What's new
By:
Ram Heavy Duty Forum

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

WTF, no really WTF

DCC

DCC

Member
Messages
38
Reaction score
94
Points
18
Location
Tampa, FL
I was installing running boards on my 3500 and the manufacturer (who will remain nameless at this point because I'm still working on a fix) decided to replace the hardened bolts that attach to frame with (what appears to be) a weaker Chinese replacement. The "WTF" bolt stripped when I put it on. This is the top of the bolt.

WTFBOLT.jpg
 
Stripped as in the threads on the bolt stripped or the threaded sert it goes in? Grade 8 bolts are typically quite strong for corresponding size. Follow the torque recommendations with a torque wrench? Or is that the sert installation tool?
 
I would like to believe that the 8.8 rating on that bolt is accurate. Def not stainless. The problem was the instructions gave torque ratings at 58 fl lbs for a 12mm bolt size. That bolt in the picture is 13 mm. So I went conservative and torqued to 58 ft lbs with a brand new Dewalt torque wrench. Literally, it was the first bolt I torqued with this wrench. Well, after looking up the torque range on a 8.8 bolt, 58 ft lbs is about double what its rated for. So, no wonder it stripped. My gripe is that 1) the manufacturer is not using a hardened steel bolt and 2) they did not update the torque table in the instructions.
 
When you look up a bolt torque table the measurements are of the bolt diameter itself not the head measurement. That looks to be about an 8mm-10mm which would have an optimal torque of about 20-40 lb/ft depending on the actual diameter.

Lets see a picture of the directions sheet
 
Really looks like the riv-nut install tool that Mopar sells to install their running boards.
 
Here's the instructions sheet. So, just to reiterate, that bolt is 13mm, not 12mm not 14mm.
Instructions.jpg
 
DCC said:
I was installing running boards on my 3500 and the manufacturer (who will remain nameless at this point because I'm still working on a fix) decided to replace the hardened bolts that attach to frame with (what appears to be) a weaker Chinese replacement. The "WTF" bolt stripped when I put it on. This is the top of the bolt.

View attachment 31610
Click to expand...
Your running boards attach to the frame?
 
  • Like
Reactions: DCC
What I'm holding in my hand (in the previous picture) is the 3# M8 Bolt Plate. The reason I'm calling this out is that the instructions picture is different than what that plate is. The instructions seem to indicate there is a nut tack welded to the plate. But what I actually have is a flat head bolt tack welded.

Also, just from a structural standpoint, since this bracket is attached directly to frame, I would expect something I bit stronger.

platedrawing.jpg

20220209_012328515_iOS.jpg

of course the one time I need my caliper, I can't find it :)
 

Attachments

  • platedrawing.jpg
    platedrawing.jpg
    92 KB · Views: 18
  • boltplate.jpg
    boltplate.jpg
    471 KB · Views: 18
It also appears that that bolt is meant to be threaded in from the opposite side you have it all the way through, then put through a hole somewhere with a nut on the other side of the directions picture is correct. Likely through a hole in the mounting area on the truck. The picture clearly shows the bolt installed and going through the bracket on the same side as the welded nut on the other side.
 
They should remove the 12mm and 14mm torque specs, since there isn't that size fastener listed on the contents.
Also don't overthink it. If it's a small bolt tighten it up good with a standard length 3/8" drive ratchet.
 
Im not seeing any issue other than you way over torqued the bolt thinking the head size was the bolt size…. Also 8.8 is considered hardened for metric zinc coated fasteners you wont see 10.9 or 12.9 unless its a structural bolt usually so this is not on the manufacture in anyway so just go buy a new bolt and continue installing the steps

#3 clear depicts it how it is the nut is tacked on and the bolt is tacked on as designed
 
  • Like
Reactions: DCC
Thanks for the info guys. So, yeah, I misread that instruction sheet. For those of you wondering, here's the picture of the install from the instructions....

rbplateinstall.jpgrbbracket.jpg
 
You must log in or register to reply here.
Back
Top