77 lowering advise

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Grit dog

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Mine are for the BIG TEN stock brakes, when I said big brake kit I meant Willwood, Baer etc. Thats why I have them just sitting the Willwood's use a different spindle.
Oh. Hmmm. I may take you up on that.
 

xm20k

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Just let me know I'll have to pull those heavy a$$ rotors and shields and clean them up. I've been tripping over these things in my garage for almost a year now LOL.
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Thanks. You guys are confirming why I’m looking at spindles only.
My question was only because 2.5” is common and 3” is not. Other than small diameter rims having clearance issues with 3” spindles, I’m hearing there aren’t any other big considerations going 3”?
I don't have any direct experience with it but have heard it said that some of the 3" spindles enlarge the turning radius a bit. But I remember that was a claim with the spindles I used on my 04 Yukon years ago and there was no noticeable change. Other than that, no issues I can think of. I've debated swapping my 2.5s for 3s and a new set of springs so I can get my alignment better, just haven't done it.
 

dirtscoots

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For springs and shocks anyone have any recommendations? I think 2 lowering springs should be more then the cut springs I have and achieve actual suspension to keep my front end off the ground.
 

TotalyHucked

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For springs and shocks anyone have any recommendations? I think 2 lowering springs should be more then the cut springs I have and achieve actual suspension to keep my front end off the ground.
I would suggest ordering some replacement OE springs (Rock Auto likely carries them) and just cut 1 coil off. As I said earlier, all aftermarket drop springs for these trucks are too soft. For shocks, Belltech SP are my go-to's for anything I lower. Just regular drop shocks for the front, the rear you'll likely need drop shocks and extenders as well.
 

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Thanks for the advice.
Truck’s a F44/Big 10 so it has the “big brakes” already lol. Assuming you meant that and not aftermarket.
Appreciate the offer but I need the 1.25” rotor spindles and kinda honing in on 3” as it’s got 20s now and if I ever went back to steel wheels they probably wouldn’t be smaller than 18s. Not everyone’s cup of tea but I like the look of bigger rims in general.
No chance of fenderwell headers or anything else getting in the way there. I took that into account when mounting the side pipes already.
Took a bit to get the pipes where they “look” like they’re in the right place, didn’t intrude into the wheel well too much and could actually attach them to rockers without major changes in the bolt up locations.
I like the side pipe look enough that when/if I put something under the hood with more than 200 ponies I’d probably use exhaust manifolds or shorty headers so I could plumb them back up to the side pipes. Long tubes would work but the exhaust would have to do 2 u-turns before reaching the pipes with long tubes and standard collectors.
Pipes are another reason I’m stopping at 2.5-3” in front. Rear will end up in the 4-5” range with lowering leafs. But with them pipes I think it will have the illusion of being more slammed than it actually is.
Mostly though due to simplicity. Can bolt on spindles and leafs easy peasy. Anything more and there’s a lot more work involved.
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Is this how the trucks sits before the drop? I'm curious what a 2.5"/4" drop looks like. I've got a 77 c15 and dont know if I want to go that route or more with an axle flip....
 

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Is this how the trucks sits before the drop? I'm curious what a 2.5"/4" drop looks like. I've got a 77 c15 and dont know if I want to go that route or more with an axle flip....
Yes that’s OE suspension.
Here’s my thoughts on the rear drop. Measure and do the math but you won’t get but maybe an inch of travel if you do an axle flip and don’t notch the frame.
Other options, drop hanger and shackle can get about 4” plus whatever you pull out of the spring pack. But you have to do some major surgery on the front spring mounts which looks either very difficult without removing gas tanks or easier if tanks removed.
3” or 4” drop leafs are simple bolt in for not much more $ than the above with about 80% less work.
I found a few good pics of 2.5/4 and that’s the range I’m shooting tor whether I go with 2.5 or 3” drop spindles and for sure drop leafs in back.
 

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Yeah that's kind of where im at, not sure if I want to notch frame. I love the looked of a dropped truck with an axle flip, but I think I want to try the absolute maximum I can go without flipping/notching.
 

xm20k

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This is the rear of mine with no notch and stock 1/2 ton spring packs and 9" with built in flip mounts even with the original BIG TEN spring packs and 12 bolt there was plenty of space with the bump stops and mounts removed the top spring is in the same place the extra leaves just made the caltracs mounts sit closer to the ground under the leaf pack.
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Fat 454

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do flip kits ever fail ? - I mean I'm sure people no longer use their lowered trucks to haul or tow, however just looking at it from a "structural" perspective, all weight and force at the rear is now directed through only a pair of U bolts and their threaded nuts. OEM mounts the leaf pack over the axle, so all weight is transferred directly into / onto the axle shaft and then to the wheels.

Always been interested in thoughts on this?...
 

xm20k

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do flip kits ever fail ? - I mean I'm sure people no longer use their lowered trucks to haul or tow, however just looking at it from a "structural" perspective, all weight and force at the rear is now directed through only a pair of U bolts and their threaded nuts. OEM mounts the leaf pack over the axle, so all weight is transferred directly into / onto the axle shaft and then to the wheels.

Always been interested in thoughts on this?...
To get enough weight in the bed of one of these to break stuff the frame would meet and rest on the axle before that point, then you'd have other issues like steering being super twitchy and possibly bending the axles out by the flanges.
 

TotalyHucked

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do flip kits ever fail ? - I mean I'm sure people no longer use their lowered trucks to haul or tow, however just looking at it from a "structural" perspective, all weight and force at the rear is now directed through only a pair of U bolts and their threaded nuts. OEM mounts the leaf pack over the axle, so all weight is transferred directly into / onto the axle shaft and then to the wheels.

Always been interested in thoughts on this?...
I've seen several fail but always due to poor quality parts or improper install, never from the load. I've had my truck loaded TF down several times and never had an issue with it, my only issue was driveshaft clearance :lol:
 

Grit dog

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Yeah that's kind of where im at, not sure if I want to notch frame. I love the looked of a dropped truck with an axle flip, but I think I want to try the absolute maximum I can go without flipping/notching.
Slide under your truck with a tape measure. A flip is 6-7” with no ability to make it “slightly less” unlike the multitude of options if you don’t flip it.
Axle flip is a no go without a notch on C10s like ours.
 

xm20k

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I've seen several fail but always due to poor quality parts or improper install, never from the load. I've had my truck loaded TF down several times and never had an issue with it, my only issue was driveshaft clearance :lol:
A 5" diameter aluminum driveshaft did need some cab floor clearance nothing the old Tonya Harding couldn't handle.
 

xm20k

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Slide under your truck with a tape measure. A flip is 6-7” with no ability to make it “slightly less” unlike the multitude of options if you don’t flip it.
Axle flip is a no go without a notch on C10s like ours.
The only real way to know is measure the axle and perch height and see what that leaves you over the spring to frame rail, for sure you will need to remove the bump stop and its mount, 2 rivets on each. My flip kit fit with 3 inches between the top of the axle and frame rail when it still had the stock BIG TEN leaves and 12 bolt and it did not hit, but I've heard others weren't so lucky.

There is a shorter shackle available, but it doesn't do much.

Unfortunately, don't have a pick of the flip kit with the stock parts still in it.
 
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