Disclaimer: This information is specific to my axel models and may be different from year to year against same axel models. Mine is a 2024 Rubicon with M210 and M220 axels. I’m posting this to help clear up some of the misinformation I have come across for others who plan to do this task.

When changing the Diff oil I realized they cheeped out and didn’t provide drain plugs in my build. The exercise turned into a typical series of automotive repair frustrations, much of which came from reading a lot of misinformation post on forums from people who have either themselves been misinformed, or have some self generated belief of the appropriate approach. Because of this I wanted to post what I learned, and post the remaining questions I still have in hope to help others and close any gaps in understanding.

Also contradictory is the specifications posted by Dana, and how it differs from the Jeep Tech Connect dealer repair manual instructions. Their torques are very different. I’m sure each is correct within certain parameters, and I’m also certain that you can utilize various procedures in sealing your covers and have success. I have a lifetime of mechanical experience, with ASE and other certifications including being an aircraft mechanic. Sometimes I adhere to procedure and other times I lead with experience. In this case I’m inclined to follow the procedure outlined by Jeep (You do you).

The upsetting part of this is that it’s all unnecessary for such a simple procedure to be so over engineered and as complicated, and I only accidentally found out thatch bolts are intended for one time use when seeking out torque specs. When I asked the dealer even their techs were in conflict of the correct procedure, and it wasn’t until I obtained the procedure that it was clarified.

The brilliant engineers decided to employ whats believed to be a reusable gasket, but also used NON_REUSABLE bolts, and no drain plug. Top notch planning. I said believed to be because its certainly the type of gasket that can be reused, but I’m not 100% sure if the embedded spacers at screw locations have any crush feature, or are simply spacers to hold a fixed distance. In the moment since I had already drained my oil I did reuse the gasket and bolts, and torqued them to 20 ft lbs., and it held without leaks thus-far, but I have ordered new gaskets and bolts. When I have the cover off I will compare the spacer dimensions against a new gasket to cull that out.

In my opinion the bolts are not to be reused for two primary reasons: 1) They come with a chemical locking feature (like Locktite) that is doing two things; a) its preventing loosening of the screws over time. b) It may be adding run-on torque. (When I obtain my replacement bolts I will be able to confirm this.) The run-on torque changes the procedure when tightening. Therefor when people attempt to use the varying posted torque specs they are sometimes exceeding the bolt yield, sometimes breaking from over-torquing. 2) the intent is the bolts are to be tightened to attain a stretch which is increasing the chance of breaking the fastener on a second torquing attempt.

As noted there are multiple ways this can be approached including aftermarket covers, and various gasket types. I seriously considered the ARB covers because of the drain plug, but I didn’t want a $400 bill to do that and don’t need them. Also too, I’m doubtful that they will drain out to the bottom where the most contaminated oil resides.

The only part of the Jeep Service procedure I’m uncertain about is why they have different torque procedures between the front and rear axels. There could be a valid reason for this or simply that two separate engineers developed their own proceeder, but if any one factually knows please chime in. I tried to call Dana, but good luck.


Excerpts from M220 (rear) Axel Jeep Procedure below, Sequence attached:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover Bolts 41 N m (30 Ft. Lbs.)

Excerpts from M210 (Front) Axel Procedure:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover BoltsTorque procedure:

l Tighten to 20 Nm(15 Ft.Lbs.)

2 Rotate Additional 20°

I hope this helps

Who in their right mind would make an axle without a drain plug. Especially on a 4x4

 

Apparently Dana and AAM also as my power wagon was the same way.

 

Good info. I wonder the bolt part numbers?

 

Maybe I am simply ignorant here, but I have never heard of a NON-reusable bolt!
WTF?
How hard would it have been for them to use a NORMAL, reusable bolt here? Again, I am left scratching my head.

Excerpts from M220 (rear) Axel Jeep Procedure below, Sequence attached:​

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.​
• Differential Cover Bolts 41 N m (30 Ft. Lbs.)​

"IF removed"? Don't they mean WHEN removed?

Are they honestly expecting that Jeep owners are NEVER going to change their diff fluid?

I am simply dumbstruck by the level of sheer stupidity with the designing here.

 

one use bolts are common. lots of applications in automotive and in motorcycles have one use bolts. nothing new.

 

I generally buy new grade 12.9 allen head M8 x 1.25 thread bolts with small OD AN washers, length chosen to give good thread engagement with the cover and gasket chosen. If I am installing a strong cover, I generally use RTV sealer on the mounting surface and threads so the cover can potentially strengthen the assembly. I tighten in a cross-pattern but didn't even know the factory had the above recommendations.

 

Most likely, the reason Jeep tells us to buy new cover plate bolts is because of the locking agent on the threads of the bolts. I seriously doubt they are using "torque to yield" bolts on a stamped steel cover plate. People are pulling and replacing the covers all the time changing the fluid and I have not heard of any bolts breaking off and covers leaking. Besides, the bolts are not being subjected to large stretching forces such as a fastener in a clutch pressure plate or cylinder head bolt. Those are supposed to be changed each use and most are not. People can buy new bolts if it makes them feel better, but I doubt it's necessary. A drop of blue loctite on each bolt should accomplish the same.

Ironically, I am trying to figure out a way, for a while now, of buying a front and rear ARB black nodular iron covers. Like OP, I cannot justify $400 for covers.

As to the gasket being reused, if it isn't leaking then it's fine to reuse.

 

Disclaimer: This information is specific to my axel models and may be different from year to year against same axel models. Mine is a 2024 Rubicon with M210 and M220 axels. I’m posting this to help clear up some of the misinformation I have come across for others who plan to do this task.

When changing the Diff oil I realized they cheeped out and didn’t provide drain plugs in my build. The exercise turned into a typical series of automotive repair frustrations, much of which came from reading a lot of misinformation post on forums from people who have either themselves been misinformed, or have some self generated belief of the appropriate approach. Because of this I wanted to post what I learned, and post the remaining questions I still have in hope to help others and close any gaps in understanding.

Also contradictory is the specifications posted by Dana, and how it differs from the Jeep Tech Connect dealer repair manual instructions. Their torques are very different. I’m sure each is correct within certain parameters, and I’m also certain that you can utilize various procedures in sealing your covers and have success. I have a lifetime of mechanical experience, with ASE and other certifications including being an aircraft mechanic. Sometimes I adhere to procedure and other times I lead with experience. In this case I’m inclined to follow the procedure outlined by Jeep (You do you).

The upsetting part of this is that it’s all unnecessary for such a simple procedure to be so over engineered and as complicated, and I only accidentally found out thatch bolts are intended for one time use when seeking out torque specs. When I asked the dealer even their techs were in conflict of the correct procedure, and it wasn’t until I obtained the procedure that it was clarified.

The brilliant engineers decided to employ whats believed to be a reusable gasket, but also used NON_REUSABLE bolts, and no drain plug. Top notch planning. I said believed to be because its certainly the type of gasket that can be reused, but I’m not 100% sure if the embedded spacers at screw locations have any crush feature, or are simply spacers to hold a fixed distance. In the moment since I had already drained my oil I did reuse the gasket and bolts, and torqued them to 20 ft lbs., and it held without leaks thus-far, but I have ordered new gaskets and bolts. When I have the cover off I will compare the spacer dimensions against a new gasket to cull that out.

In my opinion the bolts are not to be reused for two primary reasons: 1) They come with a chemical locking feature (like Locktite) that is doing two things; a) its preventing loosening of the screws over time. b) It may be adding run-on torque. (When I obtain my replacement bolts I will be able to confirm this.) The run-on torque changes the procedure when tightening. Therefor when people attempt to use the varying posted torque specs they are sometimes exceeding the bolt yield, sometimes breaking from over-torquing. 2) the intent is the bolts are to be tightened to attain a stretch which is increasing the chance of breaking the fastener on a second torquing attempt.

As noted there are multiple ways this can be approached including aftermarket covers, and various gasket types. I seriously considered the ARB covers because of the drain plug, but I didn’t want a $400 bill to do that and don’t need them. Also too, I’m doubtful that they will drain out to the bottom where the most contaminated oil resides.

The only part of the Jeep Service procedure I’m uncertain about is why they have different torque procedures between the front and rear axels. There could be a valid reason for this or simply that two separate engineers developed their own proceeder, but if any one factually knows please chime in. I tried to call Dana, but good luck.


Excerpts from M220 (rear) Axel Jeep Procedure below, Sequence attached:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover Bolts 41 N m (30 Ft. Lbs.)

Excerpts from M210 (Front) Axel Procedure:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover BoltsTorque procedure:

l Tighten to 20 Nm(15 Ft.Lbs.)

2 Rotate Additional 20°

I hope this helps

I received my bolts today and I think you'll either laugh, be more confused, or find some oppositional commentary. Within the Mopar package are instructions from Dana that provide blot tightening instructions which conflict with the Mopar service manual, and the published document from Dana.

In my opinion, it's getting to the point of splitting hairs, but I believe the attached instruction from Dana is probably plenty adequate, and far less complicated than the information I posted from Jeeps TechConnect.

Also keep in mind, that as a consumer you wont get access the TechConnect, and will get this instruction when buying bolts. Regardless I would plan to replace the bolts if you remove them.

 

Disclaimer: This information is specific to my axel models and may be different from year to year against same axel models. Mine is a 2024 Rubicon with M210 and M220 axels. I’m posting this to help clear up some of the misinformation I have come across for others who plan to do this task.

When changing the Diff oil I realized they cheeped out and didn’t provide drain plugs in my build. The exercise turned into a typical series of automotive repair frustrations, much of which came from reading a lot of misinformation post on forums from people who have either themselves been misinformed, or have some self generated belief of the appropriate approach. Because of this I wanted to post what I learned, and post the remaining questions I still have in hope to help others and close any gaps in understanding.

Also contradictory is the specifications posted by Dana, and how it differs from the Jeep Tech Connect dealer repair manual instructions. Their torques are very different. I’m sure each is correct within certain parameters, and I’m also certain that you can utilize various procedures in sealing your covers and have success. I have a lifetime of mechanical experience, with ASE and other certifications including being an aircraft mechanic. Sometimes I adhere to procedure and other times I lead with experience. In this case I’m inclined to follow the procedure outlined by Jeep (You do you).

The upsetting part of this is that it’s all unnecessary for such a simple procedure to be so over engineered and as complicated, and I only accidentally found out thatch bolts are intended for one time use when seeking out torque specs. When I asked the dealer even their techs were in conflict of the correct procedure, and it wasn’t until I obtained the procedure that it was clarified.

The brilliant engineers decided to employ whats believed to be a reusable gasket, but also used NON_REUSABLE bolts, and no drain plug. Top notch planning. I said believed to be because its certainly the type of gasket that can be reused, but I’m not 100% sure if the embedded spacers at screw locations have any crush feature, or are simply spacers to hold a fixed distance. In the moment since I had already drained my oil I did reuse the gasket and bolts, and torqued them to 20 ft lbs., and it held without leaks thus-far, but I have ordered new gaskets and bolts. When I have the cover off I will compare the spacer dimensions against a new gasket to cull that out.

In my opinion the bolts are not to be reused for two primary reasons: 1) They come with a chemical locking feature (like Locktite) that is doing two things; a) its preventing loosening of the screws over time. b) It may be adding run-on torque. (When I obtain my replacement bolts I will be able to confirm this.) The run-on torque changes the procedure when tightening. Therefor when people attempt to use the varying posted torque specs they are sometimes exceeding the bolt yield, sometimes breaking from over-torquing. 2) the intent is the bolts are to be tightened to attain a stretch which is increasing the chance of breaking the fastener on a second torquing attempt.

As noted there are multiple ways this can be approached including aftermarket covers, and various gasket types. I seriously considered the ARB covers because of the drain plug, but I didn’t want a $400 bill to do that and don’t need them. Also too, I’m doubtful that they will drain out to the bottom where the most contaminated oil resides.

The only part of the Jeep Service procedure I’m uncertain about is why they have different torque procedures between the front and rear axels. There could be a valid reason for this or simply that two separate engineers developed their own proceeder, but if any one factually knows please chime in. I tried to call Dana, but good luck.


Excerpts from M220 (rear) Axel Jeep Procedure below, Sequence attached:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover Bolts 41 N m (30 Ft. Lbs.)

Excerpts from M210 (Front) Axel Procedure:

• Do not reuse these fasteners. lf removed, a NEW fastener must be installed and tightened to specifications.
• Differential Cover BoltsTorque procedure:

l Tighten to 20 Nm(15 Ft.Lbs.)

2 Rotate Additional 20°

I hope this helps

First, I'll acknowledge the language in the Tech Authority Service Manual. The installation section for both the M210 and M220 state to use NEW bolts. There is also a statement in the M220 torque table to use new bolts. However, there is no statement to replace the bolts in the M210 torque table.

 

Given the above, you might think it's imperative to replace those bolts on the cover and toss the old bolts. I think there is actually a mistake in the recommendation to replace the bolts. Possibly in the torque value specified at 30 lbs/ft as well.

But, if you feel it's a requirement that if not met will result in some kind of failure, you should probably shop for your replacement bolts at somewhere other than your local Jeep dealer, since they MSRP at $50 for a set and Jeep dealers mark UP 10-20%. I've found M8 grade 10.9 (that is the strength spec) bolts for as low as 35 cents each if at least 50 bolts are purchased. If you're replacing them each time, you'll want this many bolts anyway, right?

Me, on the otherhand, I don't believe this one use requirement in the manual is correct and and violated it probably 6 or 8 times on my 2018 Rubicon. My shop that changed the gears also violated this requirement when he changed the gears. I could clearly see the factory black paint coming off of the cover bolts when I got it back. 😲OMG!

A little background on me and on "one-time use bolts". I'm a retired engineer from 30 years in the commercial airplane biz. I was a master of nothing and had a vast amount of superficial knowledge of almost everything from the nose to the tail. I was expected to be able to communicate on all kinds of issues with regulatory agencies and accident/incident investigative agencies. My formal education was in manufacturing engineering. I also spent about 15 years in the machining business.

Some "one-time use bolts" are changed after a certain use or when an engine is rebuilt, like with connecting rod bolts, because the repetitive loads may have fatigued the bolts. In certain applications, the bolt may have a requirement to be changed on how long it was used, like on a helicopter rotor. I don't think this applies to our axle cover bolts.

Many "One-time use bolts" are bolts that have a torque spec in their application where they are not just "stretched" (all bolts are torqued to "stretch"), but a "one-time use" bolt is stretched to past the point in which they will return to the same length. That is also known as past the elastic limit, or past the yield point, or sometimes called a "yield bolt". If it won't return to the original length, it may even affect the fit of the thread pitch. The reason the engineer decides to implement a "one-time use bolt" can be because they either have a limitation on the size or number of bolts that can be fit into the design to get the required clamping force. Otherwise you'd just use a larger bolt with more clamping force, right? I'm going to say, I don't think this applies to our axles either. Here's why. If the bolt torque/clamping force was critical to these axles, say to reinforce the housing with cover acting like a girdle, they would not be able to gain that reinforcement with a rubber gasket between the cover and housing. So, I neither torque the cover bolts to 30 lbs/ft nor do replace the bolts each time I pull the cover. Neither did my mechanic with 50 years specifically in the axle business.

 

 

Clearly, an improperly ground drill bit. Only one flute is cutting.

 

So, this is an informative thread - many very interesting and knowledgeable posts. I just replaced my Poison Spyder rear diff cover with an ARB cover as I had two missing bolts which I believe did not just fall out. I thought I would get two bolts from PS, but alas I saw that they are no longer in business. So, yes, I burned $200 as it was the quickest way to get a fully functioning cover in place as I did not know what spec bolt was required to do the job (as some posters have mentioned).

A couple of observations for the 45k mile interval (very unlike me to go that long) with the great majority being highway miles (no towing). I drained from the factory axle drain plug which has a magnet. I was surprised by the amount of sludge there was on it (unlike my 2012 JKR). I had used a Lube Locker gasket and reused it, which was in great shape when I pulled the PS cover off of the diff. Looking at the inside of the PS cover, there was a very, very small film of sludge on it, and the PS magnetic fill plug had a sludge buildup much like the axle drain plug. My point? Is that not having an axle drain plug is not really a big concern I would worry about IF one buys an aftermarket cover with a magnetic drain plug as it will collect the vast majority of the "free" sludge in the axle housing. Draining and refilling axle fluid every 30-40k miles should keep everything in order, and popping off the cover every 70-100k miles for peace of mind should suffice.

I saw all of the discussion about torque values (anywhere between 20-30 ft-lbs for the rear cover) so I chose 27 ft-lbs. I did not use any adhesive or loctite on the threads and will monitor them. BTW, I used Valvoline Syn 75W-90 fluid. Just my two cents.