Author Topic: leaf springs  (Read 12910 times)

Offline Als87

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leaf springs
« on: November 15, 2013, 07:12:21 pm »
I just replaced all 4 shocks on my lifted 87, but it still rides kinda rough, some improvement but not what i was expecting. Could my leaf springs be wore out? Would that make it rough? How much arc should they have the front ones don't have much arc left.
'87 Shortbed 4x4
350, 350thd
4" suspension lift on 35's

Offline Irish_Alley

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Re: leaf springs
« Reply #1 on: November 16, 2013, 12:06:15 am »
to many leafs can make for a harder ride. you can take one or two out depending on how many you have now. but you will lose some of the weight your truck can handle. but if your fronts dont have a arch left how do you have a lift?
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Offline Als87

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Re: leaf springs
« Reply #2 on: November 19, 2013, 07:34:17 pm »
Good question haha. My truck has a 4'' lift, & the front springs dont have much of an arch. I dont know how much of an arch they should have. The rear springs have plenty of arch. Thats why i was wondering if they have lost the arch over time. i dont know im just wondering why its still kinda rough.
'87 Shortbed 4x4
350, 350thd
4" suspension lift on 35's

Offline Irish_Alley

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Re: leaf springs
« Reply #3 on: November 19, 2013, 10:56:20 pm »
does it sit level?
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Offline Jason S

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Re: leaf springs
« Reply #4 on: November 20, 2013, 10:05:55 pm »
Are there just springs attached to the axles or do you have lift blocks up front? 

What kind of shocks did you go with? 

If it is an aftermarket lift kit, some have a pretty harsh ride.  Also if there are lift blocks in the rear, the rear springs are likely factory and also likely to have lost their arch. 

Can you post some photos?
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Offline Als87

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Re: leaf springs
« Reply #5 on: January 28, 2014, 11:17:50 am »
wow its been a while since i checked in here. thanks for ur replies.
yea the truck sits level.
there is lift blocks all around. i just went with gabriel shocks for now because the old ones needed replaced, i wanted to get Bilstiens but couildnt afford it at the time so maybe next bonus check.
i dnt want to lose any load capacity so i guess i will just b getting new leaf springs to see if that helps but the lift was already on the truck when i bought it so i dnt kno what kind it is or what size leafs to get. just measure em right i guess?
'87 Shortbed 4x4
350, 350thd
4" suspension lift on 35's

Offline dvdswan

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Re: leaf springs
« Reply #6 on: January 28, 2014, 12:50:09 pm »
wow its been a while since i checked in here. thanks for ur replies.
yea the truck sits level.
there is lift blocks all around. i just went with gabriel shocks for now because the old ones needed replaced, i wanted to get Bilstiens but couildnt afford it at the time so maybe next bonus check.
i dnt want to lose any load capacity so i guess i will just b getting new leaf springs to see if that helps but the lift was already on the truck when i bought it so i dnt kno what kind it is or what size leafs to get. just measure em right i guess?

please remove the blocks from the front axle and install proper lift leaf springs, you are asking for something bad to happen.

Offline Irish_Alley

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Re: leaf springs
« Reply #7 on: January 28, 2014, 10:49:47 pm »
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Als87

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Re: leaf springs
« Reply #8 on: January 29, 2014, 09:32:04 am »
Really!? I didn't kno. It was on there when I bought it. Will do nxt wknd then. What could happen? Srry for the dumb qurstion
'87 Shortbed 4x4
350, 350thd
4" suspension lift on 35's

Offline dvdswan

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Re: leaf springs
« Reply #9 on: January 29, 2014, 09:58:50 pm »
ok, lesson time... when the vehicle is driven under normal conditions, braking and turning add additional forces to the suspension.  when turning body roll is added to the suspension and creates side forces (Newton's Laws of Motion) vehicle going straight wants to continue going straight during the turn.  when braking, the weight of the vehicle continues to move forward adding extra forces to the front suspension.


now imagine those forces on this suspension, if this were the front axle those forces during turning the vehicle wants to go straight while the axle turns, something has to give, weak point is the blocks.  the forces during stopping, vehicle wants to continue going forward while the axle will stop, weak point again is the blocks.

blocks on the front suspension are illegal in most states because of this force and it creates an unsafe and uncontrollable vehicle.


Offline Greybeard

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Re: leaf springs
« Reply #10 on: January 29, 2014, 10:21:27 pm »
Quote from:  "dvdswan"
the forces during stopping, vehicle wants to continue going forward while the axle will stop, weak point again is the blocks.

Besides this, when the brakes are applied what happens? The axle housing has to stop the tires from turning. Where does that enegy go? To the block and the U-bolts. And then to the spring leaves. The leaves wrap under this torque and break catastrophically. That's bad.

So many reason's to not use blocks, they are bad enough on the rear axle but they are common and I wouldn't hesitate to use them there but all spring is soooo much better. Remember, the rear brakes don't get near the braking abuse the front ones do.
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Offline Irish_Alley

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Re: leaf springs
« Reply #11 on: January 29, 2014, 11:00:19 pm »
all of the above, your forward momentum will put your rolling weight on the front. all most like if your running and try to stop on a dime, your head will still want to move forward even though your feet are stopped and this will cause you to fall on your face. so your front axle is stopped and your truck still wants to fall on its face. now put enough leverage on the u bolts to stretch them enough to shoot the front blocks out or break. now you still have brakes but you lost steering. we have at least one member on here who lost a high school friend cause some uneducated redneck did this. when i first got into trucks i wanted to do this then i got educated, its not something that will happen 100% of the time. but who knows maybe someone pulls out in front of you and you have to do a panic brake and now your blocks break and you t bone them. i know it wont be your fault that she cut you off but it wont take away the guilt you have for taking a life when you know you could of prevented the blocks breaking in the first place. and the court will also blame you and charge you with manslaughter
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Offline Greybeard

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Re: leaf springs
« Reply #12 on: January 30, 2014, 12:16:36 am »
And then the cops will continue on and charge you driving an unsafe vehicle, and as much other phoney BS as they can muster up because you are now a depraved villain for being ignorant (ignorant is NOT an insult BTW).   ;D

Yup, leaf springs in four wheel drive serve many functions than just keeping the frame off the axles. They locate the axles on the centerline of the truck during every imaginable maneuver the truck can make, they keep the axle housing from spinning during acceleration and braking activities, they hold the truck body off the frame, they provide cushion for your kidneys, and they do all this under the adverse of conditions at any time of year. But what surprises me most is most folks don't have a clue. My wife thinks that potholes are fun.  :o  I tell her to slam her shin into the side of a coffee table at 60 mph and find out how "FUN" it really is. The first motion the tire, wheel, and axle assembly (the unsprung weight) have to do is move backwards... oh no, it can't, the spring pack is holding it. Hmmm? Then what?   
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Offline bake74

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Re: leaf springs
« Reply #13 on: January 31, 2014, 08:57:30 pm »



      I would pay, and have my popcorn ready to see this truck slam on it's brakes really hard from say 70 mph.  I only see 1 support bar, but that can not be all that truck has on it, 1 on each side ?
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Offline Greybeard

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Re: leaf springs
« Reply #14 on: February 01, 2014, 01:31:29 am »
Quote
I would pay, and have my popcorn ready to see this truck slam on it's brakes really hard from say 70 mph.  I only see 1 support bar, but that can not be all that truck has on it, 1 on each side ?

I don't see that control arm(s) doing any good with axle housing rotation.  Look at the position it's attached to on the axle. Right square on the front. Look the spring pack, it's a W shape already. Somebody has driven that truck and not just on and off a trailer. On the other hand, if there are two going to the bottom of the diff housing then it's basically just a stupid four link.  :o
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