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How to do a 3+1 (4") AWD Lift...

77K views 261 replies 42 participants last post by  AstroWill 
#1 ·
This lift thread applies to GEN2/ GEN3 AWD vans only (96-05).

Foreword:
Before starting, I must give thanks to our Original Members and Pioneers, without whos hard work and trial-n-error, NONE of this would be possible. Corsemoto, Akforceten, AstroWill, Lumpy, CargoCrawler, Mike at JOR, Gerald at OLV and countless others... thank you for your contribution.
Special thanks to TurnNBurn, who helped me every single time I got stuck at all hours... thanks bro.

FAQ

What is a 3+1 Lift?
We are talking about 3" body lift pucks in front, plus 1" of torsion preload to get to 4" overall lift. For the rear, the standard s10 spring upgrade will be used.

Why the @#$#% would I do this?
As we all know, there are minimal suspension lift kits for these vans because they were never designed to be lifted. That being said, there are commonly 2 schools of thought to get that subframe up in the air… Body Spacers, Torsion Bar Preload, or a combination of both. Here is a side by side comparison:

Torsion Preload:
- A torsion lift (preloading springs) raises the front end by placing load on the torsion bars, using the adjustment bolts (that are actually designed for minor leveling adjustments), forcing the front end up. This reduces flexibly and travel since you are changing the starting point of those bars. This also results in decreased ride comfort for all the same reasons.
- Many lifts offer "Reindexed Torsion Keys", which allow you to preload more therefore further reducing flexibility and making it ride like crap and cause accelerated wear on the front axles. You also would need to correct the angles in the front end by flipping the upper control arms ball joints and hope for the best.

Body Spacers:
- This is a plastic or machined 3" wide puck that you place between the rubber body mount and the subframe that lifts the body up and provides additional body clearance while not affecting the ride quality or suspension travel.
- This mod requires relocation of the emergency brake cable mount (new bracket, drill existing bracket or use spacers) and trimming of the lower fan shroud since the subframe and drivetrain will now be sitting lower.

Both:
- Many kits offer both 2" body spacer pucks and reindexed torsion keys to allow you to add another 2-3 inches of lift by preloading the torsion bars.
- This method also requires modifying the upper control arm ball joints by changing the mounting position from top to bottom of the arm. This corrects the incorrect angles introduced by the torsion over-adjustment.

3+1 Lift:
- This lift uses 3" tall body spacers, (which is as tall as any sane individual would dare go) and increasing torsion bar preload to provide 1" more lift, for a total of 4".
- Adjustments of the torsion bar are not recommended for over ~1" as the front end components become misaligned. By using 3" blocks, we don't have to install reindexed keys and therefore avoid all the nastiness associated therein.
- The required mods include the same from the 2" spacer lift, (relocation of brake cable mount and trimming of the lower fan shroud) but most importantly require an extended steering coupler shaft. Without this, the 2 pc shaft will not have enough overlap to ensure reliable operation and may result in loss of steering... SO DON'T FORGET IT! The good news is that you can use the stock coupler out of any rear wheel drive (RWD) GEN2/3 Astro/ Safari as they are about 1" longer. They usually go for under $10 at your local junkyard, or an adapter can be ordered directly from Journey Off Road (JOR) for a reasonable price.

-NOTE: Since the camber and toe angles are affected, it is highly recommended you get your van aligned after significant torsion bar adjustments.

Sooooo, if 4" lift is what you are looking for, and you want that awesome factory ride, then my friend… you have come to the right place.

How Long will this take me?
Depends on your experience level. Fastest reported time so far was 5-6 hours, clocked in by GreatWhite and TurnNBurn. Longest was about 3 weeks... not mentioning any names (your secret is safe with us WinnieVan, not to fret).
Of course it all depends on how much other broken/ funky crap or rusted bolts you encounter on the way. Now that the team has done the research and test fitting, you should be able to tackle it in under 8 hours.

Do I need any special tools or skills to do this?
NOPE! Just what you see here, comfy place to work and a little muscle / patience. A strong tube bender or vice would certainly come in handy.

Is there a ton of mods required?
A few, nothing too complicated. In front, you will need to relocate your bumper to raise 3", Replace a hydroboost line, Bend trans cooler lines a bit, Drill the e-brake bracket and Install a longer steering coupler. In the back, you will only need to relocate the brake hose bracket. We will walk you through it all, not to fret.

SHOPPING LIST:
- (Qty 1) Longer steering coupler shaft from GEN2/3 RWD model (Junkyard or JOR) $10
- (Qty 2) Rear springs from S10, PN 22-687: http://www.sdtrucksprings.com/index.php ... ts_id=1430 $170
- (Qty 6) 3" Tall x 3" Wide Body Lift Blocks: Link: http://a.co/jiZvDF3 $52
- (Qty 4) M12-1.75 x 160mm class 10.9 hex head bolts: Link: http://www.metricspecialties.com/
- (Qty 2) M14-2.0 x 160mm class 10.9 hex head bolts Link: http://www.metricspecialties.com/ $30 all in plus shipping
- (Qty 3) Extended Exhaust Hangers (http://a.co/fqcue5b) $10
- (Qty 2) Extended rear shocks of your choice (90's Silverado is 2" longer but save the bushing from the old one and replace the fork type in the new shock with this one) $130
-OR-
Do the Lumpy shock mount mod... https://www.astrosafari.com/viewtopic.p ... &start=160

- (Qty 1) Extended Hydroboost Line (Master Pro PN 71817 or similar) $20 *Mods Required

Optional:
- (Qty 6) Rubber Body Mounts; Link: http://a.co/1hje2Mf (2 of the M14 mounts will have to be drilled larger, or just use your existing metal parts) $90
- (Qty 2) Bump stops
- Whenever replacing shocks, you should make sure all 4 match each other in terms of compression and return rates. Therefore, you should either match models or replace all 4. The fronts can still use the standard Astro AWD size.

Total Shopping Cost: $420

TOOLS:
Sockets: 8,10,11,12,13,15,16,17,18,19,21mm
Wrenches: 16,18,21mm
16mm crows foot or open end swivel wrench (tip: Harbor freight set doesn't have 16mm, but this does! http://www.harborfreight.com/serpentine ... 66344.html)
Vice grips
Tube bender or vice w/ wood blocks
Floor Jack w/ wood blocks as required
Tall Jack Stands

SUPPLIES:
Thread lock
Brake cleaner
WD40
Ratchet strap (opt)

JUNKYARD HARVESTING:
- When pulling the steering coupler shaft, get the rubber boot to go with it. This will save you the trouble of having to extend your existing boot. The shaft should be well greased and have almost no play when twisted. Bring a 8mm socket, 11mm wrench and pry bar.
- The rear springs from an S10 or blazer (perhaps not Trailblazer, not sure) can work, but may not give you the full 4" increase you were hoping for (like mine). You will need to disassemble the clam shells and pull the main bolts x4. Did it in about 20 minutes. Bring 21mm wrench and socket.

FRONT INSTALL:

Prep:
Remove front bumper cover and subframe, as well as diagonal supports from cover ends.

TIP: Proactively spray down all the bolts we are removing today with WD40 or similar. This will help the removal process and reduce down time screwing with rusty bolts

Trim Lower Fan Shroud:
- Remove airbox w/ 8mm socket. Remove both upper and lower fan shrouds w/ 10mm socket. The bottom is tricky, be careful I snapped mine, then later just left it out all together).



- Trim the shroud until it resembles this:



Install Steering Coupler:
- Set steering wheel to straight forward; secure with bungee down to brake pedal to allow MINOR adjustment (key to ACC position). Thanks TurnNBurn for the tip!
- Remove 2x 13mm bolts and move fuse box to gain better access to top of boot and upper knuckle.
- Remove 4x 8mm screws on upper rubber boot, and pull lower boot off gear box (metal flex ring in boot).




(Boot removed)

- Remove 2x 11mm bolts, remove coupler
- Install new coupler with boots on (you can compress them together to get to the bolts), top end first, then align to teeth on gear box. Don't let it move more than a tooth or 2 or your wheel will no longer be centered.
- Secure 2x 11mm bolts with Threadlock; secure boots.

Modify e-brake holder:
- Locate e-brake hanger bracket (near fuel filter, driver's side).


- Use vice grips or similar to secure rear cable just past the adjuster. Use 12mm wrench to loosen (add slack) to the adjuster by turning clockwise.

- Pull apart cables at this junction. Squeeze/ remove retainer clip. Remove 2x 13mm bolts and hanger.


- Drill new hole farther up approx as shown below. Might make it better than this one… oops. Set aside for now.



Modify Hydroboost Line (if Required):

NOTE: There are two types of hydroboost to pump lines for our vans. An OE version and an "new/alternate". The OE version is 41.5 inches and the "new/alternate" design is 30.5 inches.
If your van has the OE version (ACDELCO 36356390 or similar) already installed you DO NOT need to modify/replace your hydroboost to pump line while doing the 3" body lift.
If your van has the "new/alternate" design (ACDELCO 36353960 or similar) aka the one featured in this post, then you'll need to modify/replace this hose while doing the 3" body lift.
See the following two post in the comments of this thread for more information:
https://www.astrosafari.com/viewtopic.p ... 9#p1361625
https://www.astrosafari.com/viewtopic.p ... 9#p1367129

- Straighten out the (long) 90 deg bend on 18mm side as shown below. Tube bender is preferred, but I used vice (with wood blocks to prevent kinks and damage) 'cause Wimpy is always broke.
- Angle the small ~90 deg bend about ¼" more.
- Straighten the bend on the 16mm side a little as shown below.



BEFORE


AFTER

For more information and alternate method, please see this thread by MusicMan...
https://www.astrosafari.com/viewtopic.php?f=46&t=124313

Install Front Lift:
- Chock front and rear wheels or experience Darwinism first-hand.
- Remove front bumper cladding and metal sub-bumper (4x 15mm bolts)
- Bend (or install longer) cooler lines as shown below:



- Remove top 18mm fitting from hydroboost as shown below, let it dangle for now. Note: The pump side fitting is a beyoch to get to, but easier to manage post-lift.



- Remove body mount bolts x6. Front and rear are 18mm; middle are 21mm.



To lift your van off the sub frame, you can use a few different methods:

1- Lift the front end up by the cross member, then install jack stands under the sides to hold the body up. Then, use the floor jack to lower the subframe down.

2- Use a Hi-lift jack or similar as shown here by ericstg:



3- Position floor jack under front body approx as shown. If using a wood block like this, secure it to the jack to prevent tipping.



- Carefully lift body up off sub frame in small steps. Constantly check for fitment issue or tight wires/ hoses. Stop when you can fit the 3" block on top of the body isolator.
Darwin check... once lifted, use those Jack stands, blocks or what ever and don't rely on just the jack or risk proving Darwin right.
Note: If rubber is badly cracked, smushed or otherwise hosed then consider replacement.





- If pucks are not perpendicular, use ratchet straps or similar on the front of the van to pull it into alignment.
- Install new bolts through isolators and pucks. Use threadlock and torque to spec, or as hard as you can, don't be Wimpy ;)

- Lower van, marvel in what you have accomplished… but not for too long, still got crap to do man!
- Remove lower hydroboost to PS pump line fitting with 16mm crows foot wrench. The newly created gap will help a ton in getting access to this @#$%^& fitting. Note: This was by far the most difficult task on my build… one @#$% fitting. This is where the right tool and patience is required. This will also dump a pint of PS fluid, so be prepared to catch it.

- Install new modified hydroboost line, pump side first and ensure o-rings are installed or the gods will punish you. Fill reservoir, will bubble as the new line fills. May have to top off later so be advised. Make sure the new line clears the fan and pulley:


- Reinstall e-brake bracket using new hole. Pry out tangs on the insert as required to secure. Reattach front cable to adjuster as shown in previous step. Adjust e-brake cable as required to ensure brakes aren't dragging and work properly when pedal is depressed (or just slightly melancholy).



REAR INSTALL:
- Note configuration of current clam shells as shown below:



NOTE: Depending on your year, you may have to do a U-Bolt conversion. More details are pending but so far it looks like 2000+ can use the stock clamshell, older needs the U-Bolt conversion.

- Jack up rear end using common sense and as mentioned above to gain access. I also deflated tires to get more lift but also in case of catastrophic jack failure… one less thing to squish your head
- Remove clam shell nuts 2x16mm, 2x 17mm (I believe), disassemble clam shell. Note: Check condition of upper and lower rubber pads; may need to be replaced
- Lift rear end up to relieve pressure on springs. Remove 4x 21mm bolts, remove springs.

Here are the springs for comparison:





- Lift rear another ~4" to allow room for new springs. Install new springs, long side forward (~28" from bolt to centering stud). Tighten bolts with threadlock, torque to spec or as tight as you can get them.
TIP: Lay the springs on top of the axle, then slide in the front bolt first. Then, loosen the rear shackle and pivot them forward to align the rear bolt.

- Reassemble clam shell assembly loosely, don't forget rubber pads and lock/ washers. Center everything around centering studs. Run down but don't tighten nuts all the way just yet, might need to adjust things.
- Lower rear end slowly. Ensure rear axle is centered in wheel well (there is about ¼-1/2" adjustment in the clam shell), lift rear end and adjust as required.
- Apply thread lock and torque nuts to spec or just as tight as you can.
- Reposition rear brake line, bend bracket as required. NOTE: Make sure there is plenty of slack in this line to allow for suspension travel or the gods will punish you severely.

Front Torsion Bar Adjustment:
- Locate Torsion bar adjustment bolts x2 in this area:




- Turn bolts clockwise to increase preload and raise front by ~1". The amount of turns may vary, ~ 6-8 full turns.
- On a flat(ish) surface, measure between ground an wheel wells as required to ensure both sides are even and the desired height has been achieved.

Wrap Up
- Install bumper relocation brackets
WimpTech solution can be found here: https://www.astrosafari.com/viewtopic.php?f=11&t=100130
- Reinstall front bumper support or other bumper solution. Note: If reusing stock bumper cover, trimming will be required to ensure clearance with larger tires.

-GET AN ALIGNMENT!

Go over everything:
- Bolts torqued down
- Wires and hoses have proper strain relief
- Tools removed
- No extra parts/ bolts, besides the 6 body mount bolts of course

Crack open frosty beverage of choice… you did it!

For additional information and background on lifts, see AstroWill's site here:
https://sites.google.com/site/astrosafa ... safari-van

-Revised 04/09/18- Wimptech
 
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23
#4 ·
Very nice write up chris! Couldn't have said it better myself! I wish I had stumbled across this source of info when I was planning my first lift. I would have definitely started with the 3 inch blocks from the get go. Since 3 of us have now done this 3+1 its safe to say that it works with out issues. As long as you address the cooler lines and PS hose. I was able to bend the trans cooler lines without to much fuss. I did not have time to do my PS line at the time of the 3 inch puck install and it pulled my line up into the PS pump pulley. This is from the ground looking up to the pump. now I just bent it out of the way which stops it from hitting, but its still close to the pulley and is pretty stretched as it is. I will be replacing it as well when I get a chance.
 
#7 ·
Lumpy said:
Hey I'm new to the forum. I've read every post about lift kits.

I have an 03 AWD Astro. Who makes the best lift kit?

Also, I only get 18 MPG. Which kit will help me get closer to 30?

Mr New Guy
Unfortunately, as informative as this post is going to be in the future for those who want/need it. I don't think those questions are going to be going away any time soon...
 
#9 ·
Just one little change that I would make. You knew it was coming!
Jack the van up and support the body behind the subframe and under rear axle on blocks/stands. Then use the jack to lower the subframe down onto blocks once the bolts are removed.

No need for the wood block on the jack risk. Things ARE going to move because you will be moving them!
$20 worth of 2x4's to make cribbing blocks is a simple thing to do!
 
#10 ·
TurnNburn said:
Very nice write up chris! Couldn't have said it better myself! I wish I had stumbled across this source of info when I was planning my first lift.
Couldn't have done it without you man, sorry for the million questions.
Yeah me too, and like Lumpy was teasing about, I made all those stupid comments when I first showed up too. it's hard for newbies to grasp all these concepts that come easy to us that have done it.
Unfortunately, there will probably still be Mr new guy questions, but hopefully this will help shorten the learning curve.
 
#11 ·
MI_Ghost said:
Just one little change that I would make. You knew it was coming!
Jack the van up and support the body behind the subframe and under rear axle on blocks/stands. Then use the jack to lower the subframe down onto blocks once the bolts are removed.

No need for the wood block on the jack risk. Things ARE going to move because you will be moving them!
$20 worth of 2x4's to make cribbing blocks is a simple thing to do!
I was hoping we didn't need to go there like before, but you do have a good point. I added a Darwin check, thanks Barry.
 
#13 ·
Hey, nice work and glad to see you gitted her done! :thumbup:

You should give 97cargocrawler a mention, I think he found those longer exhaust hangers originally and pretty much copied his longer/bent p/s lines when I went to 3" body lift.

As the lines are so cheap, I definitely recommend replacing the p/s line and possibly even trans cooler lines when doing 3" body lift as they usually seem to start leaking at the crimp fittings once they are stressed differently from the original position. Might save some hassle and/or prevent damage/breakdown down the road. I just cut/flared my stock trans cooler lines and lengthened them with the proper tubing and good fuel injection hose clamps.
 
#17 ·
You guys gonna' be OK? What with all the back - slappin and pats n' all , thought I would get an extinguisher.
LOL
As was said... Nice work and Writeup AND Photos - Great Humor. And speaking of People always asking the same Questions:

Make this a Sticky and it might help w/ that !!

Mike
 
#19 ·
sixsix said:
...And speaking of People always asking the same Questions:

Make this a Sticky and it might help w/ that !!
Put it right below or above the other stickys about the same topic.

It won't help with the "I've read everything but somehow magically managed to not read the detailed threads with hundreds of pics".

Mr Wimp has now joined the ranks of "d00d, I'll PM you"

Lump
 
#22 ·
In the:
"Home ‹ Astro/Safari Vans ‹ Suspension ‹ Lifted Suspension"
sub-forum.

There are only (2) Sticky Threads - Neither of which pertain to "Doing a Lift".
( at least not on a "Per Thread Title" basis )
I understand that new/special shackles and leaf spring updates are part of "Lifting".
There is not One that covers a "Lift" of ANY kind in the Stickies here.

And no.. that does not let Wimpy off the hook for...
"hey Dooood, how'd you DO THAT... whooooaaa n' whattoolsdoya'thinkillneed" - PMs.

LOL

Mike

ps: Lumpy is probably correct - but those posts - Sticky or not, are not here - maybe they should be.
 
#23 ·
Agreed. I never could find any start to finish like this, which is the entire reason I did one.
As a newbie, the idea was huge and unobtainable to me, even after reading all the threads. I didn't know which was good and why so I did a ton of research and got a ton of help to finally put it all together. This is my way of paying it forward.
Besides, I may have written a work instruction/ SOP once or twice in my life, it's fun.
Read a step, do a step... get a banana
:banana:
 
#24 ·
There is no "Start to finish".

The most important thing to learn about doing a lift is that there's a lot of ways to do a lift. There isn't one "Here's how it's done". Much better if there's several "Here's how I got it done".

The frustration is multi stage -

"d00d, just tell me the ONE thing I need to know"
""There's more than just one thing. Read the threads, then ask""
"""Mean Bully! Why don't you just tell him the one thing he needs to know"""

Kind of gets old/silly/stupid/grating, pick your trait.

The more that post their versions, the better! But a thousand versions won't help those afflicted with Gratifica presto.

Lump
 
#25 ·
Lumpy said:
There is no "Start to finish".
...there is now :D ....at least for this method.

Lumpy said:
The more that post their versions, the better! But a thousand versions won't help those afflicted with Gratifica presto.
Agreed, and to them I say RTFP
 
#26 ·
Post Lift Summary:

Tires/ Rub: New tires rub...a lot....expect to do trimming on the front wheel well, especially in the back. It is mostly just sheet metal, so nothing structural until you hit spot welds. If you are not sure where it is rubbing, try spraying some flat black on the surfaces, then flex/ drive for a little and look for fresh rub marks.

Speedo: Exactly 10% off. To correct this, you will need to change the tire calibration in the ECM to correct, TECH II tool or dealer can change it for you. In the mean time, you will need to add 10% to miles traveled and speed; so when the speedo reads 50, its actually 55.

Noise: With the BFG KM2s (mud terrain), I added between 5 to 7dB to the cabin noise at 65 MPH, so around 76dB total. The howl was expected and I can still hear myself breathe, but barely.

Ground Clearance: Increased from 6.8" stock, to 11". Lower points include the front cross member and rear shock mounts.

All in, I'd say not too shabby.
 
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