Planning ahead for 3/4T 4WD Suburban suspension

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Hunter79764

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TL;DR - What's the best start for upgrading factory 3/4T 4x4 suspension to a softer riding, more comfortable setup? Budget first, Reasonable ride quality second, off-road capability needs to hold steady or get better, without a "lift".

Longer version:
I recently picked up an 87 Suburban 3/4T 4x4 (350 TBI/TH400/4.10/14 Bolt/285/75-16 All-Terrain's) that I believe is fairly stock and about 100k miles. The goal is to have a decent hunting truck that can do some reasonable off-roading, can also drive around town just fine, and have room for me, the wife, and all 5 kids when needed. It is also destined to be an RV Toad (pulled 4 wheels down behind my RV which has plenty of tow capacity etc.) for family vacations as a runaround vehicle while at the beach or state park, and otherwise be a fun truck/4th vehicle. (For the drivetrain, I've got a complete 6.0 donor truck that is a wrecked former daily driver of mine with hydroboost etc. and plan on doing that swap in the next year or so, but I think all of that will be independent of the suspension questions, aside from possibly front end height switching from 350 to LS. I will likely keep the TH400, although I may switch to 4L80 which would probably have a net zero weight impact. I've done the swap on an 85 Monte Carlo and am not afraid to dig in on the wiring and fuel system changes needed.)

That said, it rides... well, about like a 100k mile 3/4 ton truck and has springs that look... 35 years old. I'd like to start upgrading/replacing parts a little at a time to get rid of some rattles, shakes, and bumps and make the ride a little more livable. It's worth noting that I do not necessarily need the 3/4 ton load capacity, as the most towing I plan to do is a 3500lb utility trailer and/or loading reasonable day-camping gear behind the 3rd row. The rest of the truck made the deal, the fact that it was 3/4t was neither here nor there when I bought it, and a 1/2t would be facing the same suspension needs as well. I don't really want to lose any height, but I don't want to go up a whole lot, as the existing tires are nearly new BFG's and much higher will start to look like a football player on ice skates, so I'd rather not force myself into a wheel/tire upgrade right now. It handled everything I threw at it at the hunting lease this year, only scraped a little once but that was easily avoidable with a different driving line.

I am relatively new to 4x4's and off-road modifications, but I've been driving relatively stock vehicles while hunting for years. I know these bushings are fairly shot and that is the source of some knocks and rattles, and the front arches are a little bit inverted. Shocks are most likely stock and are functional, but that might be about it.
What should I start with that would be a reasonable gain without doing too much at once? I can probably put in a couple hundred at a time (remember, I've got 5 kids), and I know that it will take a while at that rate, but what should I plan on? Shocks? Replace leafs with stock height 3/4T springs? Just new bushings? 1/2T springs with a 2-3" lift? Remove some helper springs and install air bags? (I'm planning onboard air, and am also willing to manually inflate as needed for a time. Air Bags on my RV was a HUGE upgrade, so now I'm a believer). Also looking at the Jeep steering shaft upgrade, although the existing steering doesn't feel abnormally sloppy. What first, and what am I missing? Should I be looking at stock replacement, or mild upgrades from the likes of Bilstein or Rough Country? Or just fix all the soft parts before trying to mess with hard parts?
 

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Well, first, welcome to the group!
I guess first, I'd replace anything worn out.
If there's not slop in the rag joint, the Jeep shaft can absolutely wait.
I'll let others recommend springs, but you do NOT want Rough Country. They are very stiff (read: cheap). I'd be thinking a mild lift with something softer up front.
Shocks "might" be functional, but not likely after 30+ years.
A free mod to soften the ride off road at the expense of stability is to disconnect the front sway bar. (Not a good idea when its being a toad or driving at highway speeds though, IMO)
 

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Do an ORD front coil spring conversion. Post lots of pics and a detailed writeup of the process complete with before/after comparisons. If it turns out good, I will follow suit. I want to do this myself but I want a guarantee it will be worth the $$$. Oh and welcome to the site!
 

Hunter79764

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Thank for the welcome and for the advice!

ORD looks like nice stuff, but a liiiitle bit out of the budget... Good dream build material though

As for what is worn out, most of it looks worn but not worn out. The truck was actually purchased by the Texas A&M Archeology department new, and supposedly driven each semester with a load of grad students and sleeping bags to Idaho or something for their semester dig project, driven to and from the site for a week or so, then back to Texas to sit again till next semester. 2nd owner bought it around 2005 with a little less than 100k and put 15k miles on it since then as a hunting truck that gets driven to town occasionally and back to the house at the end of the season. So basically, it's got mostly unloaded highway miles, it has been maintained for the most part, and it doesn't even have a trailer hitch or wiring (I'm fixing that). So age has hit all the rubber and I'm guessing the shocks, but there's no smoking guns on trashed components.

Maybe I start with a set of shocks, then bushings? If I replace the front leafs later, am I wasting money replacing bushings in the stock springs? Is there any kind of leaf "rebuild" that would help (new pads between leafs, etc)?
I've never done leaf before (just coils), so I don't know how much work that is.

Any recommendations for the shocks?
And what about stock rubber vs polyurethane for the bushings, is there a general consensus on that?

And for reference, here's a few shots of Da Beast...
 
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Hunter79764

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Edit, maybe I don't know how to post photos? Trying again...
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Hunter79764

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Mom was gone, so I had to show the boys how to conquer a tree stump...
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Hunter79764

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Access to the rack/platform. It has spots for swivel seats, and the rail extends up to waist height as a handrail/shooting rest. There's not much in the back here, so you can see the little bit of nose-up rake I have. The front springs are probably less than an inch arched up, not sure how much is normal/correct, I assumed stock fresh would be about flat.
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Fat 454

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Hey - how did you go with the project ? Still going ? I have an early squarebody 4x4 sub that we are building. Would kill for your barn doors, ours has the tailgate but you can swap in the doors as a conversion on the early years. I'm planning to start with new body bushings/ mounts, and then to change out all the suspension bushes with poly. Decision is partly driven by the fact that LMC and others are currently sold out of the OEM rubber bushing sets. Also, poly is stiffer which is supposed to give more control ( good on street / autocross builds ). Haven't gone this way on off road before, so will be a new ( interesting ) experience, however starting with a solid base seems a good idea before going with upgrades. I am interested in the high steer / cross over steering kits from ORD tho' and looking to fit that upgrade early on. Interestingly the truck has an OEM dual front shock mount set up, however not sure that anyone thinks that was much good. May start a build thread as lots of people seem to be asking similar questions. We have hills and beach nearby, so should be able to "trail' test any changes as they are completed. PS - am planning to dissassemble the stock leaves, blast, paint and re-assemble with the poly strip in between ( ie, "re-condition" the stock suspension ). Another "cheap" conversion on the cards is to complete a rear disc conversion using OEM front discs ( truck has 8 lug 14 bolt rear end ). Billavista has some great articles if you google him ;-)
 

Hunter79764

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Didn't go far, I'm afraid... Still working on getting my shop finished, then I've got a wrecked Yukon to part out, then I'll be able to do the work on my Suburban. I've done more looking and think I'm leaning towards Tuff Country EZ ride springs up front with maybe a 2" lift (stock springs are probably sagging near that much, but I'm not sure if 2" lift on a 3/4T might actually be closer to stock height?) and most likely rebuild the stock rear springs with new strips, and possibly a small block to level it out if needed. Pretty sure I'm sold on the ORD sway bar disconnect as well, I don't think I need crossover for the height I want to be at.
But first up is going to be a full lubricate and re-seal on the driveline. I've flat-towed it about 1500 miles in the last year, and I've got drips of fluid on the T-case, front axle, and rear axle that all need a little attention, hubs need rebuilt, as well as a front driveshaft that's wobbly (bought the parts, but need to install). Once that's wrapped up, springs and shocks will be on the list for chassis work, probably after the 6.0 engine swap so that I get accurate front end height with the new engine that should be lighter than the current setup that's all cast iron...
 

eskimomann209

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Do an ORD front coil spring conversion. Post lots of pics and a detailed writeup of the process complete with before/after comparisons. If it turns out good, I will follow suit. I want to do this myself but I want a guarantee it will be worth the $$$. Oh and welcome to the site!
Best “most hilarious” comment ever.
Hey try this kit. I’d do it but don’t wanna waste my money if it’s bad… if it’s good tho. Lemme know!
 

Hunter79764

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I've also been reading up on the B52 swap for the front. I'm not sure if I want to tackle that, but it's intriguing. We'll see... I'm fairly cheap, but I like oddball stuff that works so it seems like that would be a good option for me. Depends on how much time I've got.
 

shiftpro

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The question Shawn, is how off-road capable do you want to go?
If you're going to be twisting it up (like the photo sitting on the stump... but MORE) and running larger tires then you may have to trim fenders back. We have a 'formula' where you can get a decent amount of flex but 33" tires is about the max.
Also keep in mind... larger tires means low gears in the diffs. And you're limited by the 12 bolt diffs as to strength.
 

Hunter79764

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A little flexy is honestly enough, I mostly just need hunting duty and beach cruiser for vacation etc. I've yet to really need more capability than it has stock, but more is always more better, right?
33's is fine, cutting fenders is fine (everything is bedlined and most stuff is dented up, this will never be a "nice truck" again), and with 4.10s I feel pretty comfortable for a while, but who knows?

What's the small tire flex combo?
 

77 K20

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One of the build versions of my truck was some 2" Tuff Country HD front springs, removed the sway bar, Bilstein 5100 shocks, 3" block for the rear springs. I was still towing and hauling firewood so wanted load capacity. It still rode better than it did stock. The HD front springs actually lifted 3" (as I didn't have a winch nor a big block engine to weigh it down). I'd think you would like just their "normal" 2" front springs. If you want more articulation than the short shocks provide then you can use a Ford shock tower to be able to run longer shocks and thus more articulation. (Offroad Design sells these).
The 3" block in the rear caused axle hop while out in deep snow. I had 52" rear springs that were very old- so bought some stock 3/4 ton rear springs from Rock Auto that were 56" and then bought a 2.5" shackle flip from Offroad Design. This moved my rear tire forward in the wheel well. So I needed a 1/4" axle adapter plate to move the axle back 1".
With the longer springs it rode nicer and still have load capability. More importantly I no longer have axle wrap.
 

Hunter79764

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I've already got 56" springs rear, so that helps. I forgot about a shackle flip in the rear, that might be the better option vs blocks for not much difference in price (assuming the $225 brackets have what I need, a set of blocks and new U bolts looks like about $100).

On the front, I don't have a winch but I do have a BEEFY grill guard, made out of some 5" or 6" angle iron and a bunch of 2" square tube, all of it heavy wall. Between that and the LS swap I plan, I really won't know where the front end weight is going to end up but I'm with you, I'm guessing the non-HD springs would be better suited for me. When it gets here, I'll get a front end weight and compare that with the spring dimensions and load charts to see what kind of lift I'll get on mine. I want it up a little, but not so much that the current tires make it look like a linebacker on ice skates (tires were nearly new when I bought it, 265/75-16's, ~31.5", and can't really justify replacing them right away). I love the look of the Humvee wheel/tire combo, but realistically I'd probably just go to 315's at most, maybe 305/75's. Unless I can find a couple more 16.5 rims, which makes the Humvee tires more attractive since I'm so cheap... The Super Duty shock mounts seems doable as well, I need shocks so I'll probably try to get some mounts installed and upgrade shocks at that time, which may or may not be the same time I do the rest on the front end.

Again, it's more the looks as the current worn out stock setup has done everything I "need" it to do, and there's not much rock crawling where I'm at (Dallas/Ft. Worth). Only once so far have I dragged anything, and once got stuck in sand at the beach until I had the kids jump out and lock the hubs... it's good having minions for stuff like that :)
 

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