Lowering the rear of a GMC

[bmur66]

Not sure that I am doing this yet but if a guy wanted to lower a GMC with a leaf spring rear end, what would be the best way? I am only talking a few inches to go along with 2 1/2" drop spindles. I want to keep the same "rake" it has now. There are hard rubber blocks between the axle and leafs. Would it be as simple as cutting them down? There is not much room to use longer rear shackles and they may interfere with my fuel fill hose.

[tincan1966]

This is our old '66 Shop truck. Was lowered about 2 1/2-3 inches, by removing 4 leaves from the rear springs. when doing this, I recommend leaving the very bottom leaf, then removing the next 3-4 up from that.

Editted- sorry wrong pic, can't see rear wheels! LOL

[61_FL_Apache]

What about flipping the rear? Put the rear on top of the springs instead of underneath. That will give you at least a 4" drop.

[tincan1966]

Apparently I do not have any good side view pics any more of it before it was wrecked. But for referrence, I am 6'1"
Truck is sitting on 215/75/15 front tires, and 235/70/15 rears
1 1/2 coils cut from front springs, 4 leaves out of rear leafs.

250cid 6 cyl w/ granny 4 spd.

[bmur66]

I will have to look at it to see if flipping is possible. I would only want to drop it about 3" and flipping it may be too much. How was the ride with 1 spring Tincan? I won't be hauling anything other than arse. I also have a ladder bar setup on it that I need to consider. I have some adjustment with rod ends but I don't think I could go too low.
Like I said I am not sure I want to do this yet but when I put fronts disks on it I will have to decide if I want to use drop spindles.

[tincan1966]

Flipping the rear axle to on top of the springs will be a drop of about 6+ inches, and you'll have to re-locate the shocks. Also you will most likely need to "C" notch the frame, as the axle will be hitting the frame on even the slightest bumps.

If you're only looking for 2-3", I would either remove a fewleaves or de-arch the main leafs.

[AndrewJoey]

Originally Posted by tincan1966

Apparently I do not have any good side view pics any more of it before it was wrecked. But for referrence, I am 6'1"
Truck is sitting on 215/75/15 front tires, and 235/70/15 rears
1 1/2 coils cut from front springs, 4 leaves out of rear leafs.

250cid 6 cyl w/ granny 4 spd.

I'm doing the same thing to my '66 + 2" drop shackles, question - Did you have to change your shocks?
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[tincan1966]

Originally Posted by AndrewJoey

I'm doing the same thing to my '66 + 2" drop shackles, question - Did you have to change your shocks?
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I did not change them. should I have? Mostly likely should have put on some drop shocks with more travel, just to be smart. I really think it bottomed on the bumpstops befor ethe shocks bottomed out- never had a problem.

[boucher racing]

I have a GMC and did what TINCAN did. But cut 1 3/4 coil off front and removed 5 leafs from the rear. It is the lowest I can go without more serious suspension mods.

In terms of shocks, read this:

http://67-72chevytrucks.com/vboard/s...d.php?t=573266

Boucher'
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[AndrewJoey]

Originally Posted by boucher racing

I have a GMC and did what TINCAN did. But cut 1 3/4 coil off front and removed 5 leafs from the rear. It is the lowest I can go without more serious suspension mods.

In terms of shocks, read this:

http://67-72chevytrucks.com/vboard/s...d.php?t=573266

Boucher'
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How much did your front drop with the 1 and 3/4 coil cut? I'm wondering if there will be too much play when I do it. I'm taking out the leaf-springs tomorrow. Fun to see the truck change with each day's work.
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[AndrewJoey]

Well, I worked on mine all day today. I spent most of the day tapping threads in the leaf spring brackets. After removing the 5 leafs there wasn't enough thread left. It was not fun, but I got it almost done. One side is in tomorrow we see how she sits. Here's a few pics. I too hope it looks good, or a flip will be in order.



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[bmur66]

Wow. How many leafs did you have on each side? I have 5 and it's a 3/4 ton. Do you have a spacer block between the leaf and axle? Thanks for posting up the pics.

[tincan1966]

If I remember right, ours had 9 leaves on each side. I left the very bottom one(it is thicker and straight) and removed the next 4 up from that.

[bmur66]

Interesting. I am guessing the previous owner of my truck has already removed or changed leafs and added a spacer block about 3 1/2" thick in their place.

[boucher racing]

I should have mentioned that I had to go get new U-bolts bent with shorter threads. If you are really close with the threads, you can take a stubby one you took out and put it on the top plate. It should have no bearing on suspension, just a spacer so the threads can reach.
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[AndrewJoey]

Originally Posted by bmur66

Wow. How many leafs did you have on each side? I have 5 and it's a 3/4 ton. Do you have a spacer block between the leaf and axle? Thanks for posting up the pics.

No problem, pics always tell the story. There were 10 leafs per side. This truck was a class B, up to 10,000.

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[AndrewJoey]

Done! Here's a pic, the body line of the bed will come up about 3/4" when I put in a new wood bed.

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[Vernski]

Originally Posted by tincan1966

If I remember right, ours had 9 leaves on each side. I left the very bottom one(it is thicker and straight) and removed the next 4 up from that.

I took my leaves off and went to Pohl springs to have them re-arched as you could see it sitting higher on one side. Mine had 8 in one side and 9 on the other, the truck came off a ranch in western Montana. The PO must have put in the extra leaf so 3 on one side and 4 on the other came out. The lady we bought it from said it could haul allot of hay and it is a 1000 series BTW. I put some DJM 3" coils in the front, the back came down about 5'' and sits about level I included some pic's..Vernski

[AndrewJoey]

Originally Posted by Vernski

I took my leaves off and went to Pohl springs to have them re-arched as you could see it sitting higher on one side. Mine had 8 in one side and 9 on the other, the truck came off a ranch in western Montana. The PO must have put in the extra leaf so 3 on one side and 4 on the other came out. The lady we bought it from said it could haul allot of hay and it is a 1000 series BTW. I put some DJM 3" coils in the front, the back came down about 5'' and sits about level I included some pic's..Vernski

Looks great, good job. That is a beautiful truck. I haven't touched the front of mine yet, I may leave it for now, not sure.
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[gimmy 64]

I have 2 1/2 dropped spindles and 2 in. springs up front. in the rear I used 2 in. longer shackles and remover the 3 short springs. it is about 4 inches lower. but this is a 1/2 ton also

[gimmy 64]

here's a picture --sorry

[AndrewJoey]

Originally Posted by gimmy 64

here's a picture --sorry

Looks great, good patina. Ya, I need to lower my front now, the more I look at it. I guess it's time to save some $$$. I don't want to just cut the springs. I want it to be safe and not have it jump around when I hit a bump.
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[Vernski]

Originally Posted by gimmy 64

here's a picture --sorry

Wow sorry for what! Love the door art..Vernski