Suspension help

[Straight six]

Well I'm getting ready to install my 4.5/6 drop kit for my 78 c15 lwb Heavy half. Also I'm rebuilding both front and rear suspension as well. Couple question I have are when installing my control arms do I keep all shims on the uppers? Are there any special tips I need when tackling the front end? And the rear when replacing old leaf springs with my new ones will they just fit right in place no special tools? And can ANY parts that I'm removing potentially fly out and whack me in the head front springs or rear leafs?? Here is a pic of some of the parts. And almost forgot do I need another pair of jack stands to hold the rear end up when removing and installing leafs or just use the jack and balance it?

[sparks427]

If your not careful the front springs can come flying out at ya when ya pop the spindle lose, I always put a jack under the lower control arm when taking them apart to prevent that, then let the jack down slowly and it should fall right out. And I would put the rear axle on stands because it would such if it fell off the jack and broke the rubber brake line, would throw a whole bunch of other issues in the mix. And I'd leave what ever shims are in the front there, then immediately get it aligned and they will take out or add what ever is needed. Just my .02! Good luck!

[Tx Firefighter]

Well played sir. That's a quality pile of parts there. They will serve you well for many years. Lots of American made stuff in that picture.

In the front, just keep the jack under the lower ball joint until you remove the nut and slowly let it down. The spring will come down with it. No need for concern other than it falling out and hitting your foot if you're not careful.

When you go back together with those drop spindles, you're gonna have to slightly bend the metal ends of the brake hoses near the caliper to clear the spindles. It's no big deal. I use a long prybar to gently nudge them downward so they clear. Takes five seconds per side.



Install upper ball joints with bolt heads down and nuts on top. There should be a little piece of paper in the boxes reminding you to do it this way. About 80% of the people on here ignore that and do it wrong with the bolts pointing down and nuts underneath. There is a valid reason to do it right.

Leave the big nuts on the control arm bushings loose until the truck is sitting down under weight. Then tighten. Never tighten them when the suspension is hanging looses. It preloads the bushings and the ride suffers. Bolt it all together and complete then when the suspension is compressed, you're ready to tighten them.

Go ahead and reinstall the upper control arm shims in the places where they came out of. Keep track of them upon disassembly so you get the right stacks back in the right places. Your alignment guy will take it from there. The pre-existing shims packs will set your basic alignment to allow you to get it to a shop where it can be checked and adjusted.

In the rear, put frame on jack stands. You can balance the rearend on the jack. There are no special concerns there. Just don't drop the leaf springs on your fingers. When you get it all installed, tighten u bolts and leave the hardware on the ends of the leaf springs and shackles loose. Then set truck fully down on the ground under its own weight before you tighten them. Never tighten leaf spring bolts when the spring is unloaded. Only at ride height. Set it down, bounce the truck a bit with your body weight then tighten shackles and leaf spring bolts. Same deal as the front control arm nuts. You don't want to cinch them down then compress the suspension because it will stress out the bushings and they'll be preloaded under tension.

[tinydb84]

Good advice so far. My advice:

Take your truck to a steam cleaner beforehand. For ~$100 bucks it makes working on a dirty greasy truck a lot less of a pain.
Plan for it to take longer than you think it will.
Use penetrating oil on any bolts you are going to remove a few days ahead of time.
Use new U bolts. Don't bother trying to unbolt the old ones, just cut them off.
Bolt the springs in first then tighten down the rearend (Don't attach the springs to the rearend first)
Match the length of your new tie rods with the old ones before installing.

That is all I can think of for now

[sKnNyPpY]

I used two sets of jack stands (4 total), a jack stand style jack, and a floor jack when I replaced my leafs. Two stands under the frame, two under the axle, and the jacks to get them there. My leafs did come out with one heck of a thwap under the bed so might want to read up on what side to release first.

[Tx Firefighter]

Respect the weight of the leaf spring. It won't bite you, but it will mash you if you drop it. I was doing a flip kit on a buddy's truck a few months ago and got in a hurry.

I'll let the pictures tell the story.







I finally has to let the doc do some surgery on it.



Pure agony.

[Straight six]

Great thanks for the help guys much appreciated. Thanks for the leaf spring info that would been my finger if you didn't tell me about it lol...

[sparks427]

Holy cow! That finger looks horrible! Hope it's better!

[Straight six]

Now I'm a little worried about my new leaf springs with the 6 inch drop will i have to remove leafs to make level with the 4.5 front drop? Will I have a big stupid rake? Will it still sit level?

[tinydb84]

Originally Posted by Straight six

Now I'm a little worried about my new leaf springs with the 6 inch drop will i have to remove leafs to make level with the 4.5 front drop? Will I have a big stupid rake? Will it still sit level?

You should sit level with that drop (maybe a slight rake). If you pull leafs you will sit even lower in the rear (even wit the flip kit).

[sKnNyPpY]

I did a 2.5" spindle, 1" drop springs, new ball joints front, djm flip and new leaf springs rear and sit pretty level. You should be pretty close to level

[Straight six]

Ok I have another dumb question about my rear leafs install. After I put the truck on jack stands remove tires now when I jack up the rear axle does that take pressure off the u bolts so they come off easier? I just tried to see if I could turn them with the truck still on all fours not lifted up and they didn't budge at all.

[Tx Firefighter]

Trying to unbolt the u bolts with hand tools will make you want to kill yourself.

You really need to bang them off with an impact gun or just cut them (angle grinder works great) since you have new ones. Doing it by hand is just pure misery.

[Straight six]

Shoot that sucks.. All I have is hand tools unfortunately.. Is there anything I can do to make it easier? I have been soaking them with pb blaster since Monday. I really want to start this tomorrow..

[Tx Firefighter]

Harbor Freight for a 4.5 inch angle grinder and a pack of wheels for it. Should be out the door for 30 bucks. You're gonna need it to trim your lower control arms and cut the C notch anyway.

[tinydb84]

They have a sawzaw on sale for 20 bucks too. I beat the crap out of mine.

[Straight six]

Took the advice bought the HF grinder best thing I could have done cut those UBolts like butter And the leaf spring bolts as well. I was able to get the back done freakin amazing I'm so happy I'll post pics later at home on the good old computer.. The one question I do have is what size are the rear upper shock mount but size I some how misplaced them idk I'm a idiot..

[Straight six]

Nut size sorry

[Straight six]

I figured out the NUT size..... Now the issue is how do I bend the brake hose when it won't fit until it's bent. It's so tight I can't even get it to go on. Is their a way to bend it while it's not on the the caliper?

[Straight six]

I'm stuck at the brake hoses for the life of me I can't figure out how to bend them. That's the last step of this drop need help!!!

[lolife99]

I ususally tweek my brake hose when it's installed on the caliper.
You can always separate the upper balljoint and back the upper a-arm away until you get it bent.
I use a "line wrench" to tweek the steel part of the brake hose.

[Straight six]

Well the separating the upper ball joint worked great I was able to get the brake hose ends bent perfectly.. Well everything is finished with the drop. The problem I'm having now is that my front left tire is leaning inward from the top. What could this be the problem??? Sorry no pic of the left side will get one later along with a bunch more or the process..

[tinydb84]

You need to go get an alignment now. Its increased negative camber due to the shorter springs up front.

[Straight six]

Is it safe enough to drive home with 13 mi away?? And it's weird the right front seems to be sitting straight.. The alignment shop is two min from my house also

[tinydb84]

Yeah it should be fine. You will wear down your tires faster though. The number of shims on the upper control arm determines the camber angle. There are a number of reasons it one tire could be more upright (previous spring was already sagging, shims might be missing, etc) no big deal though.

Just get it to the alignment shop soon and you will be a happy camper.