The Stovebolt Site Forums The Shop Area Driveline Replacing the front leaf springs

How do you know when the front leaf springs need to be replaced? Mine on my 53 chevy 3600 are flat.They look shot! But how do I know?

Thanks in advance.
Elmo.

The eyes where the shackle bolts go may have worn through the bushings. If so they’re toast. If not bushings can be replaced and springs re-arched. But it may be easier to just replace them.

If they are original they probably need replacing

Elmo - A couple of other things to look for when you inspect your springs:

Truck sagging/leaning to one side (possibly worn shackles/bushings, but also caused by sagging springs)

Cracked individual spring leafs (even one is enough to consider replacement)

Gouging of leaf springs into the adjacent leaf (metal to metal contact wearing a groove where the smaller leaf end meets the longer leaf)

If you do replace them, be sure to do them in sets (both front, both back or all around). Replacing only one side will lead to some less than fun driving experiences.

Elmo, the leaves on AD trucks lay nearly flat even when new. How does the truck handle. Do you have new radial tires and good, straight wheels? New shocks?

If the front end doesn't bounce all over the place at the slightest uneven road surface, the springs are probably ok.

I'll find a photo of mine or take some pictures tomorrow if you want. I just hauled a load of firewood on an 87 mile round trip on secondary roads and interstate. Truck handles great .

.

Thank you everyone for your replies and pictures, to my question.
As I suspected, mine need to be replaced.

Personally, I like my springs on the aged side of the spectrum as long they aren't clattering over bumps in the road.
I refer to them as being 'broken in'. They tend to make for a smoother ride in my seat of the pants opinion.
New and well lubricated spring pins and bushings are a must have, as well as tight straps which keep the leaf springs contained and aligned.

I replaced the leaf springs today. I Notice under my leaf springs I didn't have the wedge on either side. doesn't the 1953 Chevrolet 3600's have them? They do on the 3100's according to the LMC Youtube video.

Elmo

Your 1953 3600 should have caster shims according to the parts manual. But if the caster angle checks out OK, then they wouldn't be needed. I suspect they will be needed. Your alignment shop can tell you, but they probably won't have any on hand.

Caster shims are easy to find online and at off-road Jeep & truck stores. The may be too long and/or too wide, but a hack saw can fix that.

If it had none to begin with, just drive it.

Where can you buy them at?

Amazon has a collection of leaf spring shims. Some aluminum, which I wouldn't use myself.

Post on Parts Wanted for caster shims for a 3600. There is no better choice than original caster shims. Aftermarket shims will not likely engage the axle properly and will wiggle out of place eventually.

Well, I replaced the leaf springs shackles and front shocks. The old nuts on the U-bolts were a son of a gun to remove. I had to use a 1/2 inch ratchet with a 3 foot cheater bar attached. Three hours later with a lot of wrenching they came off. I order new u bolts to find out they weren't the correct thickness or width. So I went to our local Bumper to Bumper shop and had two new made to the correct specs. The new parts went in easy as pie. I even installed the 4 degree caster shims that were not under the springs when I took it apart.

I dislocated my shoulder last weekend. So my cruise in my truck will have to wait. Of course I screwed up my right shoulder and can't shift the tranny with that arm yet.
I'll get back to you all when I get better. Hopefully I will tell you that it drives straight down the road.

Elmo

did they engage the axle proper with shims installed?

Yes, but I had to make a small modification on the shims. They are not original. I looked in all my parts magazines and none of them had the shims available in them. So I had to install a small screw in the shim where the bump is supposed to be. That bump locates it onto the axle. There is a small hole behind where the leaf springs bolts head goes through and then locates in the straight axle. It worked perfectly. Now it won't wiggle out.
I hope this made sense
Elmo

I wish I knew how to post pics. But I don't.
Sorry

Yeah, Id like to see a pic of that !

Unfortunately, I put it all back together last night. I cannot wait to drive it down the road.

Elmo

I found my truck manual and noticed it said, The caster degree for my 3600 3/4 ton truck should be 2 degrees. So, I ordered them. Im not even gonna drive it. That was a waste of time putting those 4 degree shims in. I also got center pins for the leaf springs. So the shim will be one with the leafs. And they won't wiggle out from under them.

Lesson of the day, don't assume you know what you are doing! Check your manual first.

Elmo

Just to confirm that you have seen the string related to this topic that suggests that the optimum angle is actually closer to 2 1/2 and could be as much as 3. The problem with the 4 degree shims will be harder steering at low speeds.

Yes, I did see that. I've got the 2 degree shims on order. They have to be better than none. Which is what I started out with. And I can't find 3 degree shims anywhere.

My 59 came with a one degree shim. I guess one could add a 2 degree.

Ok Ok, I cancelled my order for 2 degree shims and have 2.5 degree shims coming.

How do you know what angle the shims are? Is it stamped on it somewhere?

I have no idea what are on my truck but I have to assume they've been on it since new. Truck drives and steer perfectly at all speeds , including 55-65.

What angle shim did the factory install?

Otto Skorzeny

My truck is a 1953 Chevrolet 3600 3/4 ton . It was supposed to have 2 degree caster shims installed. If your truck drives and steers perfectly. You don't have any issues on the wandering issue. I do!!

Check your truck manual, It will tell you what you need. The shims are stamped what degree they are. Again, If there aren't any issue with your steering. I wouldn't worry about it.

No, Elmo, I have no intention of doing anything to the springs. I just wanted to know for my own edification.

Total understand. Sorry.

No need to be sorry. I'm a firm believer in not going around looking for stuff to "fix" if it's already working. I just like to know as much as possible so when the time comes I can make the proper repair.

I agree with you 100 percent!!

Hey there WI Cruiser. I bought a pair of caster shims 2.5 degrees. and I had my 4 degree machined down to 3 degrees. So I am ready to find out which works better. I'm going to put them in tomorrow night and see how the truck runs down the road. It's gotta be better than white knuckling driving it. It sucks driving a drunk Goat!!

Driving a drunk goat. That's a good one.