4x4 front springs
#1
4x4 front springs
I have an odd question but going to throw it out there I have a 64 f250 4x4 I'm going to be upgrading to a 79 Dana 60 which uses 3 inch wide springs. My truck currently has 2.5 inch wide springs. So the plan is this I want to lift the truck 6 inches using the 99 super duty springs in front I will be making new spring mounts and shackles for the front seeing as though it's almost a bolt in upgrade for the 67-79 f250 I'm looking to find out where the spring mounts on the frame I need to know the distance between the top of the swing shackle bolt hole and the front fixed mount hole . Also if it's possible how the axle centerline fits in there is it directly center of the spring, or longer in one direction or the other ( front or rear)
Any help would be appreciated
Thanks kyle
Any help would be appreciated
Thanks kyle
#5
He's doing an upgrade for his truck using 1979 parts, so he needs measurements from a '79. He's in the right spot, but I only have a half ton, so my coil sprung front end won't help him much. You could give him the numbers he wants by measuring your front axle, Dawg. Maybe take a picture of the spring mounts in front for him?
#7
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Can you get the SD front spring hangers and use them in the 64 mount holes?
Yes the springs can be put on wrong, ie backwards and that will move you axle either fwd or rearward.
If you can get the front hangers on and test hang one spring and roll your axle under it put the spring center pin in the axle spring pad whole and ck axle alignment.
I would of went and measured it for you but I am a long long way from my rigs.
Here is some input from a fellow FTE'er "F350" on the SD front spring swap, hope it helps.
ADVICE #1 "The leaf spring bushings are slightly larger than the original hanger, so grinding the bushing down is a reasonable solution. This only has to be done to the front of the spring. For the rear, I replaced the pivot bushings, and used an off the shelf Toyota poly bushing used in 80's era 4x4's. These bushings had to be modified a little to fit, but worked perfectly.
By taking a small torch to the old bushings, they popped right out, and left a small metal insert in the pivot itself. I was able to leave this in there and not fight it to remove. This can be tough to remove while the pivot is still in the truck.
By taking about 10 thousandths off of the bushing itself, it went in with little trouble. This is almost a perfect fit. Then I lubed up the metal insert, and viola, it is the same width as the spring bushing, and a perfect fit. Front end is done, and everything lines up.
Oh, if the leaf is equipped with a military wrap design, it may have to be either cut or removed to fit the smaller hanger of the highboy. Later 78/9 bolt on hangers are larger and fit the military wrap leaf.
Longer front shackles will have to be made, and the new length should be right at the 5.75" mark. This will provide enough room for the spring to flex and keep the spring from hitting the frame. This has been a problem I have been working out over time. Quality material and thick steel has to be used here. Too small or thin and the shackle will flex.
ADVICE#2
Now we are starting to see why alternative lifts are becoming popular.
With 10 inches, one could assume that you have a desire to clear 44" rubber right?
I only ask because, 10" SD front springs will give you greater than 10 inches of lift over your stock height.
You will have to grind the spring eye bushings a little to fit inside of the 75 spring hangers. A few minutes with a flap wheel and an angle grinder will make short work of this.
You will also have to make longer shackles for the front springs. If you do not jump the truck, or get overly aggressive, you can get away with a shackle that is 5.25 inches. This will clear the frame, and allow a decent amount of pivot. The shackle angle will increase with the use of the longer SD spring, but this angle is good, and contributes to the better ride quality.
At this time, you will probably want to replace the front pivot bushings. I can guarantee that your 30 year old ones are shot.
You will want to be aware that this extended shackle does affect "caster" so caution must be used when making this modification. Too long, and the pinion angle gets wacky, and the truck steers very slow.
You will have to remove the entire leaf that makes up the "military wrap". This is the second leaf in the pack. The diameter will not fit in the stock hanger. I have run with the entire leaf removed, and have cut the wrapped portion out of the pack. Removing the leaf itself allows for more flex. I have yet to encounter a failure, or bend a main leaf after a removal. I am pretty hard on my vehicles.
After this, the spring mounting hardware will have to be addressed. The bushings are a larger diameter, and will require you to drill the hanger to a larger size. You can either drill to 18mm and buy an 18mm bolt for the front, or make the bushing larger to accommodate a 3/4" bolt. Since you are making your own shackles, you can use the stock size upper bolt, and drill the lower to the appropriate size.
Yes the springs can be put on wrong, ie backwards and that will move you axle either fwd or rearward.
If you can get the front hangers on and test hang one spring and roll your axle under it put the spring center pin in the axle spring pad whole and ck axle alignment.
I would of went and measured it for you but I am a long long way from my rigs.
Here is some input from a fellow FTE'er "F350" on the SD front spring swap, hope it helps.
ADVICE #1 "The leaf spring bushings are slightly larger than the original hanger, so grinding the bushing down is a reasonable solution. This only has to be done to the front of the spring. For the rear, I replaced the pivot bushings, and used an off the shelf Toyota poly bushing used in 80's era 4x4's. These bushings had to be modified a little to fit, but worked perfectly.
By taking a small torch to the old bushings, they popped right out, and left a small metal insert in the pivot itself. I was able to leave this in there and not fight it to remove. This can be tough to remove while the pivot is still in the truck.
By taking about 10 thousandths off of the bushing itself, it went in with little trouble. This is almost a perfect fit. Then I lubed up the metal insert, and viola, it is the same width as the spring bushing, and a perfect fit. Front end is done, and everything lines up.
Oh, if the leaf is equipped with a military wrap design, it may have to be either cut or removed to fit the smaller hanger of the highboy. Later 78/9 bolt on hangers are larger and fit the military wrap leaf.
Longer front shackles will have to be made, and the new length should be right at the 5.75" mark. This will provide enough room for the spring to flex and keep the spring from hitting the frame. This has been a problem I have been working out over time. Quality material and thick steel has to be used here. Too small or thin and the shackle will flex.
ADVICE#2
Now we are starting to see why alternative lifts are becoming popular.
With 10 inches, one could assume that you have a desire to clear 44" rubber right?
I only ask because, 10" SD front springs will give you greater than 10 inches of lift over your stock height.
You will have to grind the spring eye bushings a little to fit inside of the 75 spring hangers. A few minutes with a flap wheel and an angle grinder will make short work of this.
You will also have to make longer shackles for the front springs. If you do not jump the truck, or get overly aggressive, you can get away with a shackle that is 5.25 inches. This will clear the frame, and allow a decent amount of pivot. The shackle angle will increase with the use of the longer SD spring, but this angle is good, and contributes to the better ride quality.
At this time, you will probably want to replace the front pivot bushings. I can guarantee that your 30 year old ones are shot.
You will want to be aware that this extended shackle does affect "caster" so caution must be used when making this modification. Too long, and the pinion angle gets wacky, and the truck steers very slow.
You will have to remove the entire leaf that makes up the "military wrap". This is the second leaf in the pack. The diameter will not fit in the stock hanger. I have run with the entire leaf removed, and have cut the wrapped portion out of the pack. Removing the leaf itself allows for more flex. I have yet to encounter a failure, or bend a main leaf after a removal. I am pretty hard on my vehicles.
After this, the spring mounting hardware will have to be addressed. The bushings are a larger diameter, and will require you to drill the hanger to a larger size. You can either drill to 18mm and buy an 18mm bolt for the front, or make the bushing larger to accommodate a 3/4" bolt. Since you are making your own shackles, you can use the stock size upper bolt, and drill the lower to the appropriate size.
#13
Thanks for the info I'm fabbing up custom hangers so I'll allow for the military wrap on the leaf also I know the ad springs set the axle back a couple inches so this is why I was asking for measurements on the frame pivots so I can allow for the longer leaf to set the axle at the same point
#14
I too got 54 1/2" on the frame from hole center to hole center (shackle at rear to front hole of fixed hanger at front of truck)
My axle was dead center at 27 1/4"
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FordOwnerJoey
1987 - 1996 F150 & Larger F-Series Trucks
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06-21-2012 06:18 AM