Double threaded bolt on winch plate! HELP!
JK Junkie
Joined: Nov 2011
Posts: 2,199
Likes: 218
From: Over the hill
I don't disagree with the data. My view is that when a grade 8 fails, it snaps. When a grade 5 fails, it bends first and dissipates energy. If you talk to people in the rigging industry, they don't use grade 8 for anything. Another example is that Factor 55s locking winch bolt is grade 5 (they know a little about winching and strength).
Talk to the guy that runs Rausch Creek. He's seen first hand when winch bolts sheer and the winch let's go. Same story each time; bolts replaced with off the shelf grade 8.
Obviously, it's just my opinion based on my research. I'm not an authority on the topic, but logic tells me that there is wisdom in crowds.
Talk to the guy that runs Rausch Creek. He's seen first hand when winch bolts sheer and the winch let's go. Same story each time; bolts replaced with off the shelf grade 8.
Obviously, it's just my opinion based on my research. I'm not an authority on the topic, but logic tells me that there is wisdom in crowds.
Last edited by Mr.T; May 27, 2014 at 07:28 PM.
JK Junkie
Joined: Nov 2011
Posts: 2,199
Likes: 218
From: Over the hill
Here's an excerpt from the manual for my winch (superwinch 9.5i), apparently they have no problem with using grade 8 instead of grade 5.
If it really was a safety issue, and with all the internet controversy for years, I don't think they would be stupid on this, or asking for negligence lawsuits.
Edit: This is from a Warn manual http://www.warn.com/truck/winches/im...87969A0_rs.pdf
WARNING: If different length bolts, nuts, washers and other hardware are required for your installation, always use hard-ware that equals or exceeds the strength grade of the supplied hard-ware.
Edit: This is from a Warn manual http://www.warn.com/truck/winches/im...87969A0_rs.pdf
Installation Safety
Always use grade 5 (grade 8.8 metric) or better hardware.
Always use grade 5 (grade 8.8 metric) or better hardware.
Last edited by Mr.T; May 27, 2014 at 07:38 PM.
JK Enthusiast
Joined: May 2010
Posts: 307
Likes: 0
From: Louisiana
You think you'd shear 4 properly torqued properly sized bolts, before you'd snap the cable or rope?
Also I've never seen a winch that could squeeze through the fairlead even if it did shear the bolts...
Also I've never seen a winch that could squeeze through the fairlead even if it did shear the bolts...
JK Junkie
Joined: Nov 2011
Posts: 2,199
Likes: 218
From: Over the hill
Bottom line is that two major winch manufacturer's plus a fastener manufacturer say it's fine to upgrade to grade 8 from grade 5. They've got liability, skin in the game.
JK Enthusiast
Joined: May 2010
Posts: 307
Likes: 0
From: Louisiana
Don't think they'd design the bolts to fail before the winch rope. There's a shear strength calc in the link at post #18 above. Bottom line is that two major winch manufacturer's plus a fastener manufacturer say it's fine to upgrade to grade 8 from grade 5. They've got liability, skin in the game.
JK Enthusiast
Joined: May 2010
Posts: 307
Likes: 0
From: Louisiana
Did those winches that "let go" pull through the fair lead like a cartoon?
JK Junkie
Joined: Jun 2013
Posts: 3,697
Likes: 2
From: Grosse Pointe, MI
Well, sounds like either are fine and my reading had been biased to grade 5 believers.