Power brakes & Disc's up front, What all do I need?

[Litemup]

The Truck: 1968 GMC


This is a more hypothetical question than anything considering I don't have the truck yet but I'm preatty new here and I was wondering if ya'll could help me out.

The plan is to put power brakes and discs up front on a truck with drums all around and no power brakes. Basically I'm wondering what do I need and whats involved with the swap.

I took a look at early classic's website and it looks like I can buy a brake booster there as well as disc brake swap stuff. Is the stuff I buy on there all I need or do I need new lines or anything else. And does anyone know if this is a bolt on affair or do I need to do some welding. Any help on this is really apprecaited.

Thanks in advance!

[poorboy]

You can get a cross member and suspenion from I belive a71-87. or you can try this.http://67-72chevytrucks.com/vboard/s...ad.php?t=35042

[Fred T]

This makes it decision time. Do you want to go 5 lug, or stick with 6? Also, do you want to lower the truck? If lowering, the drop spindles are the way to go. If you want to buy used parts and 5 lug, grab a crossmember from a 71-87. 6 lug and used parts are in the thread from poorboy.

Whichever route you go, I would recommend replacing all the front suspension parts with new Moog components. That means tie rod ends, ball joints, control arm shafts, pitman arm and idler arm. Makes a huge difference in handling. Some of the vendors sell the entire package.

It's also a good time to replace the front brake lines. The lines on the crossmember usually have rusted and get thin. The kits come with new brake hoses, something else that needs replaced if you go the used route.

You shouldn't need to do any welding, it's all bolt on stuff.

[mnunn454]

Ditto what Fred said. It's all bolt-on once you know exactly which direction you want to go with the lugs, ride height and budget for the upgrade. Luckily there are plenty of suppliers nowadays for our needs. Wasn't always that way.

One thing to consider is if your engine is radical/has low vacuum at idle, you should probably avoid the smaller diameter power brake boosters.

My 69 has been retrifitted with 71-up 5-lug power disk brakes, spindles, M/C & booster. The engine only pulls 8" of vacuum at idle and about 15" highway, requiring a little extra foot pressure at traffic lights. A smaller booster would make this setup intolerable at best, and dangerous at worst.

BTW, love your avatar

[Litemup]

Thanks guys alot of good info here.

So heres what I plan to get out of it... I would be dropped probably in the 5" area so drop spindles would be something that would be happening. I'm not sure what the advantages are between the lug patterns, can anyone edjucate me? Now as I understand it I can get drop spindles for disc brakes so that takes care of the disc brake's, but I'm assuming I would still need a kit that would include the calipers and brake lines and pads. The current engine is a preatty tame 350 that has an RV cam in it. I think I would still get a full sized booster, at some point I'll be building a big block for it and at that time I'll probably look into something else.

The truck has no power steering either and its desicion time for me as well on that end, the linkage up front is different for a power steering set up so if I got all new parts up front I think I would have to know before hand If I was going to put power steering on it. Do you guys think power steering is a neccesity for a daily driver?

Heres the current list of what I'd be buying assuming I'm not going to power steering:
Brake booster (Normal size)
Drop Spindles for disc brakes
Caliper kit (Calipers, lines, pads)
Rebuild kit for front end

I think that's all I need assuming that theres a vendor I can get all this stuff from, money is'nt super tight at the moment and with brakes I tend to just buy new and be safe.

[boraxman]

I pieced mine together on my truck and it was a PITA. Lots of time gathering parts, wrong parts sent(online) and returned and sent again, turning rotors, auto parts store runs like crazy, etc.

The way you want to go is, kit or cross-member swap period. If I was doing it over this would be the way.

As far as 5 lug, it will give you more wheel choices, but you would also want to do the rear axles to 5 lug also, which on a 68 is going to be a whole different deal as it is to narrow for a direct 5 lug axle swap...would be easier to swap to a late 70 to 72 rear end.

Good luck and it is worth the effort.

[poorboy]

The lug pattern I think is more of a personal preference. You could buy a kit that comes with the calip,rotors,and pads. I fell that some companies charge too much for that stuff. Your local auto parts store should have it all in stock. Just get it for whatever year spindels you end up with. the power steering is not required for a daily driver. But depending on your wheel and tire combo manual steering might old real quick.

[Litemup]

Originally Posted by poorboy

The lug pattern I think is more of a personal preference. You could buy a kit that comes with the calip,rotors,and pads. I fell that some companies charge too much for that stuff. Your local auto parts store should have it all in stock. Just get it for whatever year spindels you end up with. the power steering is not required for a daily driver. But depending on your wheel and tire combo manual steering might old real quick.

I don't think I'll be putting big wheels on it, probably some nice reconditioned stockers or something, will definitly be something old school.

Now if I buy drop spindles from lets say early classic, do I need to buy there disc conversion as well or can get the discs and calipers and lines and all that from somewhere else.

[poorboy]

You can get the disc from any where. They are made to accept stock componets.

[boraxman]

I guess I should add I was trying to do mine as cheap as possible, so a few junkyard runs, online shopping, trying to save where I could. It still cost nearly as much as a kit.

[poorboy]

http://mcgaughys.com/ has a 6 lug kit that comes with everything. Rotors.hoses,bearings,ect for $239 and a 5 lug kit for $229. I can't find it on the website but it's in the add on page 7-8 of Feb 07 Classic Trucks

[poorboy]

That's probably one of the best deals I've seen And they have drop spindels for $230

[Litemup]

Thanks alot for the information guys!

[Bob Moore]

Litemup - head out to the Pull a Part at 112th and Steele. Buy a complete crossmember from a 73 to 87 1/2T 2wd. Unbolt the intermediate steering shaft from the PS box. Unbolt the steering box from the frame. Unbolt the idler arm from the frame. Unbolt the motor stands from the crossmember. Unbolt or cut the brake hoses. Unbolt the crossmember from the frame(7 bolts on each side). Take it home - take it apart and return the spindles and the springs for money back.

You can clean it all up and replace any worn parts. Order the 73-87 heavy duty drop spindles(1.25 inch thick rotors) and lowering springs from Early Classics. When you are ready to swap just drop out your old crossmember and install the new CLEAN parts. I would strongly advise the PS upgrade. Get the sway bar brackets(lowered) from ECE also and upgrade to the 1 1/4 inch sway bar.

[bluec10]

Check out this thread:

http://67-72chevytrucks.com/vboard/s...d.php?t=221874

I'd like your opinion.

[71Chev]

McGaughey's is what we carry for the 60-72s.
http://www.gmcpauls.com/Brakes&Steering.htm

[68GMC454]

i got a 68 gmc to..when i do it im going to do the whole cross meember swap..i already have power sterring on my truck,,would still rather do the swap..i figure i can get the whole crosmemebr and everything i need for it for less than 100..00 but i got a friend..so for me this is the route to go..but you might want to just buy the kit,,not sure what they cost...i will get the rear end from the same truck when i do this..so you might just want to buy a running cheap truck,,then you might have some extra parts to sell,,then take the rest of it to a recylcer that buy scrap metal by th puond..you might get lucky and have hardly any money in the whole swap..