Broken rear shock stud. Grade 8 or 5?

[jeannies_driver]

grade 8 is not always the preferred strength... as it can snap in shear where a lower grade bolt will flex.

Myth ! By the time that grade 5 bolt bends the grade 8 isn't even thinking of flexing. I use to think and hear the same thing but it's wrong. The difference is only like 30ksi between the 2 ?

Here's an explanation of 5 vs. 8 and their yields and how to figure out exactly what any given bolt can hold before failure. http://www.rockcrawler.com/techreports/fasteners/index.asp

Either way, you could have used a 1/2" grade 5 bolt and it would have been more than sufficient for a shock mount. Also you might want to weld it to the plate. Eventually it will start to move, rattle and wear out.

 

[sunburned]

Wait, so you are welding a bolt straight to the axle tube for a shock mount? Why not get one from ruff stuff or JKS to replace the stock part? Will be much stronger, especially the ruff stuff double shear.

 

[jeeperjohn]

Why?

Because why take even a little bit of a chance to save a few cents?

 

[austinaubinoe]

OH your welding on all new mounts, might as well do it right:

 

[XJLI]

update:

i bought bolts for my shocks, they were grade 5. my jeep exploded.

 

[ROBZ95Xj]

I went to the hardware store to check out the grade 8 stuff. $4.95 a lb ain't too shabby. The other place I always got my bolts charged BY the bolt. I tried to fit a 5/8" x 3 bolt in the bushing but that phucker wouldn't fit. I bet a little grease will get it on. I can still use 1/2" bolts with the shock bushing sleeve instead but can't pre-load the bushing with that.

So i grabbed two 3 x 1/2 bolts and two 3 x 5/8 bolts (and nuts/washers) all for $6. Not bad. We'll see what Joe says when he goes about welding it.

get rid of the stupid metal sleeve

 

[ROBZ95Xj]

i did this

then the grade 5 bolt broke and i did this

you can see everyone lookin at the broken bolt


sadley a kitten died cause i used a grade 5 bolt, so peaple dont ese a grade 5 bolt, use a grade 6.5 bolt, its a perfect balance

 

[ktm racer 419]

Wait, so you are welding a bolt straight to the axle tube for a shock mount? Why not get one from ruff stuff or JKS to replace the stock part? Will be much stronger, especially the ruff stuff double shear.

because the jks mounts are $65 and mine are $4. and mine are stronger anyway.

 

[austinaubinoe]

^ Nice work!

 

[Milford Cubicle II]

First of all, I'm sure grade 5 is plenty strong and it's not a big freakin deal if it breaks anyways.

Also, I too was told by a machinist for a large factory that grade 5 handles the cyclic stress of suspension components better than grade 8.

He could be wrong though :dunno:

 

[vt98xj]

Since you are welding it anyhow, the HAZ will play in the strength of the bolt unless you get the whole mount and axle heat treated to normalize it. The Bolt grade 5 or grade 8 is not likely to break, the weld is the weak point.

But if it breaks again just weld another on.

 

[muddeprived]

Ok funny and serious comments aside, anyone know where I can get a 4" or 4.5" fully threaded grade-5 or grade 8 bolt? Can't find it locally.

 

[RCP Phx]

Seems like it would be cheaper/easier to just replace the stud!

 

[muddeprived]

Seems like it would be cheaper/easier to just replace the stud!

That's my plan, which is why I asked for a fully threaded bolt. Found some on Mcmaster in GRADE EIGHT....lol. Regular bolts only thread about an inch or so and don't allow me to bolt it to the bracket with a nut. So I'm gonna order up two and bolt that thing down. The 2nd will be put aside for when the other side breaks.

 

[RCP Phx]

That's my plan, which is why I asked for a fully threaded bolt. Found some on Mcmaster in GRADE EIGHT....lol. Regular bolts only thread about an inch or so and don't allow me to bolt it to the bracket with a nut. So I'm gonna order up two and bolt that thing down. The 2nd will be put aside for when the other side breaks.

I don't think you understood,the pic is of a replacement shock mount from Dorman products.They are of the shelf at most auto parts stores!

 

[muddeprived]

I don't think you understood,the pic is of a replacement shock mount from Dorman products.They are of the shelf at most auto parts stores!

Oh now I do lol. Sorry. I'm gonna search for a part number but if you know it and feel like tossing it my way, thanks. There's an Advance right down the road so hopefully they carry it.


Edit: found it:

http://shop.advanceautoparts.com/we...-Dorman---Help_5016940-P_N3133_A|GRP2037_____


Thanks for the info. That should work.

 

[garr]

He drilled a hole through the backside of the mount and cut off the stud. Unfortunately he did not have a 5/8" drill bit so we used the 1/2 bolt. Unfortunately, again, the 3" bolt was not long enough so all I had in the bag was a 3.5" grade 5 bolt. He stuck it in there and bolted up the shock. It didn't need to be welded since the mount was like 1/2" thick and held the bolt straight. So if by any chance the bolt does break, I just pop it out and replace it with another.

I did the same thing but with a grade 8 bolt, I only had a 1/2" bit & bolt with me while out on the beach Figured it was better than nothing, I have been meaning to replace it for 2+ years now. It seems to be holding up !

 

[muddeprived]

Fixed it....


http://www.naxja.org/forum/showthread.php?p=245434904#post245434904

 

[xcm]

i think the saying 'it is wut it is' sums up this thread quite well... even thru the 2nd wave of what-if jokes