Breaking axle bolts

[zstroken]

I have broken the axle bolts the last two passes on the truck. Looking for suggestions to the cause of this.

I know there is a stud kit available, but is this pretty common? I know of some that have broken them, granted I put used bolts in as that was all I had. I just have worn out bolts or??

[kxhonda]

I was having trouble with my axle bolts as well. I was having a hard time keeping them tight and eventually I started snapping them off. After looking at them I noticed that they were stretched up by the head of the bolt. So I ended up putting in new bolts with loctite but they still loosen up after every pull. I'm looking for suggestions too.

[zstroken]

Originally Posted by kxhonda

I was having trouble with my axle bolts as well. I was having a hard time keeping them tight and eventually I started snapping them off. After looking at them I noticed that they were stretched up by the head of the bolt. So I ended up putting in new bolts with loctite but they still loosen up after every pull. I'm looking for suggestions too.

How many times did you break them? I have sheared the drivers side bolt at the end of the track at the last two hooks.

[getblown5.9]

With the rear spooled I was having a hard time with mine coming loose from all the vibration of moving it around on pavement at the house and in the pits. I put lock washers on the bolts now and I never have to tighten them anymore.

As for shearing them off, is there a heavier grade bolt that could be used? i assume you are using grade 8 now?

[zstroken]

Originally Posted by getblown5.9

With the rear spooled I was having a hard time with mine coming loose from all the vibration of moving it around on pavement at the house and in the pits. I put lock washers on the bolts now and I never have to tighten them anymore.

As for shearing them off, is there a heavier grade bolt that could be used? i assume you are using grade 8 now?

I think the factory are heavier than a grade 8 like maybe a grade 10??

[rawdog]

i think i saw arp studs on haisleys sight
ARP, AXLE HUB STUDS NUTS DANA 60 DANA 70 DANA 80 AAM Haisley Machine

[zstroken]

Yea, but for $160, not sure if I want to go that route. Just kind of perplexed why it broke them back to back.

Especially when we don't know the tensile strength of the ARP stud.

[Signature600]

Originally Posted by zstroken

I think the factory are heavier than a grade 8 like maybe a grade 10??

I think you're right Dan...I have heard of people having them come loose, never has happened to me, or anyone local that I've helped out.

No help
Chris

[getblown5.9]

Originally Posted by zstroken

I think the factory are heavier than a grade 8 like maybe a grade 10??

I was fixing a broken posi in mine a few years ago and snapped a few of the stockers off with a little 3/8" drive impact gun turned way down...so i tried by hand and snapped some more off and I wasn't really torquing them that tight. I figured they must have been fatigued so I went and picked up some grade 8 from the local bolt supplier, and once i added lack washers I haven't had an issue.

[zstroken]

ARP 200-3401 - ARP Disc Brakes - Overview - SummitRacing.com


Of course they are on back order. One thing about the grade 8 bolt is they are thru hardened I think, so that could make them more brittle, but it may be some added strength. I have found some grade 12 bolts.

[GOT-Torque]

I just welded mine on...

[RyanB]

I have seen some guys use an L9 Allen Head bolt or standard hex head....no issues and its quite a bit stronger than a grade 8 (180,000-190,000psi vs 150,000psi for a grade 8) and they can be picked up at most fastener places.

[kmkdiesel]

for an appilcation like this grade 8 bolts and stronger are actually worse then weaker bolts reason being, grade 8 bolts and stronger have no flex to them so they just snap, the weaker bolts have some flex to them so they do not snap they flex alittle.

[zstroken]

Originally Posted by kmkdiesel

for an appilcation like this grade 8 bolts and stronger are actually worse then weaker bolts reason being, grade 8 bolts and stronger have no flex to them so they just snap, the weaker bolts have some flex to them so they do not snap they flex alittle.

While I agree that the softer bolts can flex, I think when they are in a sheer load such as the axle bolts, you want something as hard as possible.

[getblown5.9]

Originally Posted by zstroken

While I agree that the softer bolts can flex, I think when they are in a sheer load such as the axle bolts, you want something as hard as possible.

this is what ive been told as well...some applications are better to use a grade 5 over grade 8...but not in sheer load.

[RyanB]

that is very true! Sometimes going with the strongest setup isn't always the best. A buddy of mine up here that pulls with a blown Kieth Black Hemi in his 2wd truck, and back 10 years ago he found that because of the power he was making he actually started to flex the crank and with studs he would actually break the crank. He then went to bolts which gave him a bit of flex and never broke a crank again and also never caused any other side effects to the motor!
I am wondering if you (zstroken) havn't bent an axle and its causing them to snap or even a bearing starting to go in the hub could cause some minor wobbel and could be causing the issue.

[zstroken]

Originally Posted by RyanB

that is very true! Sometimes going with the strongest setup isn't always the best. A buddy of mine up here that pulls with a blown Kieth Black Hemi in his 2wd truck, and back 10 years ago he found that because of the power he was making he actually started to flex the crank and with studs he would actually break them. He then went to bolts which gave him a bit of flex and never broke a crank again and also never caused any other side effects to the motor!
I am wondering if you (zstroken) havn't bent an axle and its causing them to snap or even a bearing starting to go in the hub could cause some minor wobbel and could be causing the issue.

I suppose the axle tube could be an issue, nothing has really happened to change hopefully.

Hopefully just bad axle bolts. They aren't uncommon to break, as haisleys sell an upgraded part, and I know others who have broken them.

[HIGH TECH RAM]

How about a locking fastener.

[zstroken]

Originally Posted by HIGH TECH RAM

How about a locking fastener.

Locking fastener? Like a lock washer or such?

[HIGH TECH RAM]

Not sure if they make axle bolts but we use them on a friends nitro harley. They will not come loose
World's Best Locking Fasteners Locking Nuts and Bolts STAGE 8