Stainless Steel Hardware

[ChunkyLover53]

Hello everyone,

I am working on a 30 year old vehicle that has been through a lot but generally seems to be in good order (California truck). I feel like replacing some of the hardware based on its condition and was wondering if its acceptable to use stainless steel hardware. To be clear, none of this hardware will be on or around the engine, transmission, or any other part of the drive train. It is more frame related bolts and other body type fasteners. Will the introduction of stainless steel (or new type of metal in general) cause any issues? Or should I just clean up the original hardware?

Thanks,

 

[p00p]

I would not use SS as a replacement unless it was for interior areas.

 

[ChunkyLover53]

I would not use SS as a replacement unless it was for interior areas.

Gotcha. Thank you very much.

 

[honcho]

OEM automobile hardware is generally of pretty high quality compared to much of what is commonly available. Many enthusiasts scavenge OEM hardware on visits to u-pull-it type junkyards. Alternately, high quality hardware can be obtained from vendors like McMaster-Carr.

 

[BlakeTheCarGuy]

It can cause galvanic corrosion on certain metals. If it wasn’t used originally then I don’t think I’d use it. Maybe just use a little anti seize on the threads to prevent it from seizing instead.

 

[andyvh1959]

Beat me to it, stainless steel threaded connection most often require some form of anti-seize applied to the threads. If not applied and while tightening, galling can occur and cause the connection to seize up, can;t tighten it to final torque, can't loosen it.

Stainless Steel Galling and Its Causes | RG Group

Being aware of galling & taking precautions when using stainless steel parts, you can avoid the hours of headache and rework. Learn more!

www.rg-group.com

 

[LXCam]

I think its fine as long as you follow those guys ^^^ advice. I use a ton of it on certain builds with that caveat.

 

[matt_i]

Stainless steel is worse than a Grade 2 fastener.

And will gall like crazy to a stainless steel nut without careful application of anti-seize.

Imo, stick with OEM, or plated/coated Grade 5 or 8 or DIN equivalents.

 

[nadogail]

I would not substitute Stainless for a Grade 5 if strength is a consideration. There are different alloys, but I don’t know how they compare in strength.

 

[californiaHank]

In general, you want to keep stainless fasteners away from regular carbon steel. They're too far apart on the 'galvanic series', meaning you're going to have corrosion problems wherever stainless and non-stainless steels contact each other.

 

[Stuart in MN]

There are high strength SS fasteners, ARP sells them. However. I agree with the posts above regarding galling.

 

[niget2002]

Oops. Now I need to get new bolts for the shocks on my Harley. I added a set of saddlebag brackets and the bolts that came with the kit weren't long enough. I used stainless thinking they wouldn't rust :/

 

[Neggy]

what are the markings on the bolts you are replacing?

As others have said, anti seize is a must, and that throws torquing them an issue as torque specs are normally for lightly oiled or dry depending on the application

Unless you are going to spend $$$ for special alloy SS, most stainless is just under Grade 5

 

[Bretny]

If the vehicle is in good condition you shouldn't need to replace any bolts. If the bolts do need to be replaced the vehicle is nearing the end of its life and SS hardware wouldnt be worth it. If it's not broken...dont fix it.

Also like stated many times SS galls like crazy. I have literally taken 1/2in hardware out of the bin, tightened it on a piece of equipment, then had to remove it by breaking the bolt because it galled to hell.

 

[joe_padavano]

Commonly available stainless fasteners are low strength (about the same as Grade 3 steel bolts). You can get high strength stainless fasteners, but you need to be sure that's what they are. You aren't going to find them at Tractor Supply.

Totally Stainless sells high strength stainless for automotive applications. Fastenal, McMaster Carr, and other industrial supply vendors have very high strength stainless fasteners for industrial and aerospace use. They won't be cheap.

 

[Jswain]

If you have a lot of bolts/nuts off at a time and they are rusty, first soak them in degreaser, then rinse and chemically remove the rust with vinegar or citric acid or buy a can of evaporust.

Now all you need to do is pick a coating. I like the black oxide coating kit from Caswell. Soak it in the coating for as long as you want then soak it in oil. Your hardware will look brand new as long as the rust didn't physically remove any amount of metal.

Best part is that it is almost no physical work just soaking in a bucket of chemicals. Some antiseeze on the threads when installing and bobs your uncle

 

[LS6 Tommy]

I like the black oxide coating kit from Caswell. Soak it in the coating for as long as you want then soak it in oil. Your hardware will look brand new as long as the rust didn't physically remove any amount of metal.

Best part is that it is almost no physical work just soaking in a bucket of chemicals. Some antiseeze on the threads when installing and bobs your uncle

Caswell makes good stuff. I used to use one of their products for restoring carburetors. Looked just like new.

Tommy

 

[Lightning rod]

I think there is some confusion with SS and mild steel fasteners

(1) SS fasteners should always have anti-seize on them. SS tends to gall so Anti-Seize is a must
(2) SS typically isn't as strong as grade 5 etc used for structural performance and high strength SS isn't really available or cost prohibitive
(3) if SS fastener is used into steel or aluminum (more is found on cares today), there is very little
galvanic corrosion effects because the SS fastener has little surface area compared to the large steel or aluminum parts

(4) if steel fastener is used to fasten large SS or aluminum parts, galvanic corrosion is a much bigger problem

(5)how do I know this?

(6)the transformer and power industry has used SS fasteners into steel, cast iron and aluminum for over 40 years
with almost no issues. In fact the customer almost always specs SS fasteners

(7)I worked for such industries for over 40 years.

(8)the main reason the car companies don't use SS is cost and less expensive plated steel fasteners are reasonably good for corrosion performance

(9) so like others have said, you can use SS with anti-seize fasteners into mild steel or aluminum with no issues
just don't use SS fasteners that you buy at HomeDepot as structural connections

 

[ez-duzit]

Awful lot of nonsense laid out so far.

Stainless is perfectly safe to use for replacements anywhere ordinary steel hardware was previously used. It is used throughout expensive yachts in salt-air environment. Though I would not replace high grade steel fasteners with stainless of the same size where strength is critical. 316 stainless is the most desirable for corrosion resistance.

Do use anti-seize compound on all stainless-to-stainless threads, Recommend Tef-Gel.

 

[orangeblood]

check out the tolerances and specs for ARP bolts. if your truck is a keeper and you plan to restore it you will dig seeing high quality SS bolts on it. they arent cheap but theyll be good looking overkill that will make you smile when you lift the hood.

ARP - New Website Coming Soon

The world leader in high performance automotive fasteners. New website launching soon.

arp-bolts.com

 

[1984shovelhead]

I have no hesitancy using cheap ss hardware in non critical applications like mounting saddle bags blue loctite good idea on bike applications and gives a bit anti gall function

 

[Steve_P]

Typical 18-8 SST fasteners like you'll buy locally or McMaster have a ~36KSI tensile yield strength. SAE grade 5 is ~92 KSI yield. They are not interchangeable in most applications, at least in any application that is load bearing.

 

[joe_padavano]

Typical 18-8 SST fasteners like you'll buy locally or McMaster have a ~36KSI tensile yield strength. SAE grade 5 is ~92 KSI yield. They are not interchangeable in most applications, at least in any application that is load bearing.

McMaster has plenty of stainless fasteners at 110 KSI and above. 316, 400-series, and even A286 that is 170 KSI. You can get the material certs for them if you want.

 

[jagwinn]

Stainless fasteners are used in food/pharmaceutical manufacture to meet FDA requirements...when doing equipment change overs, we would have new fasteners to replace the rounded heads and galled nuts.

 

[Dan in Pasadena]

Of course it depends where you intend to use it but I have stainless steel fasteners all over my '55 Chevy truck. Anti seize on all of them of course.

 

[PZ 1]

Anti seize is only needed when using power tools. If using hand tools it is not necessary.

 

[rsanter]

Stainless is great to use all over the car.
There are a few base rules you need to follow when using stainless.

Do not put a stainless nut onto a stainless bolt. It will gaul.
Use a regular steel or brass nut.

So not use in high stress or high tension applications unless the bolt is specifically rated for that. It use daily to be that all stainless hardware was low strength, this is no longer the case but you will need to be sure that the specific bolt is rated for the specific application.

Never use stainless anywhere inside an engine to hold anything important.

Galvanic corrosion. As long as you put a small stainless bolt into a large item you do not have an issue. Example, stainless bolts holding exhaust manifold to iron head. No issue.
Using an iron bolt in a stainless head, the bolt will just about dissolve. Hard to explain but it has to do with the ratio/mass of the head verses the mass of the bolt.

Holding brackets, body panels, decor items, clamps.....etc.....perfect application

I use stainless bolts extensively in my cars and I love it. Bolts that would normally give issues after a bunch of years come out with little trouble.

Tip....be sure of the grade of bolts you are getting. Unrated stainless fasteners you can assume will be grade 2 at best. If the MFG does not specify the grade.....well there is not much of one

Bob

 

[ez-duzit]

...
Do not put a stainless nut onto a stainless bolt. It will gaul...

Bull spit.

 

[ez-duzit]

Anti seize is only needed when using power tools. If using hand tools it is not necessary.

Bull spit.