Leaf spring drilling

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Jul 9, 2013
Hey guys.

Simple question.

Have any of you changed the location of the center bolt hole in a set of leaf springs? (drilled a new hole further forward)
I'm wondering if this would make the leaf more likely to crack.

I'm messing around with a project for my son's first ride.

Truck is a 71 Fargo 1/2 ton long box (same as a dodge for our American friends)

Truck has no engine right now. I'm going to use the axles off of it on my 37 Fargo rod project (more info to follow)

The reason I want to move it forward a bit, is that I'm going to install a 413 and 727 from a 72 winnebago into it. The wheel base on the winni is 2 inches shorter(yes shorter) than the regular cab pickup. The wheel openings have lots of room, so I figured it would be a cheap way to use the driveshaft from the winni too.

I could probably move the motor and trans back that much too. The trans is cable shift so linkage isn't an issue.

Love this site [P
Although I cannot answer your question on it weakening the springs,to be honest I would just shorten the drive shaft myself as I do for almost all my projects.
I have redrilled a few springs (long ago) never had any problems with cracking.

If you think about it -- if the hole is only a few inches away it will be supported by the u-bolts anyway. Another consideration is that some springs are drilled near the ends and have brackets riveted on and they don't seem prone to cracking
No, you will be fine, but you are going to chew up some drill bits, spring steel is a bear to drill through. I went through quite a few 5/16 bits when I drilled my spring for those teflon buttons you put in the ends.

Those extra holes won't amount to anything significant structurally.

Moving the spring perch center will change the wheelbase, are you planning on running a stock bed?[S If so, it will put the wheels in a different place in the wheel wells, and might look goofy. Why not just get a driveshaft made the correct length? Probably be as cheap or cheaper than all those drill bits and maybe even drill motors you'll need to drill the springs.....

If you don't want to mess with a new driveshaft, willej's idea sounds better, just drill the mounting pads instead of the springs. The center bolt is just a locator anyways to keep the axle from moving on the spring.
A masonry bit will drill spring steel, had to do it on a tailwheel spring for an airplane build. Use lots of coolant to keep the bit from overheating, you'll be amazed how well it works. DR was on the right track, they are carbide cutting edges.

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