Spring bolts
 

Just blasted the disassembled springs for my 39 pickup restoration and noticed the grease grooves in the leaves. How does one inject the stuff? Also, I will be replacing the center bolt and will check the strength of various bolts. I am leaning toward an AN aircraft bolt but need to know the direction of stress for selection of proper type bolt. Shear or tension?

Re: Spring bolts
 

On my '41 the original bolt had a grease fitting to force grease between the leaves.

Re: Spring bolts
 

If you want to lube the spring you will need the original nut with the grease fitting. The spring bolt requires very little strength there is almost no load on it once the spring is installed. It's main function is to hold the spring together when it is not bolted in place and to center the spring when mounted. The spring lube is not grease but a special spring lubricant. Grease will make a mess out of it and plug the grooves.

Note: edited to correct, there is not a hollow bolt, it is lubed through a special nut with grooves in it.

Re: Spring bolts
 

Where would I find such a proper bolt and spring lube?

Re: Spring bolts
 

Hi Everyone, JRHASZARD, Roy Nacewicz at http://www.fordscript.com/ford_bolts/products.html has them, see the bottom of page 12 and the top of page 13 in the first catalog.

Re: Spring bolts
 

John, I don't think those bolts were all that special. They may have had a square or round head that would fit into the hole provided in the cross member to center the spring pack, maybe a center hole as mentioned, or possibly a slot or two along the sides for grease to flow in through to each leaf. Or since this bolt would be a slightly loose fit in each spring leaf hole, the grease may just flow naturally between the bolt at each leaf from the pressure of the grease gun. A long threaded nut that would fit on bolt threads, and provide for mounting of a zerk fitting on the other end. The most critical feature might be finding the correct length that you will need for the number of leaves in your spring pack.

Re: Spring bolts
 

Guys, you can not use grease to lubricate these springs! Earlier post by Kurt in NJ:

"It's not for grease, it's for spring lube, once greased with grease the passages will be clogged and the lube won't flow to the tips of the leaves, spring lube is about 75% light oil(atf)25% talc, and originally a bit of ground asbestos(used in a dedicated grease gun, shaken before use)"

"The center bolt nut has a passage, the spring leaves have a notch next to the centerbolt, the leaves have a shallow depression in the center to guide lube to the tips----grease won't flow like the thin spring lube all the way to the tips of the leaves where the lube is needed most."

Re: Spring bolts
 

Re: Spring bolts
 

I have never seen a hollow spring bolt. I have seen sacks of NOS bolts from a friend's collection of parts from 3 Ford Dealers stock which he bought out. The fronts are smaller in diameter then the rears and have a square head to fit into the x member. The NUT is special and has 2 grooves to allow lubricant up through the gap between the bolt and the hole. You might check with All Ford Parts in CA as I think he bought many of these after my friend passed away. There is a Sorensen video of the factory putting the tin covers on springs and then lubing them via this nut after the spring was assembled.

Re: Spring bolts
 

I believe deuce roadster is correct, the nut has the grease fitting. I will modify my original post to correct it (senior moment).

If you are not concerned about being 100% original and/or using the spring lubricant these parts are not needed. The original bolt had a square head, I assume you could modify a bolt to fit the square opening in the frame crossmember. The parts book calls it out as a 5/16-24 x 5 1/2 bolt.

Re: Spring bolts
 

I have been using grease in the spring bolt of my '41. What is a brand of spring lube I should use? Also, should I try to clean the grease out as best I can? Still learn'in I guess.

Re: Spring bolts
 

I'm not sure where you can get the spring lube or what would work as a substitute. I don't use it myself, I use spring liners. I would suggest you start a new tread and ask where you can find something that would work. It would be interesting to see what folks are currently using.

Re: Spring bolts
 

Re: Spring bolts
 

Fellers, many thanks for all the very helpful comments and shared wisdom.

Re: Spring bolts
 

Another option for spring lubrication (not using the zerk nut) is SLIP. It is applied to the spring leaves during assembly.