Jeep Wrangler JK and JL Factory Bolt Sizes
0Every Jeep owner who uses their vehicle as intended and goes wheeling, whether it’s simply trail running, overlanding or hardcore rock crawling, should consider having few spare bolts as part of their recovery kit. Your tool bag, recovery gear and spare parts could be the difference between getting stranded in the middle of nowhere, and returning home safely after having a great time on the trail.
Even if you personally don’t loose a bolt while offroading, somebody in your group or a stranger you meet, might at the most unexpected moment discover that one of their bolts or nuts is missing and it’s preventing them from continuing to drive.
You might be a DIY’er who likes to work on their Jeep and install some new upgrades yourself, but accidentally break or loose one of the bolts. You might be buying a used Jeep from somebody else and want to replace some parts and need new bolts while doing so.
That is why I believe that a few spare bolts should always be kept in your Jeep.
The Jeep community appears to be divided when it comes to the issue of using stock, grade 10.9 metric bolts versus replacing them with grade 8 bolts. Several bolt kits available from some vendors, promote them as an “upgrade” to factory bolts, claiming that the grade 8 bolts are stronger, they are the proper size, they’re shouldered, and will prevent issues like the dreaded “Jeep wobble”.
After researching the issue extensively for a long time, and experiencing the death wobble once myself, I am personally of the opinion that the factory bolts are the proper hardware for the Jeep. Even after installing a 3.5″ lift on my 2012 JK, I am still using the stock bolts. One thing that is crucial is making sure that all bolts are torqued to specification.
There is no need to spend money on new bolts. Those funds can be better spent on a different upgrade. If you really want to spend money on your Jeep, invest in a good torque wrench and use it as a part of regular maintenance.
My intention is not to claim that I am correct and the factory bolts are the only correct solution. If you are convinced that grade 8 hardware is something you need, you are free to purchase and install them.
Here are just a few arguments behind my decision to continue to use the stock bolts.
A 10.9 metric bolt is equivalent in strength to a grade 8 SAE bolt. They have approximately the same tensile strength.
The factory bolts are considered softer that the replacement bolts sold in the kits. A softer bolt isn’t always a bad thing. They will allow for some stretch. A hard bolt will not and is far more brittle and prone to breaking.
Replacing your stock hardware with different grade bolts means that factory torque specifications no longer apply and there are no official specs for the “upgraded” bolts used with your Jeep’s suspension and steering components.
These may in fact require a lot more torque to hold tension and not loosen. This could damage the crush sleeve, bushing, heim joint, or whatever else was not designed to be crushed as hard.
As for the argument against the factory fully threaded bolts, here is an opinion I read of an experienced jeeper: “When you look at the bushing of your track bar or control arms, the metal piece in the middle where your bolt will go through is called a ‘crush sleeve’. It’s designed to get pushed really hard from either end. The purpose of your bolts and nuts is to provide ‘compression’ and cause your mounts to act like a vice by clamping down really hard on the crush sleeve. The crush sleeves is not supposed to rotate at all when installed correctly but rather, the bonded rubber bushing will twist around it. Of course, if you have a polyurethane bushing, heim or other aftermarket joint, the bushing will rotate around the sleeve or misalignment spacers – again, there is no movement around the bolt and therefore, shouldered bolts are not necessary. This is the reason why bolts are rated for ‘torque’ and not ‘sheer’ – the value of compression strength is all that is necessary to hold things together.”
This post is a handy list of the most common stock Mopar bolts and nuts for both the Jeep Wrangler JK and the JL. I compiled the below Jeep Wrangler factory bolt sizes information based on my own research and purchases from a Chrysler dealership and online parts vendors.
Disclosure: This list is not an official guide and should not be used as the ultimate and only source when purchasing bolts and nuts for your own Jeep. Based on your model year and trim, there might be discrepancies between what is listed below and what is installed on your Jeep Wrangler. Please consult at least one other source before making any purchases. I take no responsibility for any damage or injury related to any hardware you install on your vehicle.
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