90'K5
1/2 ton status
The D60 under the K5 stripped a hole so I replaced it with a u-bolt. But, I have another D60 sitting in the garage that someone has already tapped - it had 3/4" bolts when I bought it 
CK5
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machined a D60 thread repair Drill Jig. Pics. *UPDATE* REPAIRED. Paging Brent
- Thread starter rdn2blazer
- Start date
moneypit_K5
1/2 ton status
I didn't realize this was such a common issue.
I just looked under mine yesterday, and evidently one of the bolts actually broke about 3/4 of an inch in. Im contemplating how to fix it as I read this thread.
I just looked under mine yesterday, and evidently one of the bolts actually broke about 3/4 of an inch in. Im contemplating how to fix it as I read this thread.
studs are VASTLY superior to bolts IMO.... seems silly to me NOT to run em, $10 in hardware....
pennsylvaniaboy
1/2 ton status
i would agree. one question is tho looking on fastenal's website to get a 5/8-11 helicoil the OD is 7/8-9. im not sure there is that mch material to put a 7/8 hole in there. would it just be better to drill it for a 3/4 tap and then run a 3/4 stud?
blazin_blazer
1/2 ton status
won't going to 3/4'' studs centered where the original bolts were, cause the 3/4'' studs to hit the leaf springs, and not allow enough room between the u-bolt & the larger 3/4'' stud for the leaf spring? seems like the inside of the 3/4'' threaded holes would need to be even w/the inside of the original bolt hole, so the added thickness of the 3/4'' stud does not protrude inwards toward the center of the perch, causing there not to be enough room for the leaf springs to lay flat on the perch between the u bolt and the larger studs, w/o it trying to spread the studs? what am i overlooking here? 
pennsylvaniaboy
1/2 ton status
yeh i havent looked at it. i am at school about 2 hrs from the truck. chances are you will be correct. im just curious if there is room for the 7/8 hole needed for a 5/8 stud
won't going to 3/4'' studs centered where the original bolts were, cause the 3/4'' studs to hit the leaf springs, and not allow enough room between the u-bolt & the larger 3/4'' stud for the leaf spring? seems like the inside of the 3/4'' threaded holes would need to be even w/the inside of the original bolt hole, so the added thickness of the 3/4'' stud does not protrude inwards toward the center of the perch, causing there not to be enough room for the leaf springs to lay flat on the perch between the u bolt and the larger studs, w/o it trying to spread the studs? what am i overlooking here?
Something I will look into before I just go to drilling for sure. Thanks for the Info I over looked.
If you are running lift springs and/or rear springs, probably clear.
Most lift springs and chevy rear springs will be 2.5" where as your factory fronts are 3". Give you and extra .25" per side.
Still seems like its gona be tight concerning the wall thickness of the part where the studs go in.
Most lift springs and chevy rear springs will be 2.5" where as your factory fronts are 3". Give you and extra .25" per side.
Still seems like its gona be tight concerning the wall thickness of the part where the studs go in.
desertrat67
Hawk Driver
As I stated previous, I have threadserts in mine. I will go tomorrow and take a couple pics to show what clearance there is.
Everything looked completely fine when I picked it up and installed it 3 years ago.
As I have stated though, threadserts, not helicoil.
Everything looked completely fine when I picked it up and installed it 3 years ago.
As I have stated though, threadserts, not helicoil.
pennsylvaniaboy
1/2 ton status
desertrat67
Hawk Driver
Similar concept except the threadsert isnt a coil that is threaded into the hole like a helicoil. The threadsert is a solid body that gets threaded in, so it is a stronger application. The helicoil looks like a spring that gets threaded in.
The top piece is a helicoil and the bottom a threadsert. The threadsert will be threaded on the inseide to accomodate the bolt/stud being installed:
As you can see, the threadsert is much sturdier, but also a lot thicker so it will require the removal of more material. This can be a problem in tight confined areas that cant afford to have material lost.
The top piece is a helicoil and the bottom a threadsert. The threadsert will be threaded on the inseide to accomodate the bolt/stud being installed:
As you can see, the threadsert is much sturdier, but also a lot thicker so it will require the removal of more material. This can be a problem in tight confined areas that cant afford to have material lost.
pennsylvaniaboy
1/2 ton status
so these are what i have found from fastenal
http://www.fastenal.com/web/products/detail.ex?sku=0123128&ucst=t
that has a thread depth over an 1"
this one is under 1"
http://www.fastenal.com/web/products/detail.ex?sku=60160&ucst=t
thoughts or comments?
http://www.fastenal.com/web/products/detail.ex?sku=0123128&ucst=t
that has a thread depth over an 1"
this one is under 1"
http://www.fastenal.com/web/products/detail.ex?sku=60160&ucst=t
thoughts or comments?
blazin_blazer
1/2 ton status
aaaahhhh yes, i knew there had to be something i was overlooking or this wouldn't work, i.e....this wouldn't work w/factory 3'' wide springs, but as kert pointed out the lift springs and rear springs are 1/2'' narrower, thus allowing the use of the larger diameter studs.
this being the case, while doing a 1ton swap, is there any reason to go ahead & upgrade to 3/4'' studs to increase the strength before you have trouble, or just run the factory sized threads & studs until they give you trouble then upgrade to the 3/4'' studs?
desertrat67
Hawk Driver
It rained here all day and I didn't feel like taking pics while sitting in a puddle, so you will have to wait until tomorrow.
I'm going with the 3/4 tapped into the housing, Then later if I have a problem I will drill it for a Keensert that is for a 3/4 stud.
I've had the same problem. Bought the 3/4 studs, got ready to drill and tap it out and am a little worried about the thickness of the housing in the outer most part of the front hole. When drilled and tapped for a 3/4 stud I believe that's going to be a really weak area. May just be looking to far into it but just my thoughts. I just hate having it sitting here and not being able to wheel.
Finally got around to doing the repair on my 60 I've needed to do for a while. My drill jig work pretty damn good if I do say so myself . I bolted down one end using a 5/8 bushing to align the holes. The bolted hole has a Helicoil in it already. I still want to repair that hole and drill & Tap it too, but for now I can temporarily bolt the axle in the truck and get it on wheels. The casting surface is not flat at all. So I disc sanded it some what to make it a little better for the block to sit on.
I had to clamp the one end so I came up with this setup using a 1-2-3 block. I also had to shim under the block using a .025 shim under the block on one end and .015 on the other end. It's eyeballed as flat as I think it should be. Good enough for me. First I drilled it with a drill bushing as described in the first post. Then I used a larger bushing and drilled it out bigger, then I used another bushing and reamed it to size for a 3/4-16 fine thread. There is plenty of meat around the hole IMHO, 1/4 inch or more. Also, I tapped 1 1/2 inch deep, and ran a 3/4-16 bottom tap in too so it's got deep threads for sure. I'm not worried about pulling these out. IF I ever do then I will go to the "U" bolt setup some guys are running.
I have 3/4-16 grade 8 heat treated threaded rod so thats what I'm using to bolt the spring plate up with on the inboard side and the U bolt of course on the out board side On to the pics.
. I bolted down one end using a 5/8 bushing to align the holes. The bolted hole has a Helicoil in it already. I still want to repair that hole and drill & Tap it too, but for now I can temporarily bolt the axle in the truck and get it on wheels. The casting surface is not flat at all. So I disc sanded it some what to make it a little better for the block to sit on. I had to clamp the one end so I came up with this setup using a 1-2-3 block. I also had to shim under the block using a .025 shim under the block on one end and .015 on the other end. It's eyeballed as flat as I think it should be. Good enough for me. First I drilled it with a drill bushing as described in the first post. Then I used a larger bushing and drilled it out bigger, then I used another bushing and reamed it to size for a 3/4-16 fine thread. There is plenty of meat around the hole IMHO, 1/4 inch or more. Also, I tapped 1 1/2 inch deep, and ran a 3/4-16 bottom tap in too so it's got deep threads for sure. I'm not worried about pulling these out. IF I ever do then I will go to the "U" bolt setup some guys are running.
I have 3/4-16 grade 8 heat treated threaded rod so thats what I'm using to bolt the spring plate up with on the inboard side and the U bolt of course on the out board side On to the pics.
More pics
I'd be interested as well if the opportunity is there.
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