Error in spring chart?

[MikeG]

Think I found what may be an error in the spring chart, here:

https://www.therangerstation.com/tech/ford-ranger-explorer-bronco-rear-leaf-spring-specs/

Anyway, years ago I replaced the stock springs in my B4000 with a frankensteined set of various junk. But, I still have the original parts. Out of curiosity, I measured the Explorer parts (not all of which are on the truck) and came up with a pack thickness of 1 and 7/8", which perfectly matches the 1250lb (first entry in the Explorer spring table). So far so good. I don't remember how much arch they had, but it was less than what came off the truck, and 4-5 inches sounds about right, and that first entry shows the least amount of arch of any of them.

My truck is a 97 B4000, 2wd, auto, and had a towing package. So, most likely guess was one of the heavier entries in the Ranger chart. Mind you, the B-series could have had different springs than Rangers, but odds are against it. Unfortunately, the Ranger chart doesn't have the door codes so I had to start measuring things. That's where it doesn't line up.

My original b-series springs have exactly 6" of arch, measuring from the centerline of the eye bolts to the spring where the centerbolt goes through it, and none of the other Ranger springs are supposed to have near that much arch. But the rest of it doesn't quite match. The main leaf is 0.325" or so (I scraped off the rust as best I could with a green scotch-brite pad to get to bare metal), the second leaf is about 0.280" or so, maybe 0.285," the third is exactly the same as the first, and the overload is 0.585" (exactly the same as the Explorer overload).

Granted these are truck springs not racing pistons, so there is surely some tolerance, but something is amiss. Several of the charts have "558" for the overload, and I think that the last two digits are probably transposed.

The first chart shows two leaves at 0.307," but I'm thinking the entry in the chart below it of ".323" is probably what should be in the first chart. .291" is probably close enough to .281 to be correct.

thoughts? Anybody actually measured leaf thicknesses in various rangers? Anyone know which ranger entry corresponds to what door spring codes?

By the way, I have seen this exact chart several other places on the 'net, including a Mazda version that seems to have the same errors, so I'm thinking it just got copied around. Who knows where it came from originally.

In the end, none of this matters much, but I thought it was curious.

 

[don4331]

Now you have me going

The Explorer pack should be a hair under 1-11/16" by adding up the individual components. So, either there is some serious lack on tolerance control, the leaves are not tight together, there has been some creative assembling of components, or there is a paint thickness, which doesn't count to the steel thickness, but adds up in the pack thickness or all of the above.
Note: That would be 3X thicker than a heavy paint job should be - paint usually runs .002 to .007

Out of curiosity, what code do you have for rear springs, and what is rear axle rating?

 

[MikeG]

I think the Explorer spring pack thickness number is counting the two pads between the first and second, and second and third leaves. I counted that in the total when I put the calipers on the spring pack.

My B4000 has a spring code of HE. I'll chase down the rear axle rating in a bit.

 

[MikeG]

Front 2625 Rear 2750.

Ext cab, 4.0L OHV, 355 rear end (towing package), 5r55e auto trans.

 

[don4331]

2625/2750 are both max.

Interestingly my B4000, has B K, for 2710/2600, 4.10 gears, 5r55e auto trans (it is a '07 4x4).

 

[MikeG]

Yeah. Think that the 2wd trucks actually had a higher weight rating than the 4wd trucks.