Early Front Springs

[maineSS]

I notice upon looking at my 49 B1 front springs that the eyelet leaf is in 3 parts! It's definitely designed this way- both springs are like this. The eyelet ends are pointed, and the center piece is V'd to receive them. They also have the underside relief on the lower leafs. Any special advantage to this 3-piece leaf? I'm thinking about replacing it with a 1-piece leaf. I'm installing a winch, and am also wondering if I should go to 12 leaves instead of the original 11.

[Clint Dixon]

Keep 'em!

I notice upon looking at my 49 B1 front springs that the eyelet leaf is in 3 parts! It's definitely designed this way- both springs are like this. The eyelet ends are pointed, and the center piece is V'd to receive them. They also have the underside relief on the lower leafs. Any special advantage to this 3-piece leaf? I'm thinking about replacing it with a 1-piece leaf. I'm installing a winch, and am also wondering if I should go to 12 leaves instead of the original 11.

That spring style is what it commonly known as "split main leaves". They have a couple of great advantages - smoother ride and better articulation.

When you get the truck all crossed up with one front wheel stuffed way up in the fender, and the other front wheel at full droop, this is when you can really appreciate split main leaves. They allow the spring pack to "twist", which translates directly into more axle articulation and droop allowing the "downhill" tire to stay in contact with the ground better. Modern vehicles accomplish this articulation without using split main leaves. Instead, they provide for spring twist by using cushioned spring and shackle bushings. The "underside relief" is the grease groove.

Unless your springs are in rally bad shape, I would keep them. With the truck sitting on a level surface without a load in the bed, the front springs main leaf should be horizontal or with with a barely noticeable positive or negative arch.

[maineSS]

The tech at Palmer Spring in Portland (est 1846) said that the three-piece construction was a result of the double wrapped eye- the 3-piece leaf and a continuous leaf being wrapped together at the eye- they apparently couldn't make both leaves continuous that way back in the day. He also passed on a caution- DON"T ever use a hardened center bolt- nothing over Grade 2! The center bolt is made to break first under a heavy impact and let the spring slip. If it doesn't, the next item to break will be a shackle or main leaf, resulting in an immediate loss of vehicle control. The springs are in fairly good shape, so I plan on reusing them. I've heard on winch operation you should block the front springs- unless you have those nifty hydraulic locking struts Clint has for his Good Roads plow setup. They would be useful during A-frame operation also- any modern day substitutes available/

[John Waak]

I replaced my split main leaf setup due to a broken leaf. Since the folks at Eaton did not have that spring in their library, I sent the spring pack to them. They reproduced it perfectly.

[maineSS]

Well, I found that one side of the main leaf is cracked- wish I would have seen that BEFORE getting both eye bushings replaced. I suppose the good news is not finding out while driving down the road. I ordered a new eye leaf with bushings from VPW- hopefully my bottom 3-pc leaf fits round it. If not, I'll need another front spring. John- what did Eaton charge you for your repro?

[maineSS]

Pics # 1 & 2 show what a cracked leaf looks like- anytime you disassemble your springs you should clean up the centerbolt area and inspect it closely. Pic #3 shows the deposits I found between the leaves and also in the axle perch- which is possibly the reason grooved spring leaves stopped being manufactured. I also found an interesting caution on the Eaton Detroit website (www.eatonsprings.com) in the Tech Section regarding greasing leaf springs- DON'T do it on anything manufactured after the mid 50's. The 5160 alloy that replaced the earlier spring steel will fail if exposed to petroleum products (www.eatonsprings.com/atqGreasingSprings.htm). Mike Eaton, who wrote the note, made a classic observation when he said "Looking old, and actually being old can be two very different things". I'm 54, so I can relate!

[John Waak]

Eaton reproduced the split main leaf and charged me $449 for the pair with bushings installed. Shipping was around $30. this was in 2005.
Below is a link to a discussion we had around that time. Good info.
http://powerwagonadvertiser.com/foru...ighlight=eaton

[maineSS]

John- I assume Eaton reproduced the split leaf for you? I spoke with Mike Eaton (company owner), and he said they would likely slot the bottom leaf centerbolt hole to allow the bottom leaf to wrap around the #1 leaf. His take on this was that is was a fabrication problem that was solved by slotting the leaf- which is what I heard from the guy at Palmer Spring in Portland.

[John Waak]

Yes, Eaton reproduced the entire spring pack x2. The number two leaf was split, and the ends wrapped around the number one leaf ends. The rest fof the pack was made up of solid leaves. Interestingly, by 1952, The Dodge part number 1090 570 was for a pair of front springs, one split, the other not. Also by 1952, the lubrication channel was gone.

[maineSS]

Another MacMaster-Carr find- Delrin strip in rolls, 2"x1/32" thick, white or black for leaf spring insert use. The white retails for 80 cents/ft, the black for $1.03/ft. I ordered a 20 ft roll of black, and will cut to fit the leaf and punch out the centerbolt hole. 9 strips will increase spring pack thickness by a little over 1/4" (no delrin in the split leaf). The Delrin allows the spring to stay free even if it rusts, so you don't get "solid suspension syndrome".

[Marius]

MainSS, thanks for the Delrin tip. I have been pondering awhile what to do with my NOS WC-54 Ambulance rear springs. I dont expect them to give much lifetime as they are. Maybe this is the way to go?

[maineSS]

I've cut most of the delrin strips for my front springs- took some pics and worked up a procedure which I'll post soon. If you do this you'll have to make up some new clips, since the spring pack width will grow by 1/32" x the number of inserts. The big advantage is having a working spring ALL the time. One possible problem is having the liners move sideways if they're unrestrained by clips at each end. Since my springs are grooved in the center, and Delrin is thermoplastic, I'll heat a small area of liner over the center groove area, and push it down in to make a dimple to keep the liner in place.

[maineSS]

Here we go on the Delrin-ized front spring adventure. Pic #1 shows the 2" x 1/32" black Delrin strip as received from McMaster-Carr, PN 2638P22 @$1.09 per ft. Pic #2 shows how thick 1/32 (.030) inch is in real life. When you lay out the strip on the leaf, you want to go by the wear mark on the next leaf (pic #3), if you cut according to the inside arc of the bottom leaf, you'll end up too short when the spring extends. (continued...)

[maineSS]

Next, move the leaf out to the cut end, and trace around it with an Xacto blade or something similar (pic #4). Lay the two leaves with the delrin sandwiched between, and repeat the Xacto process- IF you have the grooved type spring, or if all the Delrin strips will be retained by spring clips (pic #5). We will use another strip retention idea for non-grooved springs. A large pair of sharp scissors is best for cutting the strip. When you come to the leafs where the clip bolts ride, extend the Delrin past the spring end as shown in Pic #6- to be continued..

[Cheyenne Dave]

The tech at Palmer Spring in Portland (est 1846) said that the three-piece construction was a result of the double wrapped eye- the 3-piece leaf and a continuous leaf being wrapped together at the eye- they apparently couldn't make both leaves continuous that way back in the day. He also passed on a caution- DON"T ever use a hardened center bolt- nothing over Grade 2! The center bolt is made to break first under a heavy impact and let the spring slip. If it doesn't, the next item to break will be a shackle or main leaf, resulting in an immediate loss of vehicle control. The springs are in fairly good shape, so I plan on reusing them. I've heard on winch operation you should block the front springs- unless you have those nifty hydraulic locking struts Clint has for his Good Roads plow setup. They would be useful during A-frame operation also- any modern day substitutes available/

I would say that the only time blocking the suspension during winch operation is called for is during gin pole operation or when winching a heavy load at a steep downward angle; like pulling a tree up an embankment.

C.D.