Ford part numbers are divided in to 3 sections – A 4-digit Prefix, the Basic Part Number andthen a Suffix The 4-digit Prefix breaks down like this – First Digit: Decade – C5ZZ5560D A = 1940’s, B = 1950’s, C = 1960’s, D = 1970’s, E = 1980’s, F = 1990’s, etc. Second Digit: Year […]
Manufacturing Springs - Articles, Videos, and Physics
To properly manufacture springs, you need to match blacksmithing and physics to a vehicle's specific requirements. There is no such thing as 'one-size-fits-all' in suspension engineering.
Lucky for you, we do it all! Learn more about the process in the articles and videos listed below. Have your own question? Ask us today!
Three Types of Leaf Spring
There are three types of leaf springs. Multi-Leaf Springs Multi-leaf springs are made up from heat treated strips of SAE 5160 Steel, in diminishing lengths, formed to a predetermined arch and held together by a bolt to the center. Mono-Leaf Springs Mono-leaf springs are a single heat treated plate of steel whose thickness is uniformly […]
Calculating Spring Rate
Mike Eaton explains how to find your coils spring rate using a simple equation. This process is useful for those seeking to cut their coil springs, as it shows how cutting coils lead to a stiffer ride. (Hint: ordering new coils with custom specs, and you can preserve or even enhance your ride quality and […]
Leaf Spring Ends And Hysteresis
Which leaf spring end-type is best for trucks, and which end-type gives you the smoothest riding springs? There are three basic types: square, diamond point, and rolled. Square Ends Square, or constant thickness ends, are great for trucks, terrible for cars. It puts a concentration of all the pressure at the end of the leaf, […]
All About Our Spring Steel
Springs can’t be made from just any metal. They need to be made from a steel that has a high yield strength, helping it retain it’s original shape after significant pressure is applied. Surprise, surprise: a spring’s steel needs to be able to bounce back. So what type of steel would be perfect for building springs? […]
How Leaf Springs Are Made
We manufacture leaf springs all year long, and one thing everybody who comes to the shop wants to see is how it’s made. Well, not everyone can make it out to Michigan and Trumbull in Detroit, so we made this six minute video with Jeff Ford of Autorestomod to give you a special look into […]
Never Weld Springs (Do This Instead)
Why shouldn’t you heat up springs? For safety’s sake.
Spring Rate Vs Load Rate
Understanding spring terms will make your suspension build a thousand times easier.
Mono-Leaf Springs
Are mono-leaf springs dangerous? Only if you buy from the wrong people.
Rearching C1 Corvette Springs
I have Corvette leaf springs with grooves. Can we restore them or should I have new ones fabricated?
Springs & Air Bags
Mike, I have a 1968 Camaro Hardtop that I want to lower 2 Inches in the rear. I have headers and dual exhaust, which sometimes scrape on the driveway, so I want to install air bags to lift it as required. My question is, how does this affect the suspension and spring rate? Can I […]
Heavy Duty Coils
Q -Kind of a follow up question to last week’s email question, Ken from Lancaster, CA wrote and said he went to the local auto parts store and told them he wanted to raise his car about an Inch or two and they sold him heavy duty coil springs. But when he installed them the […]
Leaf Spring Clips III
Mike, I am curious if there is a part that the leaf spring clamps play with regards to the function of a rear leaf spring? Is there a difference for instance on how many clamps are placed on a five leaf set up as opposed to a four leaf, and are the locations of the […]
Leaf Liners, Powder Coat & U-Bolt Torque
Mike, I wish I had read your tech page about two months ago. I just had my leaf springs powder coated and I’ve re-assembled the front springs with poly liners between the leafs. Am I correct in assuming that your advice for nothing to be between the springs also applies to these poly liners? If […]
Leaf Spring Rust
Mike, I purchased some custom lowered springs from you this past summer. They came unpainted and I put them on my car without painting them. Over the weekend I was putting her away for the winter and noticed that the springs were rusting. Should I be concerned about the rust and if so, what should […]
Leaf Finish
Mike, Please can you inform what’s the best/correct finish for both the visible and invisible (IN THE STACK) parts of leaf springs? A couple of people I know insist on painting them totally including all in between the leafs, the normal for them bondaprimer / undercoat / enamel topcoat layers. (They do have to externally […]
Mono Leaf Springs
Mike, I want to install a set of mono leaf springs on my 1953 Ford f-100. I have a 383 Mopar with a 727 torque flight tranny. Will mono leafs support this unit safely? My friend has them on his with basically the same set up. His springs are straight out with no upward curve. […]
Leaf Liners’ Effect on Spring Rate
Hi Mike, I just read your comment about Delrin inserts and it raised three more related questions I don’t believe I have ever seen answered. The first is, does using a full length insert change the thickness of the spring pack? Secondly, what effect do full length inserts have on spring rate? Finally, in general […]
Monoleaf Mistake
Mike, I bought monoleafs for my truck 8 years ago, not knowing the down side of using them. They sat around for 4 years before I put them on. They sit too low for my taste. To make matters worse, I was sold rear monos with a 6″ drop instead of 4″. Now they are […]
Reducing Inter-Leaf Friction: Leaf Lubricant or Leaf Liners & Tip Inserts?
Mike, I am overhauling a set of springs from a ’64 F250 that are in great shape. I’m getting a list together of hardware to order from you folks. I have read all your tips about coating/painting springs and not using grease between the leafs. My question is that I have heard some people recommend […]
When Do I Install Coil Springs On A Hot Rod? What Do I Do Until Then?
Mike, I recently purchased a 1934 Ford 3 window coupe replica. To make a really long story short its an older kit that just never got put together, but in an excellent condition. My first order of business is to get a rolling chassis. The build book that was provided by the manufacturer calls out […]
Shock And Springs Fight Each Other In A ’64 Straight Axle Vette
Howdy, I have a 64 vette, with a Strange Ford 9”. Yes, it’s a 64 straight axle car. Former drag car. It’s set up like a 62 for the leaf springs. I have 4 leaf springs on there now, which are for a 62, which I purchased from a local vette resto shop. They have […]
Hudson Street Rod
Hello Mike , I am asking for help with a problem I am having on a 1930 Hudson Street Rod. I mounted a Ford Mustang rearend on the original springs, and the springs flatten out with the weight of the car, no arch. With the spring flat the rear shackle hits the fender and wont […]
Monoleaf Springs
Can mono-leaf springs be dangerous?
Grease Between Leaves
Q – Mike: I really enjoyed the opportunity to talk with you during the Silver Springs car show this past weekend. I have also looked at several of your articles on your web site and found them to be very interesting and informative. I also appreciate the T-shirt offer regarding the a discussion we had […]
How Much And When Do Coil Springs Settle? (Also, How To Choose The Right Mustang II Springs)
How much can one expect the springs to settle after installation?
Greasing Leaf Springs
Mike, What effect does grease between the leaves of a pre-50 spring have please? Besides stopping them squeaking. Kind Regards, Mike Mike, If the springs are really pre-1950’s, the grease will help them slide against each other easier and help stop the squeaking. This means springs from the pre-1950’s, not a vehicle from pre-1950’s. Since […]
Which Mustang II Front End Springs Should I Use?
The front springs on my street rod are sagging after installing a big block. How should I go about finding the right replacement springs?
Axle Wrap Cause And Fix
Fixing and understanding axle wrap
How Effective Wheel Weight Can Change What Springs You Need
Dear Mike, We met in Richmond, VA at the NSRA show last August. My car is a 1937 Packard convertible with Fat Man suspension and Mustang II coil springs. The springs had sagged to the point that the lower A-arms were not level but were going up toward each wheel. It had been suggested by […]