Suspension fixings, bolts etc

[hot metal]

I am stripping out suspension parts for a general clean up or replacement, wish bones ,springs & so on. Is it ok to use stainless nuts & bolts when reassembling , only I think somebody once told me it`s not recommended .

Thanks ..........

[Belle427]

I've not looked into the science of it but it's said to be a big no no due to the lower tensile strength of the stainless.

[CouncilFerrari]

Stainless steel is quite brittle, which makes it not very suitable for suspension bolts etc.

You'll probably be able to find zinc plated bolts in the right tensile strength from Kays fasteners or similar, on eBay etc.

[phillpot]

General opinion is no stainless for suspension bolts, RT Racing or one of the big TVR Specialists used to do a "bolt kit."


Safety is obviously the main thing but a lot of the suspension bolts are imperial sizes, they'll cost you a fortune in stainless!

[hot metal]

Thanks for the replies, I`ll go with plated I think, there`s a supplier local to me that can supply with the correct items .

[Andy70]

I work with stainless, T304 and marine grade 316 isn't brittle, if it was you couldn't bend it into exhausts, we have tons of stainless nuts and bolts at work, stainless is much stronger than mild steel. All we have is metric though, if you can give me a metric equivalent I could pop you some bolts and nyloc nuts in the post if we have the size that is, our sizes are specific for what we use them for, but you never know, PM me if you are interested that is. Our application is hot air balloons and the safety around that is far greater than any car

[BritishTvr450]

I don’t see the point of using stainless over nickel plated bolts for suspension components.
The most important thing is the bolt size is accurate to the 1/000th or you’ll get rattle or play and fuvk everything up.

I can honestly say the original 20 year old bolts removed from my wishbones when doing a body off had no corrosion on the shanks and entirely intact.
About 8 years ago now me and friends replaced my Diff and re greased the bolts on assembly and that grease was still there and also like new when I removed them for the body off.
Just re use those original bolts as they are probably better than new bolts which I fear are of a lessor quality.

[gamefreaks]

You can buy a full suspension bolt kit from TVR Parts or whatever they are called now.

You need to use the right grade of bolt for suspension parts too. SS use different grades and I don't think there is an 'equivalence'.

A lot of the bolts will be grade 10.9's whereas the B&Q pick 'n mix bins will be grade 4.8 or something.

You can identify the grade and strength of a bolt by marks or numbers on the head.

https://www.dgmfmoldclamps.com/what-are-metric-bol...

[hot metal]

BritishTvr450 said:

I don’t see the point of using stainless over nickel plated bolts for suspension components.
The most important thing is the bolt size is accurate to the 1/000th or you’ll get rattle or play and fuvk everything up.

I can honestly say the original 20 year old bolts removed from my wishbones when doing a body off had no corrosion on the shanks and entirely intact.
About 8 years ago now me and friends replaced my Diff and re greased the bolts on assembly and that grease was still there and also like new when I removed them for the body off.
Just re use those original bolts as they are probably better than new bolts which I fear are of a lessor quality.

I get this, had to cut one off, the others just look scruffy on the heads, shanks look fine . I visited a local supplier today, sorted me out with all new items, nuts, bolts washers, all good. Get home ,they are loose in the bearings, so he will be getting a visit on Monday, no biggie ,not ready to reassemble yet.

I am pretty sure I used stainless on the front, 10 years ago when I replaced the front wishbones ,no major disasters since, hmm ,something to dwell on.

[hot metal]

gamefreaks said:

You can buy a full suspension bolt kit from TVR Parts or whatever they are called now.

You need to use the right grade of bolt for suspension parts too. SS use different grades and I don't think there is an 'equivalence'.

A lot of the bolts will be grade 10.9's whereas the B&Q pick 'n mix bins will be grade 4.8 or something.

You can identify the grade and strength of a bolt by marks or numbers on the head.

https://www.dgmfmoldclamps.com/what-are-metric-bol...

A friend is coming over in the morning to help with a couple of things on the car, he`s an ex Rolls Royce engineer, I`ll pick his brain a little.

[Belle427]

I always use copper grease on suspension bolts, especially the tricky ones to remove. Its amazing how much easier stuff comes apart if needed.
Im fully aware of the implications on torque values but i dont think ive ever broken out the torque wrench for many jobs on a car.

[BritishTvr450]

Belle427 said:

I always use copper grease on suspension bolts, especially the tricky ones to remove. Its amazing how much easier stuff comes apart if needed.
Im fully aware of the implications on torque values but i dont think ive ever broken out the torque wrench for many jobs on a car.

Belle427 Check your emails

[Belle427]

Responded to your email, thanks.

Edited by Belle427 on Saturday 16th November 10:33

[fieryfred]

Stainless is normally used for looks & corrosion resistance i.e. salt water.
They are not suitable for high torque applications. AKA Ape on a 4ft scaffold pole.
In high torque applications you have to replace the bolts.
Nice thick bolt but the only thing holding nut & bolt together is the thread. This stretches under high torque.
You need a fine thread & not a coarse thread for this.
No one sees your suspension bolts so zinc plated 8.8 is cheaper.
No Ape & scaffold pole is needed for your suspension. But bolt heads get mangled over time so just replace.
In your history file that will gain you Brownie points.
You wont be going fast enough to trouble any stainless bolt unless you car is red.