I'm working on stripping down my 4X4 so I can get this truck back on the road.
I have some questions about bolts though.

I have lost quite enough skin off my hands trying to break some nuts loose. I have decided to go ahead & just cut the pesky little buggers off.

Are the bolts readily available for new purchase?

The bolts I will need are the front bumper & rear bumper bolts. I may need the bed bolts also.

 

<cr>
Yes. You can get different sizes and lengths.

 

Do I have the buy the bolts from the dealership or could I just go into any hardware store & buy grade 8 bolts?

 

I bought bumper bolts for the front from ford. It was $4 and change for them w/ the speed clips, had to be ordered though so I had to wait a couple days for them.

 

Id just got to a Tractor Supply if there is one in yar area or some simler store and buy bolts by the pound much cheaper. General rule is grade 8 is a shear bolt used on farm machinery and the such to protect drivelines. Grade 5 is a frame bolt used on car and truck frames. garde 1or 2 there really the same is alight duty general purpose bolt. either grade 5 or grade 8 would work for you. grade 8 bolts are more brittle then garde 5 so id use grade 5. they are also a bit cheaper. If there was garde 8 bolts in there tho best replace them with garde 8. ya can tell by counting the hash marks on top of the bolt then adding 2. if ya have 3 hash marks thats a grade 5 six hash marks thats a 8 no hash marks thats one or two.

 

I have for many years believed what redneckmechnic posted.

I WAS WRONG.

Read em and weap.

http://www.rockcrawler.com/techrepor...ners/index.asp

 

Whoa there.. redneckmechanic is 100 percent
absolutely correct.

 

Ford Pilot,

Two years ago I would have agreed and argued about it but I was wrong then and I'm right now. I provided a link which explains it. Can you tell where I'm wrong AND back it up with facts? I'm not trying to say I'm smarter and you are wrong. Like I said before I have told many people the same thing he said. I was wrong. I know better now.

Did you even read the link I provided or do you just know that I'm wrong cause you believe like I used to?

 

I did read your tech paper and it was very
well done. I applaud you for investigating
the engineering and science of fastners..
something most people are never
exposed to and never think about. Keep
up the good work.

 

Redneckmechanic wrote

"General rule is grade 8 is a shear bolt used on farm machinery and the such to protect drivelines."

Did he mean that the bolt will shear and protect the driveline as in a shear pin or that it won't shear. That is what i was trying to clear up. I have heard it said many times use a grd 5 for suspension because the grd 8 will shear. That statement is absolutely false. The grd 5 will shear before the grd 8.

Redneckmechanic wrote

"grade 8 bolts are more brittle then grade 5 so I'd use grade 5."

This is a correct statement but the difference is not going to effect the way we use them. You have to get into much higher loads and bolt grades before that becomes a factor.

Redneckmechanic did not say that I just wanted to clear up the brittleness part. So many people have heard that and I wanted it to be clear.

 

Darkman - good link!

Grade 8 does show to be superior to grade 5, but it's clear that grade 5 is good enough for many applications. Winches, towing, any application where failure can be dangerous, of course grade 8 is the only way to go. I learned long ago that the grade 2, (or what ever the hardware stores sell with no hashmarks) snap off really easily. I don't use them at all for anything 1/4 inch or larger. I'm not sure that grades 5 or 8 are even availabe for sizes less than 1/4 inch.

marc

 

well i guess i have to clear up a little but what i said. First darkman thanks for providing the great link. Now here it goes first a shear bolt is desgined to shear/break in order to protect the drive line in the case of a jam up etc etc. Grade 8 are normally used there since the hole for the bolt is drilled through the driveshaft thus weekening the shaft so ya want as small as a hole as possible thus the reason a grade 8 is used. Now the reason that a grade 5 is recomend for most applications over a grade 8 on truck frames is quite simple. truck frames like it or not are made from a soft metal, in order for the grade 8 bolt to be stronger it must be toruqued down tighter then a grade 5 this extra torque can and will deform the frame or pull the bolt head thro the frame over time. Reason is the bolt is streched slightly thus it is a mini spring with a lot of clamping force. If the bolt is not torqued down properly it will shear well before its rated carry load this is why i used the term brittle. This goes for all gardes of bolts. this is the main reason that oems use grade 5 it is more then strong enough for the application and will not defrom the frame over time. the reason why grade 8 bolts normally shear on suspension parts is they are not torqued down tight enough. In plain english a grade 8 bolt that is say hand tight versus a grade 5 bolt torqued down properly the grade 8 will fail much quicker then the grade 5. So if you need extra strenght then use a grade 8 bolt but you must make shore that it is torqued down properly and stays torqued down. I have seen many bolts torqued down propelry loosen up if the metal they are holding together is to soft and the bolt will deform/sink into the metal. The next thing you no that bolt shears when it shouldnt casue now it is not torqued down properly. This is the reason I recomend grade 5 for the bumpers and bed bolts. the bed bolts go thro sheet metal cant and wont ever be able to torque them down tight enough with out bending the sheetmetal bed. The bumper brackets on these trucks came stock with grade 5 and even in a wreck a grade 5 bolt will not shear before the hole it goes thro is stretched way out. Plus the bumper brackets are made out of a soft metal and would loosen up if a grade 8 bolt were used. Hope this clears things up and if not well say so and ill do my best. If anyone disagreas say so and back it up with somthing. We are all here to learn. By the way i got this information from school I go to school for ag mechanics and if any of ya are or no farmers i think ya will agree that they use the most bolts of anybody out there of all diffrent grades and applications. along with the most creative inventing of mechnical means to get somthen done easier.

 

Good post Redneckmechanic,

I understand what you are saying and agree that a improperly fastened grd 8 is worse than a properly fastened grd 5. I run into a problem on the frame. I am using fine thread bolts and where I get mine you can not buy a grd 5 fine thread. I was told that they don't make them. This is 7/16's and larger. I think we are on the same track. I advocate using flat washer on the soft frame rails as this helps to distribute the load. I also recommend Loctite on critical fasteners along with periodic inspections. I also use Nylocks.

Grd 5 is fine for probably 90% of the time. Remember if you remove a riveted part Ford recommends a bolt one size larger.

 

I dont see why ya couldnt use a course thread bolt. on smaller bolts more threads make a diffrence but on the large bolts i wouldnt think it would efdfect it to much. Thats a good tip about the rivet replacing. i did not no that but it makes sense.

 

I believe it is all related to holding power. Fine thread equals more surface area per inch of threaded bolt. More surface area equals more holding power. You would have to use a larger bolt to achieve the same holding power if you use coarse thread. Most suspension related fasteners use fine thread as do many other critical fasteners.