One Ton swap

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86chev

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I stumbled across a D60/14BFF combo near where i go to school. Set came out of a early 90's one ton single rear wheel crew cab, 4:10s. Axles are still attached to the frame, my question is if i go about buying the set, what will i all need to be able to swap into a K20? my plan was getting the D60, D60 steering arm, spring pads for on top of leaf springs, 14BFF and the new 56" rear springs. the truck it would go into has a D44, 14BFF, a 4" suspension lift, 52" rear springs and 4" blocks :lazer:. The plan was to swap the one tons in and possibly do a shackle flip with the 56" springs. I see a lot of shackle flips advertised for 1/2 and 3/4s only? would this setup still be an option? :help: thanks everyone
 

heavyleft

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I stumbled across a D60/14BFF combo near where i go to school. Set came out of a early 90's one ton single rear wheel crew cab, 4:10s. Axles are still attached to the frame, my question is if i go about buying the set, what will i all need to be able to swap into a K20? my plan was getting the D60, D60 steering arm, spring pads for on top of leaf springs, 14BFF and the new 56" rear springs. the truck it would go into has a D44, 14BFF, a 4" suspension lift, 52" rear springs and 4" blocks :lazer:. The plan was to swap the one tons in and possibly do a shackle flip with the 56" springs. I see a lot of shackle flips advertised for 1/2 and 3/4s only? would this setup still be an option? :help: thanks everyone

I believe the K20 is the same frame as the K10 (same years). The shackle flip is very do-able. You will néed the 56" springs (as you stated), ORD or DIY4X shackle flip. For four inches of lift I would go with a 4" to 5" shackle (just a good guess-timation). The size of the shackle will vary based on if you keep the overload spring in.

You will also need the appropriate drop pit man arm or knuckle spacer for your steering or go cross over....highly recommend. There is no exact science for getting the appropriate lift when doing a shackle flip. Be aware, going 56" springs will put your axle to the rear a couple of inches due to the location of the spring pack center pin.

In my rig, I used ORD shackle flip, 56" spring plus overload spring from a one ton truck, 5.5" shackles from DIY4X, and a ez-inch from DIY4X and I netted about 6-7" of lift in the rear.

I'm sure I'm missing some other items I'm sure others will chime in with.
 

bucket

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Putting 56's in place of 52's won't change the location of the axle, unless you install the springs backwards. The extra 4 inches of the 56 inch springs is all at the rear.

The one ton rear axle will have a narrower spring perch spacing. Since the frame is available, use the one ton rear spring hangers on the K20 frame. You would also need to use the K30's inboard shock mounts.
 

86chev

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Putting 56's in place of 52's won't change the location of the axle, unless you install the springs backwards. The extra 4 inches of the 56 inch springs is all at the rear.

The one ton rear axle will have a narrower spring perch spacing. Since the frame is available, use the one ton rear spring hangers on the K20 frame. You would also need to use the K30's inboard shock mounts.

It will still have a narrower spring perch even though they are both 14BFF? If i do a shackle flip would i need to get the kit for a K30 then? since both 14 bolts are 4:10s would i save myself some hassle by just using the one currently in the K20 with the 56" springs?
 

bucket

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It will still have a narrower spring perch even though they are both 14BFF? If i do a shackle flip would i need to get the kit for a K30 then? since both 14 bolts are 4:10s would i save myself some hassle by just using the one currently in the K20 with the 56" springs?

Oh, yes of course, if the ratio is the same just reuse your stock axle. I thought you were switching ratios too.

And yes, the one ton trucks have narrower perch spacing, the difference comes from the spring hangers. The shocks mount inboard of the rails since the springs are so close to the frame.
 

towjoe

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don't forget to get the top mounting plates for the front axle. They are different for a dana 60
 

86chev

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don't forget to get the top mounting plates for the front axle. They are different for a dana 60

For on top of the leaf springs you mean?
 

HotRodPC

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don't forget to get the top mounting plates for the front axle. They are different for a dana 60

And very expensive if you can find them. For sure, Be sure to get those top plates without doubt !!!
 

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