M8 Bolt disaster, some help and advice needed inside...

[Grug556]

Guys how is everybody doing with the awesome oem M8 bolts that hold up the skid plates and braces and various other stuff under the pig. So far even using caution I have broken 3 bolts now. All sheared off at the head. I do the usual drill and extractor. Had one so bad it had to recut it as an M10. Have two more im working on. The hardened steel extractor broke off inside one of them, the other one.... the cobalt drill tip shattered and is wedged up inside it. I am gonna try vise grips on shaft next. You guys have any ideas beyond the usual? Never seen such shit fasteners before. Almost 30-40% failure rate on lower frame stuff.

 

[apc9199]

The single most useful "Broken Bolt Extraction" video I have ever seen. I use this method on everything I can now and it is 10 for 10 so far.

https://www.youtube.com/watch?v=dJfkCj3FWBs

 

[Grug556]

The single most useful "Broken Bolt Extraction" video I have ever seen. I use this method on everything I can now and it is 10 for 10 so far.

https://www.youtube.com/watch?v=dJfkCj3FWBs

Thanks for that vid. Problem I got is the extractor and the drill bit are stuck in both. Ill try again.

 

[Bmnorm2]

Guys how is everybody doing with the awesome oem M8 bolts that hold up the skid plates and braces and various other stuff under the pig. So far even using caution I have broken 3 bolts now. All sheared off at the head. I do the usual drill and extractor. Had one so bad it had to recut it as an M10. Have two more im working on. The hardened steel extractor broke off inside one of them, the other one.... the cobalt drill tip shattered and is wedged up inside it. I am gonna try vise grips on shaft next. You guys have any ideas beyond the usual? Never seen such shit fasteners before. Almost 30-40% failure rate on lower frame stuff.

I torque mine to 8 ft-lbs. I've removed and re-torqued 4 times now over the last 27k miles and 22 months. No failures to date. I applied anti-seize to all of them on first removal.

8 ft-lbs is very easy to exceed. I use a 1/4" drive torque wrench for these.

** This is actually for the m6 bolts that use a 10mm socket to drive.

The M8 bolts uses a 12 mm socket to drive and I torque those to 21 ft-lbs. Also no failures.

 

[02SE]

It sounds like the fasteners have been over-torqued.

I had the same fasteners on my 3rd gen, no issues in 22+ years. Of course I was the only person to ever service the 3rd gen.

 

[Grug556]

ok heres the part. I was wondering is it safe to take off this crossmember while vehicle is on stands? I cant drill it out further in this position as i need it on a drill press. Only way to do this is to take out the entire cross bar. Looks like its held in with four bolts in center and 2 nut and bolt ends on each end. See picture

Need to know if this is safe to remove and easy to get back on? Am i missing any bolts other than 2 per ends and 4 in center? Any problems with these? Also run the risk of snapping the 4 center ones during removal. Ugh ugh ugh!

 

[Jeremy556]

ok heres the part. I was wondering is it safe to take off this crossmember while vehicle is on stands? I cant drill it out further in this position as i need it on a drill press. Only way to do this is to take out the entire cross bar. Looks like its held in with four bolts in center and 2 nut and bolt ends on each end. See picture

Need to know if this is safe to remove and easy to get back on? Am i missing any bolts other than 2 per ends and 4 in center? Any problems with these? Also run the risk of snapping the 4 center ones during removal. Ugh ugh ugh!

I would hit the cross member bolts with oil, heat, and smack the crap out of them with a hammer before removal.

You'll need to remove the nuts or bolts (I forget which, accessed through the bottom of the cross member) securing the trans mount to the cross member and support the the trans with a jack when you remove that cross member.

Something I have done, that you may find helpful: I have had to drill out just about all of my skid mounting holes over the years and have been replacing them with rivet nuts. They are zinc coated so much less rust problems, and if one gets stuck, you can simply hammer it through from the bottom and it breaks off easily, then just 2 minutes to replace the rivnut.

Also, do you have, or know anyone with a welder? Welding a nut on there would probably get it out without too much trouble. The heat from the welder usually breaks the rust bond.

 

[Grug556]

I would hit the cross member bolts with oil, heat, and smack the crap out of them with a hammer before removal.

You'll need to remove the nuts or bolts (I forget which, accessed through the bottom of the cross member) securing the trans mount to the cross member and support the the trans with a jack when you remove that cross member.

Something I have done, that you may find helpful: I have had to drill out just about all of my skid mounting holes over the years and have been replacing them with rivet nuts. They are zinc coated so much less rust problems, and if one gets stuck, you can simply hammer it through from the bottom and it breaks off easily, then just 2 minutes to replace the rivnut.

YEah agreed on what you said. The problem i have is that I cant drill them out as I have hardened metal pieces of the broken extractor bits wedged in them These werent cheap bits so they are quite hard. My cobalt bits wont drill it. Thought easiest way would be removal of the crossmember and use of a drill press.. But the transmission sounds a problem. I am not sure how to support it.

 

[Too Stroked]

Got any talented welder friends? They can weld a nut to what's left of the fastener, and you can then back it out with a wrench.

As for what caused the mess, I too would agree that somebody got a bit frisky with an impact - maybe at the dealership - and weakened the bolts. Personally, I apply Never Seize to everything I regularly remove and replace.

 

[Grug556]

Got any talented welder friends? They can weld a nut to what's left of the fastener, and you can then back it out with a wrench.

As for what caused the mess, I too would agree that somebody got a bit frisky with an impact - maybe at the dealership - and weakened the bolts. Personally, I apply Never Seize to everything I regularly remove and replace.

Last year I got rid of my welder.. perfect timing. It was a Lincoln stick but might have worked ok. Those bolts have never been removed there, so last person to tight then likely some guy in Japan.

 

[seatia]

Guys how is everybody doing with the awesome oem M8 bolts that hold up the skid plates and braces and various other stuff under the pig. So far even using caution I have broken 3 bolts now. All sheared off at the head. I do the usual drill and extractor. Had one so bad it had to recut it as an M10. Have two more im working on. The hardened steel extractor broke off inside one of them, the other one.... the cobalt drill tip shattered and is wedged up inside it. I am gonna try vise grips on shaft next. You guys have any ideas beyond the usual? Never seen such shit fasteners before. Almost 30-40% failure rate on lower frame stuff.

This might save you if there is enough sticking out for vice grips.
Keep in mind that welding is by far the best option. Tig is best.

With an oxy/acet torch, heat up the broken bolts to deep cherry color and then spray with cold water. That should break the rust free. Then liberally soak bolt in good fluid. The whack them as hard as possible with a hammer. That will help break them loose. (If you ever have a tough bolt ALWAYS whack them hard first)
Then try the vice grips, but just wiggle them back and forth to free them more until they are out.
Repeat if needed.
I've replaced mine with 316 Stainless and Always use a good an antiseize as you can afford. Tef-Gel is the best I've found, but is crazy expensive.

The OEM bolts are self tapping and therefore very hard. When frozen, they will snap rather easily. They are also harder to drill. Drill with cobalt bits at a very slow, high pressure. A good cutting fluid such as made by Rigid, will help to keep the bit cool.

Frankly, I would just drill and tap for M10 and replace all with SS and antiseize

 

[repo]

Guys how is everybody doing with the awesome oem M8 bolts that hold up the skid plates and braces and various other stuff under the pig. So far even using caution I have broken 3 bolts now. All sheared off at the head. I do the usual drill and extractor. Had one so bad it had to recut it as an M10. Have two more im working on. The hardened steel extractor broke off inside one of them, the other one.... the cobalt drill tip shattered and is wedged up inside it. I am gonna try vise grips on shaft next. You guys have any ideas beyond the usual? Never seen such shit fasteners before. Almost 30-40% failure rate on lower frame stuff.

Did that to one of them in the excitement right after I bought mine (used obviously). I think it might take welding a nut on top of the broken extractor probably.

How to avoid problems:

1. Liquid Wrench (even better: KROIL) from any and all angles for days. Maybe even some heat applied on it first so it sucks the penetrating oil up in them threads good, if they still feels snap-happy. Then wire brush, thread chaser, so forth and so on the holes. Splurge on some brand new bolts, life is too short for gross looking skid bolts.

2. ANTI-SEIZE.

3. Always removing the skids yourself before you take it to a shop nom sayin.

 

[Grug556]

Did that to one of them in the excitement right after I bought mine (used obviously). I think it might take welding a nut on top of the broken extractor probably.

How to avoid problems:

1. Liquid Wrench (even better: KROIL) from any and all angles for days. Maybe even some heat applied on it first so it sucks the penetrating oil up in them threads good, if they still feels snap-happy. Then wire brush, thread chaser, so forth and so on the holes. Splurge on some brand new bolts, life is too short for gross looking skid bolts.

2. ANTI-SEIZE.

3. Always removing the skids yourself before you take it to a shop nom sayin.

yeah thats more or less how ive been doing it, these bolts were just oem that have seen a couple years of salt on them during winter. Corrosion is pretty bad.

 

[Jeremy556]

YEah agreed on what you said. The problem i have is that I cant drill them out as I have hardened metal pieces of the broken extractor bits wedged in them These werent cheap bits so they are quite hard. My cobalt bits wont drill it. Thought easiest way would be removal of the crossmember and use of a drill press.. But the transmission sounds a problem. I am not sure how to support it.

It doesn't take much. Floor or bottle jack are perfect, but even a piece of wood, jackstand, milk crate, pretty much anything that can support 150 lb or so is fine, just put it under the trans pan.

 

[CutthroatSlam]

yeah thats more or less how ive been doing it, these bolts were just oem that have seen a couple years of salt on them during winter. Corrosion is pretty bad.

Was wondering how the hell this could happen, but then I looked and saw Canada in your profile and knew it was due to road salt. I feel for those who are in areas where they salt the roads.

 

[Humble Leader]

Was wondering how the hell this could happen, but then I looked and saw Canada in your profile and knew it was due to road salt. I feel for those who are in areas where they salt the roads.

there must have been some over torqueing going on. my 2012 is 10 years old, road salt every year, and never had a broken bolt after countless oil changes after 159k miles.

I did replace all the skidplate bolts proactively because I replaced the skidplates in early 2021 but the bolts were fine.

I don't do my own oil changes but I am regularly crawling under my truck to have a look underneath. I'll randomly check some bolts for tightness and make sure no bolts have worked their way loose.

 

[Mike Beyers]

Unless you get the extractor and drill bit pieces out, it won't matter where or on what type of drill you're drilling. Those two things are as hard, or harder than the drill you're using. You have got to chip them out somehow, or like it's been said, go with the weld a nut on technique. I know it sucks, because it's not an easy place to work, but you might want to try that before removing that cross member. If you HAVE to you can try solid carbide drills (available at McMaster Carr) to remove the broken pieces. However, be advised, they are as brittle as glass, and if you break one of them off, it will need to come out with force, or by burning it out on a tap extractor.

 

[Whippersnapper02]

I'd have someone weld a nut onto those if possible. For next time, invest in reverse twist drill bits and a good set of extractors.

 

[Bobby12many]

Never start a fastener with a wrench. Impact off, never impact ON. Words to live by.

Either you have exceptionally bad luck or those M8 bolts were ugga-dugga'd when reinstalled.

That said, the suggestion of getting a nut welded is a good one - beyond giving you some purchase on the remaining stud, the heat that a welder will send through that fastener will definitely help break the bond.

Hope you are able to get it licked!

 

[Grug556]

I'd have someone weld a nut onto those if possible. For next time, invest in reverse twist drill bits and a good set of extractors.

I have a set, they are IRWIN, decent stuff. Have reverse twist cobalt bits as well.