes more of an issue (stainless/aluminium), assuming those bolts thread into the aluminum plate. At least RCI weighed the application/serviceability over appearance.

I'd just wire brush them and spray them the head with zinc rich primer (silver).

 

This. Prinsu rack owners that swapped their bolts out for SS can experience the same issues.

 

My rci skid bolts did the exact same thing.... just switch them out like others have stated

 

Ouch
I didnt even think about the fact that those are threaded into the aluminum... (looks from pictures like it is a tinnerman type nut on the inside)

 

Can anyone post a link where I can get some online? I’m pretty upset RCI just blew it off.

 

Wow, that looks like crap, replace those ASAP. Good luck.

 

What size bolts are these? I just installed mine this past weekend. Guess I might as well replace them

 

Milk of magnesia FTW

 

I just found a few pics and you're right, they look to be u type extruded tinnerman nuts. Stainless would be fine, better in this case as I have had several extruded tinnerman nuts with zinc plated fasteners seize together over time.

 

According to Jeff at RCI, those are M8x1.25x25mm. If you find a link online just let me know. What kind of washer would you get?

 

Thanks, will do. I’ll probably run down to the hardware store to get replacements

Is this the only known issue with the hardware, or do the carriage bolts and everything else rust too?

 

The front two bolts you reuse from the stock hardware. The rear bolts I received are zinc coated, and so far show no signs of rust.

 

You want to make sure you use "304" stainless screws in aluminum. Generally, stainless is the recommended/industry standard for aluminum parts...but not all stainless steel is the same. Link below may be helpful.

$8 M8 Button Head Torx Socket Cap Machine Screw,304 Stainless Steel,Pack of 8-Piece (M8 x 25mm)

https://www.amazon.com/Button-Socke...4&qid=1551817045&s=industrial&sr=1-5-fkmrnull

You can also countersink the screws. You will need a countersink bit and these screws.

https://www.amazon.com/1-25mm-pitch...inless+304&qid=1551817417&s=industrial&sr=1-6

 

https://www.mcmaster.com/

Great place to get hardware.

 

Dang got the same issue with the bolts 6 weeks on the truck. I really like the skids but you'd think RCI would change the bolts they're using, now I have to go out and get new hardware. No Big deal...…….