cracked frame 79 k10

[lax79k10]

I need to fix the frame. Any one that could help me out in how. Or if you're in the Orange County area, if you could recommend a good shop. Thanks.
I have done some reserch I just need another opinion from you guys.


Its the rear right side shock support. 

[winky]

if it was mine i would clean it, weld it, then reinforce it with a plate.

[Mario]

I would spend a lot of time, grinding a groove into one side or both sides.  Set up a situation to bring the bottom flange back together, then put a groove weld into one or both sides of the crack.  Then I would remove the shock and do the same on those smaller cracks.  It seems like your shock seized up, and started a snow ball effect.  If you had full penetration from a groove weld, then you wouldn't need any additional reinforcement.  JMO...  Good luck, Man!   

[bd]

This is true...

I would spend a lot of time, grinding a groove into one side or both sides.  Set up a situation to bring the bottom flange back together, then put a groove weld into one or both sides of the crack.  Then I would remove the shock and do the same on those smaller cracks....  JMO...  Good luck, Man!

This is not true if you want a permanent repair...

...It seems like your shock seized up, and started a snow ball effect.  If you had full penetration from a groove weld, then you wouldn't need any additional reinforcement....

As one repair option...

Frame cracking around the rear frame shock mounts is common on these trucks, because the outboard end of the shock-pins are not supported.  Cracks nearly always initialize around the shock-pin holes from leveraging by the shock-pins and then propagate outward.  In addition, rear spring flex stresses the arch of the frame, concentrating stress in the lower flange - that's why the crack opened downward.   A simple fix when caught early enough.

But, since the crack has migrated through the flange, the frame rail needs to be clamped back into its original position and shape, and then tacked.  Each crack needs to be carefully traced to its ends and 1/8" holes drilled through the frame to stop further crack migration.  Next, v-groove every crack about 2/3 of the way through the frame.  Weld the cracks from both sides for full penetration, then dress the welds down to the frame's original thickness, so the surface is smooth with no pinholes or pits.  Take your time.  A good weld and finish are crucial.

Now for the real fun.  Hammer form a 3/16" mild steel plate to fit inside the frame rail like a glove, so that it conforms to the contours of the rail as closely as possible and overlaps the long crack, front-to-rear, by several inches.  Do your best to eliminate any gaps between the fit of the plate against the rail.  The ends of the plate should not be cut square, but rather scalloped to help disburse stress.  Spray bare metal with weld-through primer then tightly clamp and weld the glove into position.

You should also fabricate a 3/16" thick reinforcement strip that's slightly wider than the flange and about one foot long to fit the outside bottom flange of the frame and weld it into place.  Trim the strip so that the ends are round instead of square.  Avoid a continuous weld bead when installing the lower flange reinforcement - space 2" long beads about 1" apart.

You're almost done.  To prevent recurrence, fabricate a stout 1/4" thick outboard bracket that supports the outer end of the shock-pin and bolt on using grade-8 flanged frame bolts.  The bracket needs to attach such that it holds the upper shock mount rigid without interfering with shock motion as the springs flex and the axle moves.

Now check the opposite frame rail and both front shock mounts and repeat as necessary.  Now, is a great time to inspect the frame around the steering box mounting, as well.

[lax79k10]

THANKSS
BD ON POINT. THANKS A LOT! I'LL POST SOME PICTURES UP

[winky]

This is true...

I would spend a lot of time, grinding a groove into one side or both sides.  Set up a situation to bring the bottom flange back together, then put a groove weld into one or both sides of the crack.  Then I would remove the shock and do the same on those smaller cracks....  JMO...  Good luck, Man!

This is not true if you want a permanent repair...

...It seems like your shock seized up, and started a snow ball effect.  If you had full penetration from a groove weld, then you wouldn't need any additional reinforcement....

As one repair option...

Frame cracking around the rear frame shock mounts is common on these trucks, because the outboard end of the shock-pins are not supported.  Cracks nearly always initialize around the shock-pin holes from leveraging by the shock-pins and then propagate outward.  In addition, rear spring flex stresses the arch of the frame, concentrating stress in the lower flange - that's why the crack opened downward.   A simple fix when caught early enough.

But, since the crack has migrated through the flange, the frame rail needs to be clamped back into its original position and shape, and then tacked.  Each crack needs to be carefully traced to its ends and 1/8" holes drilled through the frame to stop further crack migration.  Next, v-groove every crack about 2/3 of the way through the frame.  Weld the cracks from both sides for full penetration, then dress the welds down to the frame's original thickness, so the surface is smooth with no pinholes or pits.  Take your time.  A good weld and finish are crucial.

Now for the real fun.  Hammer form a 3/16" mild steel plate to fit inside the frame rail like a glove, so that it conforms to the contours of the rail as closely as possible and overlaps the long crack, front-to-rear, by several inches.  Do your best to eliminate any gaps between the fit of the plate against the rail.  The ends of the plate should not be cut square, but rather scalloped to help disburse stress.  Spray bare metal with weld-through primer then tightly clamp and weld the glove into position.

You should also fabricate a 3/16" thick reinforcement strip that's slightly wider than the flange and about one foot long to fit the outside bottom flange of the frame and weld it into place.  Trim the strip so that the ends are round instead of square.  Avoid a continuous weld bead when installing the lower flange reinforcement - space 2" long beads about 1" apart.

You're almost done.  To prevent recurrence, fabricate a stout 1/4" thick outboard bracket that supports the outer end of the shock-pin and bolt on using grade-8 flanged frame bolts.  The bracket needs to attach such that it holds the upper shock mount rigid without interfering with shock motion as the springs flex and the axle moves.

Now check the opposite frame rail and both front shock mounts and repeat as necessary.  Now, is a great time to inspect the frame around the steering box mounting, as well.

^^ thats what i meant bd is just awesome with details and explaining everything to  where it is simple to understand, that's why he is such a great asset to this forum. i should have said something about drilling the holes i guess it was just late and i was in a hurry. this same principle applies to pretty much anything with a crack that you are repairing. Fiberglass, metal, plastic so keep that in mind if your ever repairing cracks in something else.

bd,
Would you recommend drilling some plug holes in the reinforcement plate to weld up to help hold it together or just weld it along the edges?

[bd]

Would you recommend drilling some plug holes in the reinforcement plate to weld up to help hold it together or just weld it along the edges?

That depends on the size of the plate, the conformity of the plate to the frame, and the skill of the welder.  If the plate conforms to the frame exceedingly well and is more than ~6" long, and if the welder is skilled, then I think strategically placed plug welds could benefit the repair.

[bake74]

     Quote from bd "But, since the crack has migrated through the flange, the frame rail needs to be clamped back into its original position and shape,.  This should be your first and primary mission before doing anything else.
     You will more than likely have to at the least loosen all bed mounts and remove shock on that side.  It is very important to get the frame back to as close to stock as possible before making any fixes.
     If you end up taking it to a shop, make sure they explain to you what they will do, if they say just weld it in place, go somewhere else.

[lax79k10]

Sure. Will. I havent got the chance to do weld it. Because of work. Im sure I'll get it done this month.
So.... to i have to remove the leaf springs to get it in place?

[bake74]

Sure. Will. I havent got the chance to do weld it. Because of work. Im sure I'll get it done this month.
So.... to i have to remove the leaf springs to get it in place?

     That is a case by case problem.  My answer, if you can not get it back to it's original shape, then start removing things until you can.  Sometimes the answer is the simplest thing to do.