Re: Spring Swap Thread - 1963 K15
 

The weight of the bed and fuel will bring the rear down some.

Re: Spring Swap Thread - 1963 K15
 

I was kinda thinking the same thing Jason. If it doesn't come down enough after the bed and fuel, I'll either shorten the shackles or find a big winch to hang back there lol. I still have a little ways to go before we know how it's going to turn out. We're close though.

Re: Spring Swap Thread - 1963 K15
 

I don't have any new pics at the moment but I did get the bed back on yesterday, receiver hitch and parking brake connected yesterday. After having one of the 35s blow a bead from being aired down too much, I finally got it out of the garage, connected the tail lights and took her for a spin. First impression - bring on the speed bumps!!! All I can say is that it rides a hundred times better than it did with the stock springs. There is a fair amount of body roll (which wasn't there with the stock stuff) which is kind of annoying but nothing that a sway bar or 2 won't take care of.
I am battling a driveshaft vibration that is about to make me insane. I think I'm going to be playing with shims for a while between the divorced t case and the rear driveshaft.
The 4 wheel discs work KILLAR! and although the original rear brakes needed work, I can't remember having a truck that has stopped this well. Cant wait to tow with it and really test em out.
All in all, I would recommend this for anyone who is not crazy about the way their older truck rides and would like a smoother ride. I haven't been able to get it out to any trails yet but even with the limited drive time that I have on it now, I can tell you it WILL increase the flex over the stock suspension. in fact, I may be looking at limiting straps in the near future. If anyone has any questions or wants pics of anything in particular, just say the word. I still have the fuel tank to connect and find a location for the filler. The wiring is mostly done save for the tie into the gauge and installing a resistor.
For now Im going to be tracing the source of this driveshaft vibration before I start driving it more regularly. Its one loose end that really has me worried. The thought of spitting a shaft at freeway or any speed for that matter scares the hell out of me.
Thanks to all who have commented and advised me along the way. It's really helped to have more than one set of eyes on this and your inputs have been greatly appreciated!
Chris

Re: Spring Swap Thread - 1963 K15
 

Darn you, Chris! Now I have to add front 52s to my long list of truck projects!
I'm glad it worked out so well.
have you measured your transfer case output angle amd your rear pinion angle? How far off are they?

Re: Spring Swap Thread - 1963 K15
 

Sorry Jason. It will be a breeze for you though. You've got some pretty mad skills! I've got the trans to tcase joints parallel and a working angle of 2 degrees. The tcase to Pinion was parallel as well with around 5 deg working angle but it felt like I was getting a little axle wrap as I would take off so having nothing but a 5 degree shim, I put it in and pointed the Pinion down. The vibration did change but its a little stronger. I almost think that the tcase may be moving around a little too. More investigating. May have to mount a GoPro underneath to see what's going on

Re: Spring Swap Thread - 1963 K15
 

And get on those 52s! You won't regret it!

Re: Spring Swap Thread - 1963 K15
 

nice project along w/ the progress =0)

Re: Spring Swap Thread - 1963 K15
 

Thanks. So far its been the best upgrade (next to getting the truck in the first place) that Ive done to it.

Re: Spring Swap Thread - 1963 K15
 

On the rear 63 did you just move the front stock frame hanger forward ?

Re: Spring Swap Thread - 1963 K15
 

The stock hangers (all 8 front and rear) were removed. Once you bust the first rivet out, they're just repetitive after that. I installed the rear / rear hanger from DIY and the front / rear is from ORU. Both are excellent quality.

Re: Spring Swap Thread - 1963 K15
 

I had a head scratching vibration once after i switched from a SM318 to a SM420 and had a drive line built to fit.

I will spare the lengthy version, but what mine ended up being is one of the nylon washers that fits between the u-joint cap and the actual cardan cross portion itself. While I was installing the drive line, both u-joint caps at the differential end came off. I simply put them back on except one of those little washers stuck to the cardan cross, the other stuck inside the u-joint cap...I failed to notice this when i put the caps back on...and ended up having one cap with 2 washers and another with zero. This obviously off-centers the drive line and thus causes a vibration.

Not all u-joints have those washers in them, but if yours do, you might give it a look. It just about drove me nuts but it ended up being that simple.

Just an idea.

Great thread and great work on your truck.

Re: Spring Swap Thread - 1963 K15
 

I love this truck! Looks great Chris!

Re: Spring Swap Thread - 1963 K15
 

Thanks Larry, after seeing the work that you and some of the others on here do to their trucks, the compliments are quite humbling for me. I've got a few more things to finish up to close out this thread (gas tank, and front sway bar) but I'm in a sort of holding pattern at the moment. Got a refi and some family stuff going on. Hoping to get back to it soon once the dust settles. Thanks again for the kind words Larry!
Chris

Re: Spring Swap Thread - 1963 K15
 

Was the truck lifted already before you did this spring swap? I saw in the first post you mentioned you had 5 1/2" blocks in the rear.

Re: Spring Swap Thread - 1963 K15
 

It had the stock "I beam" style blocks when I got it. Not sure if it t was lifted when I got it. It still had the original grease pin shackles and as far as I know, there are no lifts available for that style. It did have a add a leaf in the front which I think added to the poor ride quality. Right now with the 63"-52" swap, it looks to be maybe 1/2" -3/4" higher than before. Believe me that was more of a stroke of luck than engineering in my part! And I will say it again - best upgrade for this truck yet! Hell, the wife will even ride in it now. She won't admit it, but it does ride better than her '04 Yukon.

Re: Spring Swap Thread - 1963 K15
 

Ok, that makes more sense. This swap is definitely on my list for my '70 GMC. The few of these swaps I've seen done on 67-72 trucks they've all said the 52" springs gave them 3-4" of lift in the front. I wouldn't mind that much lift but I do appreciate the truck being stock height.

Re: Spring Swap Thread - 1963 K15
 

The 60-66 4x4s have a much higher stock height than the 67 and up pickups.

Re: Spring Swap Thread - 1963 K15
 

Good to know, thank you

Re: Spring Swap Thread - 1963 K15
 

Interesting. I didn't know that but it makes total sense. I always used to have people ask how much I had lifted it. I never really knew what to say except for that it was stock which usually left people looking at me like I was an idiot. Lol. Thanks Jason

Re: Spring Swap Thread - 1963 K15
 

The '60-'66 K10/15/20's were pretty tall from the factory. I saw this one on ebay a while back, and the seller said it was on 35's, no lift.

Re: Spring Swap Thread - 1963 K15
 

One more question, I didn't see it mentioned anywhere but are those rancho shocks?

Re: Spring Swap Thread - 1963 K15
 

Yes they are RS9000S. I got them when I first swapped the axles a few years ago. The springs were so stiff that I never noticed a difference after adjusting them. Now it's night and day when I adjust them.

Re: Spring Swap Thread - 1963 K15
 

You're a step ahead of me haha my next question was going to be if you had adjusted them yet. Thanks for being the guinea pig on this :lol: looks like you did a top notch job

Re: Spring Swap Thread - 1963 K15
 

I just got tired of waiting for someone else to be the test dummy. I tell ya though, had this not worked, I'd be sleeping in the kids treehouse out back. Lol. Thanks for the compliments.

Re: Spring Swap Thread - 1963 K15
 

I've been contemplating the 52" front spring sway for a while, but just haven't had the time or space to dive into it yet. I was also under the impression that longer rear springs wouldn't make enough difference to justify all the work, but it seems you've proved it to be well worth the extra work.

Re: Spring Swap Thread - 1963 K15
 

Hey Zach, yeah it was definitely worth all the work in my mind. I really like driving the truck again. Although I think that the rear 56 swap is just about moving the rear hanger, I've had several trucks with the 56s and a few with the 63s. There really wasn't a comparison for me. If I ever need more capacity, I'll dig up some 63" 3/4 ton springs and mess with those.
BTW, where in Loveland are you? My Father in Law lives there. Been there a few times myself for Thanksgiving. Real nice country.

Re: Spring Swap Thread - 1963 K15
 

Yeah I would probably go with some 3/4 ton 63" springs to keep the load carrying capacity. Did the 63" springs interfere with your bumper brackets at all?
And I'm in South Loveland up on HP hill, and it is indeed a nice place.

Re: Spring Swap Thread - 1963 K15
 

i'm just about to this point with my k20 and have some 3/4t 63's and newer 2500 springs as well. i have few questions if you don't mind.

where did you get your new perches and top plates? my local offroad shop is out of them at the moment so i might as well order some.

do you think the rear hanger will interfere with using a modified drop hitch or bumper brackets? i'm wondering if i should use my 2000 model springs for better clearance?

anyways nice truck and pit! my pits 15 yrs old and always been a great shop dog,rick

Re: Spring Swap Thread - 1963 K15
 

Hey Zach, Yes the DIY brakes did interfere a little with the bumper brackets. I believe that the two brackets on each side were originally supposed to "sandwich" the frame rail. Mine came with both brackets (2 on each side) bolted to the outside of the frame rail. I re installed the brackets the same way that they were because the rear cross member prevented me from putting it back the way it was stock. It worked out well though. I trimmed the bracket that was up against the frame enough to clear the hanger. The outer bracket actually uses the same bolt as the top rear spring hanger. I'll have to get some pics of it. Its just a little difficult to explain.

Re: Spring Swap Thread - 1963 K15
 

Rick,

My last post kind of described the issues that I had with the bumper brackets. Not sure if you have the same kind. As far as the drop hitch, I got mine with the fuel tank and skid plate from an '89 Blazer. The hitch went on fine although the bottom bracket of the shackle did make it necessary to shim the back half of the hitch down 1/4". Having the tank in at that time made those bolts a PITA to install even with the bed off! lol. The top spring plates were from Ruff Stuff in Roseville, as were the u bolts. Top quality and fast ship. The spring perches were Summit but I got them before I found R.S. He has them too.
I just checked out your build. Nice work. Looks like its coming together pretty fast. Gonna be a great ride when its done! Keep up the great work.

Re: Spring Swap Thread - 1963 K15
 

Did you get your drive shaft vibration issue fixed?

Re: Spring Swap Thread - 1963 K15
 

For the most part yes. When I installed the TC, I must have been in a hurry because it was way off. I've got it corrected as best I can right now. Occasionally it will have a slight vibration when Im lugging 4th but other than that, its been great. I almost think that the divorced T cases need some sort of brace to keep it a little more rigid. Thats another project for another day. The DS vibration almost drove me insane. Just had to keep on messing with it.

Re: Spring Swap Thread - 1963 K15
 

Hi 63genIII

Could you please let me know the parts number for the REAR Shackles and hangers ? I am trying to say all the parts which attach the REAR springs to the frame. Read trough your tread several times and could not positively identify them.

Just removed all the rear suspension parts on my 64 4x4 suburban and the Hangers i have wont do it.

Thank You
Eddy

Re: Spring Swap Thread - 1963 K15
 

Top new springs bottom old ones.

Re: Spring Swap Thread - 1963 K15
 

Will do Eddy. I think I just found the receipts for them the other day while cleaning the garage. Ill take a look in a few.

Re: Spring Swap Thread - 1963 K15
 

Ok Eddy, I found the receipts. For the front hanger of the rear springs, I used an ORD GU28010 - 1 which is listed as a "shackle flip kit for 67-72 GM

For the rear of rear hangers, I used DIY 4x4 item #00590ka "first gen shackle flip and switch w/ 4.5" shackles."

I used the ORD up front and had to flip the spring front eye to the rear since the bigger eye on the front of the spring created a clearance issue with the hanger (which really wasn't sized to anchor the front of the spring anyway).

That said, I didn't know that the differences in frame widths that occurred throughout the years were compensated for by moving the hangers inward or outward so that the spring perches on the axles remained somewhat the same. I wasn't aware of this possible problem because the 2005 14BFF needed new spring perches anyway. Im guessing that you are trying to re use your existing spring perches so I would recommend taking some measurements. If you need measurements off of mine, I can get them tomorrow.

Re: Spring Swap Thread - 1963 K15
 

Cool i found them, Thx a lot will make it easier i hope. Updates will be posted as available.

Re: Spring Swap Thread - 1963 K15
 

I was wondering what year of truck did you get the 63" springs from? I am just getting ready to start my 64 k10 build and I am looking at doing the same spring swap you just did. Great work and pics.

Re: Spring Swap Thread - 1963 K15
 

Pretty sure that they came off of an '07 Silverado 1500.

Re: Spring Swap Thread - 1963 K15
 

I'm sure there are many variations, but GM started using the 63" springs in 88 on the GMT400 trucks.