Spring Sag in '88 Suburban

'88 Suburban 1/2 ton 4x4. The springs front and rear are about 2" from the bump stops with the vehicle unloaded. Is this normal. It looks like there won't be much travel left when the truck has a full 1/2 ton of payload. Are the springs sagged? The front springs have bend up a little in the middle and the rear are nearly flat.

I've looked in the shop manual and couldn't find anything about proper spring height. Only r&r.

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

Reply to
R Clarke
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They're SHOT!!! Typical! Mine is the same way. It will be cheaper to go with an aftermarket inch all spring lift than to buy replacement OEM springs! I am putting on 4" Ranchos up front and HD 3/4T springs in back with a shackle flip...

Reply to
Shades

They're SHOT!!! Typical! Mine is the same way. It will be cheaper to go with an aftermarket 2inch all spring lift than to buy replacement OEM springs! I am putting on 4" Ranchos up front and HD 3/4T springs in back with a shackle flip...

Reply to
Shades

aftermarket 2inch all spring

and HD 3/4T springs in back with

Yeah, even JCWhitney wants $100 each for stock springs. Can the old ones be recurved?

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

Reply to
R Clarke

with an aftermarket 2inch all spring

front and HD 3/4T springs in back with

Reply to
LKN4SNO

They CAN be rearched but it isn't worth the money unless your gonna sell it soon after...the rearching usually don't last.

Reply to
Shades

soon after...the rearching

That's what I suspected. If they are already shot after 90k of mild use, I suspect they never had a good temper to begin with.

I'm not interested in extra lift, just oem ride height. I'd like to avoid any extra wear and tear on u-joints and be able to stick with stock length shocks, etc.. What if I get 3/4 ton springs instead of the original 1/2 ton? That would change the GVWR from 7000# to 7500#. That's not much of an increase in spring rate, right? Will the 3/4 ton springs bolt right on on will I need new u-bolts, shackles, etc?

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

Reply to
R Clarke

I don't think that it is as much as a 90K miles thing as it is a 17 year thing. After time they all will sag, if you have weight in the vehicle for

17 years they sag more. I think the options of re-arch, replace with stock, or replace with a lift will all cost you about the same. This is why most guys opt for the chance to go for the lift. I have seen some used ones go for free or cheap if you keep your eye out for them. If you find some used ones with less sag than yours off a truck that is getting a lift, then buy new hardware to mount them. Plan on u bolts because your odds of taking 17 year old bolts out is slim. That may be your cheapest option, or look around at trucks that have 2.5" lifts and think about that, that a pretty mild lift on a Suburban.

sell it soon after...the rearching

Reply to
Rusted

Just talked to sjared at SuspensionConnection.com to try and get an idea of how much 2" of lift from new springs would translate to lift from my sagged springs. He said my Suburban only has 1-3/4" from the bump stop stock. That's about what I'm measuring now. That's all the info I've been able to get so far. So according to him a 2" lift spring would lift just 2" from what I have now. Anyone have different info than that.? For instance if you have 2" lift springs, how far are you from the bump stop now? I'm talking an 88 Sub here.

He said his 2" lift springs would be stiffer than stock (no comparison rates) so it would move less under load too.That would help. About $700 shipped with ubolts.

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

Reply to
R Clarke

GVW is more complicated then that and the vehicle owner cannot change it no matter what he does.

Reply to
The Nolalu Barn Owl

Right. You got me. :-)

I was trying to represent relative spring rate with a single ratio that everyone would understand. Changing springs wouldn't change GVWR. There's axles, brakes, tires and a slew of other things.

What I was trying to ask was that a 3/4 ton Sub, even though it's rated for 50% more payload, doesn't neccessarily have 50% stiffer springs. All other things being equal (which they aren't), it looks like spring rate only needs to be about 10% stiffer to yield a similar suspension response at full capacity.

Since all other things aren't equal, will 3/4 ton springs produce a modest lift and more resistance to bottoming out? Will they bolt right on to a 1/2 ton '88 4x4 sub?

-RC

R.Clarke spam snipped-for-privacy@BlocKmindspring.com RTP, NC, USA

Reply to
R Clarke

Spring rate is relative to individual spring thickness(thicker=stiffer), spring length(longer=softer), and number of leafs in the pack(more leafs=stiffer).

A 2inch lift is very little and most quality shocks can handle the extra distance. Replacing the rear springs with 3/4T springs(OEM) in my opinion is one of the best things to do to a Suburban! Squishy 4-5leaf springs don't work when you conceder the amount of weight that is ALWAYS on them in a Suburban. 7+ leafs are a minimum as far as I am concerned.

Reply to
Shades

Reply to
Phantom

it's not... a 8600# 3/4 ton truck's frame is significantly stronger (thicker and taller) than a 1/2 ton frame. and Gordie *is* right.

*you* can't change the GVWR unless you're a gov't recognized upfitter.

-Bret

Look into the part numbers between a 1 and 1.5

Reply to
Bret Chase

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