Suspension Bolt Sizes?

[Jeffh555]

If anyone needs a bit to open a hole from 9/16 to 5/8 or 3/4, these bits are the absolute shit. They work like a charm, last forever, and produce a nice surface finish and a round hole. They aren't cheap however.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Can you use them in a hand drill, or does the part need to fit in a drill press/mill?

 

[Wisconsinite]

my problem with these are some holes i could only drill through from one side. could i go through both sides or am i missing how these work. because it said drill distance was only like 1.5 inches. maybe i am missing something

You can drill through.

 

[Wisconsinite]

Can you use them in a hand drill, or does the part need to fit in a drill press/mill?

Hand drill, just go slow.

 

[chaplinfj60]

Hand drill, just go slow.

i think i see where i mis read the drill area is 1.5 inches not the length... thanks

 

[mobil1syn]

Unless the bolt gets loose, or the friction force is overcome. If shear didn't matter no one would care about grip length.

if the friction force of a properly torqued 3/4" bolt is overcome, youve got serious problems.

the rock crawler world just recently started caring about grip length because of the carry over from dezert racing and their fancy hardware. i am not saying to completely ignore it but to think that you are going to get a 'cheap' bolt held to tight tolerances is dumb. build your mount with flexibility, modify the hardware yourself or spend the money for a high tolerance bolt.

 

[Blase]

The question on bolt size is not just an easy generic answer IMO. A high HP rock bouncer or ultra 4 car with heims will need a large bolt for a number of reasons v/s a trail jeep with Johnny Joints or a light weight Toyota with gearing and leaf springs or even a trail buggy with heims.

1) there is NO give in a heim joint like the Jeep and Toyota in my example. The rubber in those joints is going to greatly reduce the chance of the bolt shearing because it has to compress the rubber which absorbs some of the force required to shear a link bolt.

2) HP obviously the roc bouncer and ultra 4 car the HP to create the force required to shear a bolt.

3) weight of the rig. The light Toyota may not weigh enough to shear a long bolt if it lands on the link like the heavier Jeep or Roc bouncer.

4) How you use it. Roc bouncers slam into ledges to get up them v/s the 200:1 Toyota that is going to crawl most of what it wheels. Likewise a Ultra 4 car is going to run into all kinds of things in the desert and roc trails at speed v/s a trial buggy that slowly cruises over those same obstacles.

5) Maintenance! If link bolts are kept tight they are less likely to be damaged or cause damage to the link mounts.

6) Proper sized link brackets. A lot of the link tabs you buy today or even more in the home made ones have out of round holes or over sized holes. That can greatly add to the stress on the link bolts. Same holds true for the width of the link brackets. If the bracket is way over sized and requires the bolt to squeeze it closed to tighten on the joint it will not be as strong as a bracket that is the right size. Having to over torque the bolt to close the bracket and/or having the sides of the bracket not fully contact the joint cause they are bent in / \ \ / weakens the bolt.

EDIT: 6A) the proper bolts is also important as Mobil1syn mentioned above!!!

7) With heim joints the bigger the joints the longer they seem to last longer for those of us that wheel in wet conditions.....so bolt strength may not be the only reason to run a larger bolt/ joint

So can 5/8 link bolts work.....sure! My last buggy and its twin built at the same time have been out wheeling for over a decade with 16MM link bolts using johnny joints top and bottom. LS, 1 tons, 45+ steering, Sticky 39"-42" tires and we aren't the type to use HP to get up something unless we have to. So for us it worked. Neither has ever broken a bolt. Guy I sold mine to found a couple bent bolts while doing maintenance. ALL of the bent bolts were lose. Once changed and tightened properly he hasn't bent another one yet.

All of that said. For the type buggies I like to build and terrain I prefer to wheel I like to use 3/4" lower and 5/8" (3/4" is way over kill but nice to run all the same joints some time) upper is what I like to use.

 

[RustyC]

Caterpillar 3/4"-10 zinc coated bolts. Couple of options depending on tab thickness and 2 5/8" joints. I chose to use 3/4" on all my lowers because I know myself and one day I will get frustrated and crash it all into a rock. I also added internal hex weld washers to the outside/bolt head side of the tabs. I will torque the locknuts on the inside where they are hopefully less likely to get hit.

Trust me the CAT logo will be turned the correct way after paint!

 

[arse_sidewards]

if the friction force of a properly torqued 3/4" bolt is overcome, youve got serious problems.

the rock crawler world just recently started caring about grip length because of the carry over from dezert racing and their fancy hardware. i am not saying to completely ignore it but to think that you are going to get a 'cheap' bolt held to tight tolerances is dumb. build your mount with flexibility, modify the hardware yourself or spend the money for a high tolerance bolt.

And the desert racing world mostly only cares because they're cargo culting the road race car world (who themselves are cargo culting aviation). Grip length doesn't mostly doesn't matter when all your shit needs to be clown shoe sized to heave enough bearing area to yield a reasonable service life. And of course the rock crawlers cargo cult this too so then they bend/break all sorts of shit instead of popping an easily field-replaceable rod end.

 

[RustyC]

instead of popping an easily field-replaceable rod end.

I never want to fail a suspension joint. The potential resultant damage is off the chart.

Link leaves the chat > axle housing flips with excitement > shocks and driveshaft go full mosh pit > then all that is left is a brake line that thinks it's a hero because it lives in the shadow of the limit strap.

That is if you were lucky enough not to pole vault and barrel roll like a cop dodging acorns your way to a DNF.

 

[arse_sidewards]

I never want to fail a suspension joint. The potential resultant damage is off the chart.

So you'll just tear a mounting tab (if tension load) or pretzel a link (if compression load) instead and the axle will wind up in the same place with the same results.

Would you rather break a tie rod end or a steering knuckle/box/pitman?

 

[RustyC]

So you'll just tear a mounting tab (if tension load) or pretzel a link (if compression load) instead and the axle will wind up in the same place with the same results.

Would you rather break a tie rod end or a steering knuckle/box/pitman?

Or maybe it takes the hit and doesn't fail? or the tabs deflect and is found on inspection?

I would rather live in that sweet spot between a component that is adequate enough and heavy overkill.

I had to make the tie rod or steering box decision in my build. I chose steering box as I am limited to options that fit my needs. Everything downstream I can design to hold up. The sector shaft shearing is a concern but I'm betting it fails in a high load situation not cruising down the street surrounded by busses full of nuns.

 

[94toytruck]

So you'll just tear a mounting tab (if tension load) or pretzel a link (if compression load) instead and the axle will wind up in the same place with the same results.

Would you rather break a tie rod end or a steering knuckle/box/pitman?

Neither, that's why I build my trash to not fall apart.

Lets just say I used some hardware or a joint that fails and I'm actually using the rig not driving through a Denny's parking lot at 5mph looking for a spot. That bolt or rod end that fails at 40mph through some whoops or railing on a hill or whatever just cost me a ton of money. Potential damage to shocks, drive line, plumbing at minimum. Cause I built in a weak link?

 

[arse_sidewards]

Guys. You’re missing the fucking point.

Rock crawling shit is rife with properly shanked bolts in 1.25 heims in 3/8 plate tabs welded to an XJ. Doing those sorts of combinations is just dumb.

And nothing that can take even the slightest amount of wheeling is gonna fail on the street. Save that dumbass pearl clutching for Reddit.

You can’t not build a weak link. You just don’t know where it is.

 

[HYDRODYNAMIC]

If anyone needs a bit to open a hole from 9/16 to 5/8 or 3/4, these bits are the absolute shit. They work like a charm, last forever, and produce a nice surface finish and a round hole. They aren't cheap however.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Have these in all the sizes. Great bit. Don't forget about tapered reamers, they can do the same job.

 

[Jeffh555]

Guys. You’re missing the fucking point.

Rock crawling shit is rife with properly shanked bolts in 1.25 heims in 3/8 plate tabs welded to an XJ. Doing those sorts of combinations is just dumb.

And nothing that can take even the slightest amount of wheeling is gonna fail on the street. Save that dumbass pearl clutching for Reddit.

You can’t not build a weak link. You just don’t know where it is.

I think we all missed your point when you said:

And of course the rock crawlers cargo cult this too so then they bend/break all sorts of shit instead of popping an easily field-replaceable rod end.

I actually want to know what you're suggesting. Rock crawlers are retarded, we all know that, but what's the better option?

Very relevant example: My JK front suspension is consists of 1.25 heims bolted to the factory frame brackets. It is currently sitting with a cracket/torn frame lower link mount from the last two trips (back to back weekends, zero prep between, no clue when it started to fail).

I drove it off the trail, onto the trailer. I could have welded it on the trail reasonably easily if need be. If I ripped open a rod end, it would have been ugly.

I already have the .25 thick brackets from Motobilt to replace all that stuff. Yes I'm moving the weakest link, but my goal is to moving it to where I won't see those loads because I don't wheel hard enough.

 

[HYDRODYNAMIC]

All this obsession about bolt strength and torque without questioning the rest of the bolted joint. Some misalignment spacers will crush or shear if you torque the bolt to spec. Some misalignment spacers are undersized too much to pass no go spec and are loose and move under load and or cant handle the bearing load and will wear down and loose bolt tension and friction load. Some tabs will rip open or elongate from the tension. Some tabs will get hammered out by loose laser tolerances and or not enough friction from bolt torque.
One of the main reasons I went with the GoatBuilt subframe was the high strength material and double thickness at the bolted joints. Same goes for the one piece misalignment balls at the rod ends. There is a good chance that the torqued 5/8" bolts will actually have a chance to hold the joint under friction.
I was being cheap when I bought all the upper misalignment spacers and got Ruffstuff on a sale and during mock up noticed how loose and out of spec they were. For final assembly I replaced all of them with I think TMR stainless which had a tight fit in the FK rod end and didn't fall out during assembly. The ball radius was correct and I didn't notice any crushing when torqueing them down. The best part was that the Ruffstuff was over on the over all length and all the tabs had to be pried on and joints hammered in. With in spec misalignment spacer during final assembly it only took a small hit from a deadblow to get the joint into location, didn't even mess up the paint.

 

[TimJus]

dont use cut holes only machined chamfered holes. you dont want your holes to be a cutter blades

 

[arse_sidewards]

All this obsession about bolt strength and torque without questioning the rest of the bolted joint. Some misalignment spacers will crush or shear if you torque the bolt to spec. Some misalignment spacers are undersized too much to pass no go spec and are loose and move under load and or cant handle the bearing load and will wear down and loose bolt tension and friction load. Some tabs will rip open or elongate from the tension. Some tabs will get hammered out by loose laser tolerances and or not enough friction from bolt torque.

Don't forget all the flat plate tabs mounted in dumb ways that subject them to bending loads on their weak axis.

Bonus points if it bends into a new position that then binds something else.

dont use cut holes only machined chamfered holes. you dont want your holes to be a cutter blades

Yet another thing that is neither necessary nor cost effective on any vehicle not going to space.

I get it if you're GM and you have a production line tooled up to make shit and you just wanna make one teeny little tweak to get you an extra 1% but people doing that shit on 1-off builds are doing it for the circle jerk bling factor. If they really thought they needed it they'd up the size of some component or otherwise tweak the design to be stronger before any turd polish is applied.

I think we all missed your point when you said:

I actually want to know what you're suggesting. Rock crawlers are retarded, we all know that, but what's the better option?

Very relevant example: My JK front suspension is consists of 1.25 heims bolted to the factory frame brackets. It is currently sitting with a cracket/torn frame lower link mount from the last two trips (back to back weekends, zero prep between, no clue when it started to fail).

I'm saying a 1" joint would have snapped your bracket just as effectively but there's at least a chance it'd have just bent a shank instead (probably still wouldn't have though).

You're gaining literally nothing by running a joint that's 20x stronger than your next weakest link that you don't get by running a joint that 2x stronger or 5x stronger. You don't see people building 1480 driveshafts for Suzukis.

I drove it off the trail, onto the trailer. I could have welded it on the trail reasonably easily if need be. If I ripped open a rod end, it would have been ugly.

And if you'd have wheeled it a little bit harder and torn the bracket clean through you'd have had the same ugly failure.

Why is this so hard to get?

 

[mjlogan88]

While we're off track what about considering a different way to attach the link. Instead of the typical double shear bracket with a bolt running perpendicular to the load path, how about something like this

Obviously it would be some sort of custom made joint with misalignment for the application. But why not put the bolts in tension as they are supposed to be? Got to be a reason you only see bolt-through joints in light automotive applications, while heavy applications use arrangements like pictured.

 

[Bebop]

While we're off track what about considering a different way to attach the link. Instead of the typical double shear bracket with a bolt running perpendicular to the load path, how about something like this

Obviously it would be some sort of custom made joint with misalignment for the application. But why not put the bolts in tension as they are supposed to be? Got to be a reason you only see bolt-through joints in light automotive applications, while heavy applications use arrangements like pictured.

if a 3/4 bolt does the job for a trophy truck, what are you gaining by going to this complex contraption?

 

[mjlogan88]

if a 3/4 bolt does the job for a trophy truck, what are you gaining by going to this complex contraption?

If a bolt ends up in shear, the job is not being done properly. There’s reference in this thread from “in reality” the friction force fails and the bolt ends up in shear. This is a fail due to prep (my vote and agree with you) or a fail due to design.

If it is in fact a fail due to design and a 3/4 fine thread bolt doesn’t have the clamping force to keep a joint tight, It may be worth another look at the joint arrangement. Namely, one that is designed to be in shear at the pivot

Really it’s just a thought outside the box

 

[arse_sidewards]

Obviously it would be some sort of custom made joint with misalignment for the application. But why not put the bolts in tension as they are supposed to be? Got to be a reason you only see bolt-through joints in light automotive applications, while heavy applications use arrangements like pictured.

I think a lot of it is driven by what's easy and cheap to design and what's easy and cheap to assemble repeatably in volume on an assembly line or what once was (because the companies designing these things aren't gonna pay people to revisit what works unless they absolutely need to).

People designing and building shit they care about (i.e. our personal builds or people building for a race team they're personally invested in) can get a lot higher consistency (i.e people aren't as likely to phone it in at 4:30) of design work and assembly than the OEMs can so there's a lot less need to have stupid proofing build into the parts.

Kinda like how we prefer threaded plumbing shit that's easy to service and field repair whereas the OEMs love stupid proof snap together shit.

 

[Bebop]

Kinda like how we prefer threaded plumbing shit that's easy to service and field repair whereas the OEMs love stupid proof snap together shit.

Wiggins > AN

Snap together shit FTW

 

[desertPOS]

I ended up talking to someone at Brighton Bolt the other day that was able to spec out their bolts over the phone, and had two suppliers here local to me, one of which I've been to before, but forgot about. The other was the one that only had the black phosphate versions. Stopped by, and they had what I needed in 3/4" fine thread yellow zinc plated - half inch increments. Close enough.

so buy the cat bolts and send them out to be plated

Do you know of any places that will zinc plate a black phosphate treated bolt? If that's even possible, is it at a price point even worth considering?

You should never be torquing against a compliant bushing. There should be a sleeve in the bushing, or you should use a shouldered bolt. I know it is pretty common in the aftermarket, but it's plain retarded.

Agreed. Without a sleeve in the bushing, my point was that it's a good application for a castle nut and cotter pin. Shoulder bolt would be even better. Yes poor design that way, which is all Toyota aftermarket suspension stuff it seems...

F911 bolts are held to tighter shank sizes, 6 point hex, and readily available but they do cost about 3x the price

American Thread F911 & L9

American Thread F911 & L9

www.allensfasteners.com

That's a great link for someone who can't find anything locally

 

[desertPOS]

All this obsession about bolt strength and torque without questioning the rest of the bolted joint. Some misalignment spacers will crush or shear if you torque the bolt to spec. Some misalignment spacers are undersized too much to pass no go spec and are loose and move under load and or cant handle the bearing load and will wear down and loose bolt tension and friction load. Some tabs will rip open or elongate from the tension. Some tabs will get hammered out by loose laser tolerances and or not enough friction from bolt torque.
One of the main reasons I went with the GoatBuilt subframe was the high strength material and double thickness at the bolted joints. Same goes for the one piece misalignment balls at the rod ends. There is a good chance that the torqued 5/8" bolts will actually have a chance to hold the joint under friction.
I was being cheap when I bought all the upper misalignment spacers and got Ruffstuff on a sale and during mock up noticed how loose and out of spec they were. For final assembly I replaced all of them with I think TMR stainless which had a tight fit in the FK rod end and didn't fall out during assembly. The ball radius was correct and I didn't notice any crushing when torqueing them down. The best part was that the Ruffstuff was over on the over all length and all the tabs had to be pried on and joints hammered in. With in spec misalignment spacer during final assembly it only took a small hit from a deadblow to get the joint into location, didn't even mess up the paint.

Like these? All heims and spacers I have are Ruffstuff. I've heard similar before - I don't think I need the high misalignment spacers like this. Off to search TMR's site...

Not sure if it's outside of what this thread is for, but regarding Left Hand and RH heims - I currently have links set up so the jam nuts can be loosened and links adjusted on-vehicle. I think I've heard complaints about that, and maybe should oppose them (RH threads on both ends instead of LH one side, RH on other). I know I'm not explaining that well, but if anyone has any thoughts on that I'd love to hear it. I've got links tacked together now, but getting ready to finish weld soon, so not too late to cut apart and switch things around

 

[gt1guy]

Not sure if it's outside of what this thread is for, but regarding Left Hand and RH heims - I currently have links set up so the jam nuts can be loosened and links adjusted on-vehicle. I think I've heard complaints about that, and maybe should oppose them (RH threads on both ends instead of LH one side, RH on other). I know I'm not explaining that well, but if anyone has any thoughts on that I'd love to hear it. I've got links tacked together now, but getting ready to finish weld soon, so not too late to cut apart and switch things around

I did RH threads on all my lowers and LH threads on all my uppers, just for the reason that if the jam nuts get loose, the links don't change lengths....they just start making a racket you hopefully hear.

It does make adjusting the lengths take a million times longer. But, once dialed in, how often is anyone doing anything more than checking the jam nuts?

 

[YotaAtieToo]

So you'll just tear a mounting tab (if tension load) or pretzel a link (if compression load) instead and the axle will wind up in the same place with the same results.

Would you rather break a tie rod end or a steering knuckle/box/pitman?

Have you ever built or wheeled a rig with 1 1/4" hiems?

No body is building a real crawler or bouncer with the bolt as a weak point.

 

[YotaAtieToo]

I did RH threads on all my lowers and LH threads on all my uppers, just for the reason that if the jam nuts get loose, the links don't change lengths....they just start making a racket you hopefully hear.

It does make adjusting the lengths take a million times longer. But, once dialed in, how often is anyone doing anything more than checking the jam nuts?

Why not just do all RH then?

I do buy into all RH lowers since they see the rock hits. It doesn't seem to matter how tight you get the jam nuts, a few real rock trails and they're loose again. Then, how often are you adjusting lowers?

I don't see why you would do all one way on uppers though.

 

[94toytruck]

Have you ever built or wheeled a rig with 1 1/4" hiems?

No body is building a real crawler or bouncer with the bolt as a weak point.

If he built a rig it would go 20feet into the rocks and break cause the engineered weak point would break

 

[gt1guy]

Why not just do all RH then?

I do buy into all RH lowers since they see the rock hits. It doesn't seem to matter how tight you get the jam nuts, a few real rock trails and they're loose again. Then, how often are you adjusting lowers?

I don't see why you would do all one way on uppers though.

Because I had 8 LH and 8 RH joints. I was planing to do it the normal way right up to when I ordered the links from BentFab. It was on that phone call I made the "call" for RH lowers/LH uppers.