Calgary Jeep Association
4x4 Related Groups => Tech Talk => Topic started by: M T on April 30, 2010, 10:02:10 AM
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I was wondering if the 4 bolts that secure the 2 factory two hooks on my TJ are strong enough to secure the winch plate? And does anyone have any ideas to make the winch and winch plate more 'anti-theft'? I was planning on using the factory torx bolts through the tow hooks and winch plate.
Thanks.
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That's exactly the setup I have with my winch: tow hooks, torx bolts and all, I have had no problems with multiple pulls. I figure since each stock hook is rated at 8000lbs it should be fine. The only Idea I have heard to make it more anti theft is tac welding the bolts
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Make sure the bolts are grade 8 for the tow hooks and there will be no issues bolting the winch plate with the tow hooks. Also as mentioned just tack weld the winch bolts to the plate
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I would assume the factory torx for the tow hooks are a grade 8 or equivalent?
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I would assume the factory torx for the tow hooks are a grade 8 or equivalent?
I think they are only grade 5.
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new winch plates usually come with new bolts. Hit Bolt Supply and pick up some new grade 8s.
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If you're adding a winch plate, you'll probably need longer bolts anyways. Upgrading to Grade 8 at the same time is a good move in the long run - cheap hardware on recovery points can lead to some very, very bad things.
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you'll probably need longer bolts anyways.
Very true - the bolts were longer!
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Never really questioned the stock recovery bolts before. I just assumed that they would be the correct grade for towing/pulling out a Jeep. Eitherway grade 8 seems like the proper way and recovery hardware is not something I want to be meeting minimum requirements on. Btw the stock bolts thread all the way through ( aka long enough)...just thought i'd mention that don't want anyone thinking I'm insane...
http://www.rockcrawler.com/techreports/fasteners/index.asp
"Another good point to make is to never reuse fasteners after they have been subjected to loading or the elements. Corrosion can cause a fastener to fail well below its initial strength. So be smart and use only new fasteners when installing or reinstalling some cool new widget on your rig."
My stock tow bolts certainly have been subject to some fairly hard pulls before i put them on the winch plate. Good day on the Jeep forum......learned my recovery hardware I've been using is mediocre and probably inadequate :(
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There is probably nothing wrong with your factory bolts. The factory wouldn't use them if they weren't adequate. In fact there are many instances in hitch and recovery equipment where a "sufficient sized" grade 5 bolt is better than a gr8. Gr8 bolts are hard and brittle and can snap if subject to impact blows whereas a gr5 bolt will survive because it will stretch.
Tow hitches often come with gr5 for this reason. Mac trucks had a recall where there flywheel bolts were shearing off. The fix was to replace the factory installed Gr8 bolts with Gr5 bolts as the gr8 were found to be too brittle for that application.
I've found that usually the factory installs pretty good quality bolts, take trac bar and control arm bolts for example. They are metric 10.9, much better than off the shelf 8.8.
Generally it is safe to say that GR8 is better than Gr5 but be aware that its not so cut and dry and there are other factors to take into consideration.
That being said if I replace a factory bolt I make sure to use equivalent or better and for recovery stuff if I'm buying new bolts anyway I try to get GR8. Unless for factory bolts are rusted or otherwise damaged I would reuse them. Also once that winch plate is on it ties both sides together and the whole thing will be stronger.
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There is probably nothing wrong with your factory bolts. The factory wouldn't use them if they weren't adequate. In fact there are many instances in hitch and recovery equipment where a "sufficient sized" grade 5 bolt is better than a gr8. Gr8 bolts are hard and brittle and can snap if subject to impact blows whereas a gr5 bolt will survive because it will stretch.
Tow hitches often come with gr5 for this reason. Mac trucks had a recall where there flywheel bolts were shearing off. The fix was to replace the factory installed Gr8 bolts with Gr5 bolts as the gr8 were found to be too brittle for that application.
I've found that usually the factory installs pretty good quality bolts, take trac bar and control arm bolts for example. They are metric 10.9, much better than off the shelf 8.8.
Generally it is safe to say that GR8 is better than Gr5 but be aware that its not so cut and dry and there are other factors to take into consideration.
That being said if I replace a factory bolt I make sure to use equivalent or better and for recovery stuff if I'm buying new bolts anyway I try to get GR8. Unless for factory bolts are rusted or otherwise damaged I would reuse them. Also once that winch plate is on it ties both sides together and the whole thing will be stronger.
Sorry, but no.
The "Grade 8 is too brittle" is a myth. The difference in strength between Grade 8 and Grade 5 is enough that before a Grade 8 even begins to deform, a Grade 5 has already suffered catastrophic failure.
Here's the link with the specific data to back this up.
http://www.rockcrawler.com/techreports/fasteners/index.asp (http://www.rockcrawler.com/techreports/fasteners/index.asp)
The reason that most hitches/winches/etc. come with Grade 5 bolts is that they are cheaper and most of the time they are "good enough".
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My winch plate used the factory bolts. Been on for f0ur years, lots of use, no issues. The only thing I had to do is swap the front tow hooks left to right for clearance up against the winch plate.
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Hmm, I stand corrected. Thanks, thats a good read. Ratioally a gr5 is less brittle than a gr8 but its a pointless argument as the article pointed out by the time a GR8 bolt begins to deform a gr5 has already failed.
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I can't take credit for the info...I got it from another thread on the board. I think BlackYJ posted the link initially.
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It's been tossed around for a while, but it IS a good article to keep bookmarked. Seems to be needed at least twice a year. I think I even stickied it on RDJP.