Rear Suspension Mod's For Big Blue?

[Gary Lewis]

You can count! Amazing! I was saying what I have, if you want from the same angle it will have to wait probably until Thursday. But here are some when I was swapping rear axles.

As you can see, my overload springs are on top and the frame has a pair of angles with rubber pads that come down to sit on the overload leafs when needed I think if you go back and look at the spring chart for both Big Blue and Darth you will probably find Big Blue is way oversprung.

Oh, yours! Ok, now I understand. But, no need for further pics as I can see what you have quite well. And it appears that Big Blue a bigger spring pack than Darth does. But, I'll take some measurements tomorrow and maybe you can check my measurements against Darth's to help me understand if that is really the case.

[Ford F834]

Oh, yours! Ok, now I understand. But, no need for further pics as I can see what you have quite well. And it appears that Big Blue a bigger spring pack than Darth does. But, I'll take some measurements tomorrow and maybe you can check my measurements against Darth's to help me understand if that is really the case.

Gary, mine has an upper overload like Darth. There is a spacerbetween the rest of the spring pack and the upper leaf which I do not see on Darth’s, but mine is 4x4. As mentioned it does take a LOT to squat it to where the extra leaf contacts the stops on the frame, and in my opinion it rides quite nice. Here is another horrible pic but you can see it if you look:

And a couple from google images in case any future reader needs clarification:

 

[Gary Lewis]

Gary, mine has an upper overload like Darth. There is a spacerbetween the rest of the spring pack and the upper leaf which I do not see on Darth’s, but mine is 4x4. As mentioned it does take a LOT to squat it to where the extra leaf contacts the stops on the frame, and in my opinion it rides quite nice. Here is another horrible pic but you can see it if you look:

And a couple from google images in case any future reader needs clarification:

Interesting. Yours doesn't have nearly as much spring as Big Blue has, but then he doesn't have the overload spring on top. And I don't think he has the stops on the frame for the overload either.

I do have the stops from Dad's truck, which have already been powder coated but not installed as there's no overload spring on Dad's either. I've been thinking about not installing them and saving the weight as they are quite heavy. So, if I decided I needed the overload and found the springs and spacers I could, potentially, use those stops.

[Rembrant]

I am zero help with the springs, but that Trickflow diff cover is a nice piece! I was eyeing them up for my 8.8, and they get rave reviews from those who have installed them.

Carry on...I'll stay out of the spring discussion;).

 

[Gary Lewis]

I am zero help with the springs, but that Trickflow diff cover is a nice piece! I was eyeing them up for my 8.8, and they get rave reviews from those who have installed them.

Carry on...I'll stay out of the spring discussion;).

Thanks! That is just one of the many, many things that Vernon had installed on this truck.

[85lebaront2]

Thanks! That is just one of the many, many things that Vernon had installed on this truck.

Here are a couple more pictures, there is a block between the main spring pack and the overload. What it appears to be is a 3 stage spring. 4 of the 5 main leaves are used empty and light loads, either the 5th leaf or the upper overload (I would have to load the bed until one or the other made contact, but I believe the upper was first from towing the 5th wheel) finally the very stiff 5th leaf makes contact with the main pack.

[FuzzFace2]

Here are a couple more pictures, there is a block between the main spring pack and the overload. What it appears to be is a 3 stage spring. 4 of the 5 main leaves are used empty and light loads, either the 5th leaf or the upper overload (I would have to load the bed until one or the other made contact, but I believe the upper was first from towing the 5th wheel) finally the very stiff 5th leaf makes contact with the main pack.

Gary, what are the tires pumped up to?

Max PSI is for Max load I say lower the PSI for a good ride / handling and keep the springs.

Dave ----

[Gary Lewis]

Gary, what are the tires pumped up to?

Max PSI is for Max load I say lower the PSI for a good ride / handling and keep the springs.

Dave ----

Dave - The max pressure on these Load Range E tires is 80 psi, and I'm running them at 40 so I don't want to take them any lower.

Bill - Your pack is similar to Jonathan's with the overload on top. That's a good approach and I might consider that if I were to find the overload spring and block.

As for what springs I have, I'm not sure. I've measured what I have and they don't match up to any in the catalog. Here are the oddities I've found:

• Big Blue's rear GAWR is 5922, which would suggest the springs should be rated for ~2961 lbs.

• His rear spring code is "K", and that means he should have E3TZ 5560-T springs, which were replaced by E7TZ 5560-A's. But neither of those codes show in the catalog

• His rear axle itself is rated at 6250 lbs

• The current spring pack has 4 leafs that are 23/64" thick, 1 that is 5/16" thick, and then the bottom one that is 9/16" thick. The whole stack is 2 5/8" tall and the springs are 3" wide.

• General Spring says that Big Blue should have 3100 lb springs, and theirs have 6+1 leafs and are 3" wide and 2 5/8" tall.

So it would seem that I do have 3100 lb springs on the rear. And while that is just right to load the rear axle up, I don't need to do that very often. So I want to try pulling a couple of leafs out. We'll see what that does.

 

[Ford F834]

Dave - The max pressure on these Load Range E tires is 80 psi, and I'm running them at 40 so I don't want to take them any lower.

Bill - Your pack is similar to Jonathan's with the overload on top. That's a good approach and I might consider that if I were to find the overload spring and block.

As for what springs I have, I'm not sure. I've measured what I have and they don't match up to any in the catalog. Here are the oddities I've found:

• Big Blue's rear GAWR is 5922, which would suggest the springs should be rated for ~2961 lbs.

• His rear spring code is "K", and that means he should have E3TZ 5560-T springs, which were replaced by E7TZ 5560-A's. But neither of those codes show in the catalog

• His rear axle itself is rated at 6250 lbs

• The current spring pack has 4 leafs that are 23/64" thick, 1 that is 5/16" thick, and then the bottom one that is 9/16" thick. The whole stack is 2 5/8" tall and the springs are 3" wide.

• General Spring says that Big Blue should have 3100 lb springs, and theirs have 6+1 leafs and are 3" wide and 2 5/8" tall.

So it would seem that I do have 3100 lb springs on the rear. And while that is just right to load the rear axle up, I don't need to do that very often. So I want to try pulling a couple of leafs out. We'll see what that does.

Gary, I hope that works. I think it will take stiffness out of the ride. If you like the result, then consider going with the F350 set up and the extra spring on top. I think the only time mine contacted was when hauling gravel. It did squat easier than my old brown ‘81 F250 with overload springs, and that was reflected in the ride quality. That F250 was a rough riding son of a gun with that extra spring pack. The extra upper spring on the F350 is plenty. I once had the guy at the quarry load me up with crusher fines that were still fairly wet after a rain. As he tilted his loader bucket the whole scoop plopped out instead of gradually pouring in as intended. The truck had the full 8 foot bed filled to the bed rails and a peak in the middle that was higher than the cab 😬. And yeah, these were wet crusher fines that were fine enough to cake together. The springs didn’t look bad at all, it was the tires that I was worried about. They were flattened out pretty badly, but I only had a couple miles to go and I kept it under 20 mph.

[Gary Lewis]

Gary, I hope that works. I think it will take stiffness out of the ride. If you like the result, then consider going with the F350 set up and the extra spring on top. I think the only time mine contacted was when hauling gravel. It did squat easier than my old brown ‘81 F250 with overload springs, and that was reflected in the ride quality. That F250 was a rough riding son of a gun with that extra spring pack. The extra upper spring on the F350 is plenty. I once had the guy at the quarry load me up with crusher fines that were still fairly wet after a rain. As he tilted his loader bucket the whole scoop plopped out instead of gradually pouring in as intended. The truck had the full 8 foot bed filled to the bed rails and a peak in the middle that was higher than the cab 😬. And yeah, these were wet crusher fines that were fine enough to cake together. The springs didn’t look bad at all, it was the tires that I was worried about. They were flattened out pretty badly, but I only had a couple miles to go and I kept it under 20 mph.

I would like to find the overload setup for Big Blue as that should be just the right combo.

But your story reminded me of much the same experience. Back in probably '73 we had a winter storm coming into Wichita, so I took my '72 F250 to the quarry to get sand. It was cold enough that the sand had frozen together, and when it finally let loose the whole scoop dropped into the bed. It wasn't as much as you got, but it was a lot and the suspension was well into the overloads.

This was in the days of 16" split rims with skinny tires. I could twist the steering wheel back and forth and the sidewalls would take all the flex. In other words, the truck would turn but the tire patches didn't, and we kept going down the road straight for a bit.