Disk Brake conversion mistake?

[SCOTI]

Originally Posted by legotech7

Yes 73 to 87, but perhaps the 71 to 72 with disk brakes would work better?

67-72's routed the brake lines along the x-member. 73-87's run the lines through the frame in front of the upper a-arm then across the front splash apron.

My bet is the hose needs to be slightly longer to reach the front area (73-87's) vs. the rear area (67-72's). Get the brake hose for the routing path you used.

[Tx Firefighter]

Originally Posted by legotech7

Already checked the travel with the longer lines, ( up and down, side to side ) and everything looks good.The reason for the bolts going going down is because I read some where here on the forum from who was an airplane mechanic and when he was in school he learned to put all the bolts facing down and nuts with lock washers facing up in case one or more of the nuts should come loose ( with vibration and such ) at least a bolt would still be in its place instead of completely loosing the attachment. I'm not sure if that would work with the upper ball joint, since if all the nuts should come out than with the downward travel I guess the spindle would detach it self from the ball joint.But I find that highly unlikely it would happen. Besides I also used a loctite thread locker on all the bolts and nuts in this particular project, I think I should be good. Its only my weekend beater, can't wait to get it on the road.

Thanks for your suggestions and concerns, I do appreciate it.....

I am an airplane mechanic. I've got the licenses in my wallet. Yes, ordinarily the bolts should face downward like you have them, but in special cases, they do not. This is a special case. Chevy Mike told you correctly. The upper ball joint hardware should be installed with bolt heads down, nut up. It protects the rubber boots from abrasion damage. There's plenty of situations on airplanes where special circumstances dictate that hardware is installed contrary to normal methods too.

[legotech7]

Thanks for the correction, but their in there for now the way they are. First chance I'll switch them around....

[legotech7]

Ok folks, almost done with my bag set up, thanks to all here.. But I have some questions if I may, concerning wheel and tire size, Again I've searched the threads, and as usual am a bit confused as to what I need. Right now I have 15x8 Vintique smoothies with 255/70/15 tires on them. Do you think this would be ok to run on my bagged beast for now? Would they maybe be to tall?. What would the experts here recommend for my bagged set up. I would like to go as low as possible, mostly when the truck is parked. I'm not exactly sure what my optimal ride height is going to be yet, but I need to know what tire size would be best......

Thanks all..........

[SCOTI]

Originally Posted by legotech7

Ok folks, almost done with my bag set up, thanks to all here.. But I have some questions if I may, concerning wheel and tire size, Again I've searched the threads, and as usual am a bit confused as to what I need. Right now I have 15x8 Vintique smoothies with 255/70/15 tires on them. Do you think this would be ok to run on my bagged beast for now? Would they maybe be to tall?. What would the experts here recommend for my bagged set up. I would like to go as low as possible, mostly when the truck is parked. I'm not exactly sure what my optimal ride height is going to be yet, but I need to know what tire size would be best......

Thanks all..........

255-70-15 = 29" tall. Fine for a bagged truck in the rear; a little tall for the front especially w/stock inner wheel wells. 27-28" up front allows lower ride heights & clearance.

If keeping the 8" wheels all around, a 255/60 is 27" & better suited for the front position on a bagged/dropped truck w/stock inner wheel wells.

[legotech7]

SCOTI, I was just searching a bit for some info, and came across one of your post's where another member had a problem with hie front wheels hitting his lower A arm. He had 15'' wheels and your suggestion to him was to trim the arm. Although he had lowered springs on his, as I have bags. Do you think I will have the same problem and might have to trim my arms as well? I thought I was just about done with this truck. I sure hate to have to take everything apart to do this a second time... Your thoughts?

[chevy_mike]

With 2 1/2" dropped spindles, depending on the offset of the wheel, you might run into clearance issues. This is why I went with 2" dropped spindles. Here's a pic with 15x8, 4.5" BS (IIRC) GM wheels with 2" dropped spindles. Close but enough clearance.



As for tire size, I ran 235/70-15 on my 65 truck and I liked it but I wasn't bagged (3" drop). Rear are 255/70-15.

[legotech7]

If you look on post # 20 of this same thread, I mounted the wheel when I got the clearance issue with the caliper done. If you notice the bottom of the wheel with LCA, it cleared but may not be enough when I lay the front to its full travel. Id like to figure out what tire size I'm going to use first mount them on the wheels and try it all out before I think I need to trim the arms. Then If I got a, I got a..... Still I wanted to go with the white wall look for my truck. I love that old school look, so the tire size's are still open...

Thanks........

[chevy_mike]

Opps.... missed that. You have tons of clearance from what I see, way more then I do.

[SCOTI]

Originally Posted by legotech7

If you look on post # 20 of this same thread, I mounted the wheel when I got the clearance issue with the caliper done. If you notice the bottom of the wheel with LCA, it cleared but may not be enough when I lay the front to its full travel. Id like to figure out what tire size I'm going to use first mount them on the wheels and try it all out before I think I need to trim the arms. Then If I got a, I got a..... Still I wanted to go with the white wall look for my truck. I love that old school look, so the tire size's are still open...

Thanks........

The thing about wheel clearance is if they clear (don't rub the a-arms) @ ride height, they'll clear when dumped.

It is common to require some trimming on lower a-arms. Usually it is because of back-spacing and/or 3" spindles which really bring the lip of the rim close to the lower BJ position. It's a simple fix & doesn't require disassembly if done carefully.

[legotech7]

Thank you guys. Will take heath, and proceed as necessary...... To be continued.....

[legotech7]

Well quick up date on the disk conversion. Things are going a little slow, I decided to bleed the system, one man style and discovered a leak on the rear right 1/4'' line than connects to the rubber hose. A small pin hole type of leak. It never ends.......Well I need to replace that line, but its one continuous brake line all the way to the proportioning valve. With its curves and turns it measures 172''...Does that sound right? Can I get a replacement line that long? Or can I just use a union and splice together? The rest of the line is in good shape. Any suggestions on replacing that line? And as long as I'm here asking, I also noticed that the center support where The drive shaft goes through has some sort of support up towards the top of that through hole if you will. I'm thinking I'm going to need to cut or grind that piece out so I can have more wiggle room for that shaft when I lay the truck. Did any of you run in to what might be a problem? I saw that CPP has a support that didn't have that small piece in the center,specifically for lowered trucks. Here's a pic of what I'm talking about.....This is on my truck...I know I'm asking a lot of questions, but like I mentioned earlier in the thread this is all new to me, but thanks to all of you here I learned quite a bit... Thanks a bunch....

[Tx Firefighter]

That center bracket is for a carrier bearing that's used on a two piece driveshaft. If you're running a 1 piece shaft, that will need to go.

The rear brake line should have a union inside of the right frame rail underneath the cab area. You can unscrew it there and replace just the rear section. It's well less than 170".

[legotech7]

Thanks Tx Firefighter , I didn't see a union, but I'll look again, its been a trying day today, I might have missed it. Would it be a problem if I just spliced a another union near where the hole leak is? That would make thinks a whole lot easier......

[Tx Firefighter]

It should be there unless some previous owner has completely replaced the lines and did it all with one solid piece. I'd bet it's there though.

You can absolutely use a union if you need to. Just make sure its a proper one with double flares on the lines. None of that compression fitting stuff on a brake line.

[legotech7]

Thanks man, I'll look into it further. Cant wait to get this all done. I'd like to drive it a bit before the summer is over........

[legotech7]

Just a little update on all I'm doing, Started a little late today, and had to stop early, it is 95 degrees in my neck of the woods, and the garage is about 101..... Anyway,.. I got my brake line done, and BTW Tx Firefighter, you were right, there was a union just where you said it would be, guess I was just tired and couldn't find it that day.. Well I decided to put the tires I will be using at least on the rear of the truck and take it off the stands it was sitting on, just to see what it looks like with the frame low... So here come the questions...

In this pic # 1, the frame is low but still too high I think, here is what the tank looks like, Ugly I know.. its coming out and a mustang tank going in... It still had the 2'' blocks, if I remove them will it sit lower?

Pic #2Look at all the space between the axle and the bump stop in the C- notch, that should be sitting on that axle, shouldn't it?

Pic # 3 Here's the other side, you can see the block still there, but I was told there would be no issues leaving the blocks in.... ?

Pic # 4 This is how the bags are sitting in there now, now air in them. They should be compressed more, no?

Am I being to anxious here, Ive yet to sit the front end down, cause I'm still working on the center support... have to cut out the bracket that is sitting in there no longer being used because of the full length drive shaft, but if anyone has any comments on why its not sitting as low as I think it should be, please let me know what else I need to do....

Once again, thanks everyone for your help..... To be continued.....

[SCOTI]

Originally Posted by legotech7

Just a little update on all I'm doing, Started a little late today, and had to stop early, it is 95 degrees in my neck of the woods, and the garage is about 101..... Anyway,.. I got my brake line done, and BTW Tx Firefighter, you were right, there was a union just where you said it would be, guess I was just tired and couldn't find it that day.. Well I decided to put the tires I will be using at least on the rear of the truck and take it off the stands it was sitting on, just to see what it looks like with the frame low... So here come the questions...

In this pic # 1, the frame is low but still too high I think, here is what the tank looks like, Ugly I know.. its coming out and a mustang tank going in... It still had the 2'' blocks, if I remove them will it sit lower?

Pic #2Look at all the space between the axle and the bump stop in the C- notch, that should be sitting on that axle, shouldn't it?

Pic # 3 Here's the other side, you can see the block still there, but I was told there would be no issues leaving the blocks in.... ?

Pic # 4 This is how the bags are sitting in there now, now air in them. They should be compressed more, no?

Am I being to anxious here, Ive yet to sit the front end down, cause I'm still working on the center support... have to cut out the bracket that is sitting in there no longer being used because of the full length drive shaft, but if anyone has any comments on why its not sitting as low as I think it should be, please let me know what else I need to do....

Once again, thanks everyone for your help..... To be continued.....

#1 & 3) Removing the blocks would cause it to sit even higher.

#2) When aired out, if the dimensions are set-up correctly & nothing is binding, the axle tube will hit the bumpstop. 2 things you need to determine: What bags are those & does anything appear to be binding (is the d-shaft touching the carrier bearing bracket)?

#4) Most dbl convoluted bags compress to 3". There's no weight on the rear end right now so that's part of the issue.

If you want it lower, you might need to discard the upper bag bracket. What ever the height of that is would be how much more drop you can achieve. The appropriate holes would need to be drilled through the frame rail which is more difficult vs. just using the upper bracket.

[legotech7]

No, nothing is binding, and in the pictures, the drive shaft is removed. I'll double check tomorrow, but Ive yet to ad air to the bags to see how the system works and than air it out. Perhaps that may change things.. I don't know as of yet. Hope to get the center fram support done, put all the wheels on and air it up. Right now I have the manual valves hooked to shrader valves to test the system and check for leaks,.. haven't don that yet. I hope things will just settle in. Will see.

Thanks for the input, will follow up.......

[SCOTI]

Put some weight back there when the time comes for validating things.

[legotech7]

Yep will do, thanks...............

[legotech7]

Will I got the thing thing to lay flat, I just put the wheels on in the front, took her off the jack stands and low and behold, she be low...... So I decided to start to bleed the brakes, when something hit me I just seem to forget totally.. I am' embarrassed to ask, but I will. I need to get this done... Though I haven't yet attempted to start to bleed the brakes and reading further on the subject. I had the drum set up before the caliper conversion, now the PO told me he added a brake booster and a proportioning valve to the drum set up. I remember having an issue with the rear brakes locking up on me and through the forum I remedied that by adding some washers to the MC mounting bolts pushing it forward. That fixed the brakes locking up.. But my question is , I'm not sure if the MC and booster will work with the caliper conversion. I don't know if anyone can tell me through these pictures if this looks like it might work, and if not, since I used the calipers of a 77 half ton, can I just purchase the booster MC and proportioning valve of the same year and if the booster will mount up with out issue? And if not what will I need to do to mount it correctly. I guess I didn't do all my home work on this one....

This is what I have on there now... it was for the old drum, drum set up...

The next pic is the MC, both reservoirs seem to be of the same size.. shouldn't one be larger than the other on a disk drum setup?..

[lolife99]

That's NOT a disc brake proportioning valve.
That is definitely a drum brake distribution block.
I suspect that is a drum brake master cylinder also.
I would change both.

[legotech7]

I suspected as such. Had to ask. But can I use that booster and just get right MC and valve?

Thankslolife99

[lolife99]

Originally Posted by legotech7

I suspected as such.
Had to ask.
But can I use that booster and just get right MC and valve?
Thanks lolife99

Yes.