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Project "Burly 'Burb"

This buildup runs in chronographic order, the earliest mods at the top and the latest mods at the end.

Our green K5 has been getting a little bit biased toward trail use, so when it came time to pick up a general purpose traveling, camping, fourwheeling truck, we ended up with this '88 Suburban.  Now that 3 kids are part of the general traveling package, the full size rear doors are great to have and the cavernous interior means we can carry all the people and gear we need, and sleep in the truck too.

The overall goal is to leave it low enough to get decent gas mileage, add a little lift and a little bigger tire to help with the offroad use, and not spend a bunch to do it.
Here's what we started with:

Here's what it looked like a day and a half later with what we're now calling the "Stage 1" buildup:

It started out with stock suspension, a fuel injected 350 motor, TH700 trans, 208 t-case, 10 bolts front and rear and 235/75 tires.  We added what is now the core of our complete 3-inch lift system (minus the steering box brace and drop pitman arm which we added later, and we use different shocks now):  Click HERE to see the current system.

3" Tuff Country EZRide front springs
Semi-custom rear springs that were left over from my K5. (stock 52" pack with 4 added leaves and no overload)
#GU38010 4" shackle flip in the rear
#GU37011 HD Greasable front shackles
#GU37012 Greasable front main eye kit
#GU38003 Greasable rear suspension bushing kit for 1 3/8" shackles
New U-bolts front and rear
#GU0010 Braided Stainless Brakeline Kit
4 new TCI-SX8000 shocks for 4" lift
#GU37001 Swaybar Disconnect Kit

We also added #BU09009 4.5" Bumpstops and a set of new 33x12.50R15 Goodyear ATS tires on 15x8 military surplus steel rims.

Total cost for the suspension upgrades was $1003.00 and the tires ran about $600 mounted and balanced. The rear springs and the wheels were left over from previous projects but neither are real high dollar items.

Then we loaded up and went to Moab for some Memorial Day ('02) fourwheeling with the family.  We ran a tiptoe through Hell's Revenge, Kane Creek, and part of Steel Bender.  The 'Burb performed quite capably, we never had to be winched or strapped, and only needed extra rocks in a couple of spots.  Not bad for a truck the size of a whale with open diffs.  And the best part was that it did it all with the AC running and got 11-12 mpg on the road trip down there. Overall pretty nice.  Here are some trail shots from that weekend:


We had a few minor tuning changes to make after running the 'Burb for a while:
The 3" front lift and 4" rear lift was intended to set the typically saggy suburban level or a bit high in the rear and measurements indicate that it sits exactly level, so a set of our Zero Rate Add a Leaves may find their way into the rear suspension in the future to make sure it stays up where it belongs.

We ran the stock steering setup for a couple months and while its function was fine, it had a small bit of bumpsteer so we added a 2" drop pitman arm and now the truck drives as good or better than it did to start with.  Part # is SKYCA50 for $95.00.

The rear driveshaft geometry worked out OK with no changes after the lift but when the truck was loaded we were picking up a vibration so before the last road trip we dropped the transfer case 3/4" and shimmed the axle up about 6 degrees to get it all lined up perfect and now it runs nice and smooth all the time.  Axle shims are #U8004 and cost $25.00 for the pair.

At this piont, (Fall '02)This truck is pretty capable as is, but since no truck is ever "done" we do have some future plans to upgrade it for on and offroad use:

Add a 4.56 geared 14 bolt FF and gear the front axle to match, in addition to adding 8 lug hubs to the front. This will make the overdrive a much more useful gear, give us better braking ability, and let us run a set of 34-35" tires that we have kicking around here.

We plan to add our bolt in steering box brace to make sure the box stays attached to the frame. This truck has a factory engine oil cooler so the box brace install will take a little more than on most trucks.

Body Protection. We need bumpers and nerf bars, no question. Proper body protection will allow us to do trails we wouldn't attempt otherwise. Or just allow us to get out of some trails with doors that still open. They might help fend off some parking lot dings too.

Locking differentials? Maybe, in the rear only. If the front gets a locker it will have to be selectable so we can still run in 4wd on snowy and icy roads.

Now for the "Stage 2" modifications

We had run some decent trails with the 'burb through the summer and used it for a few camping trips and started itching for a bit more durability and off road ability, along with some deeper axle gears so we could run our transmission in overdrive again.  So before a Thankgiving '02 trip to Moab, we decided to make some more changes.  I don't really recommend wrestling with a 14FF axle with a belly full of turkey, but it's done now.

While the 3.73 geared 28 spline Corporate 10 bolt rear had been an adequate performer for us, we were a little nervous about locking the rear up and running bigger tires.  So we started looking into a 3/4T axle swap.  What we happened to have around was a 14 bolt FF rear axle from a military CUCV truck with the standard issue Detroit Locker and 4.56 gears.  So we cut the spring perches and shock mounts off, put them on in the proper locations for a 1/2T or 3/4T truck and bolted it up.  We went the cheap and easy way on the driveshaft and used a NAPA conversion ujoint at the pinion and used our 3/4T ubolt conversion kit to bolt it up.  We also added a set of our Zero Rate Add-a-leaves to the bring the rear up a little more at the same time.

The front 10 bolt was re-geared to 4.56 and fit with 3/4T 8 lug wheel bearing hubs and rotors to match the rear. We also added the proper 3/4T caliper mounting brackets but used the original '88 calipers. We were tempted to drop in the Lock-Rite we have left over from the K5 but resisted since we know how they handle on icy roads. It'll stay open for now and be just fine.

The "new" tires are actually a set of 315/75 Procomp All Terrains on our old Stockton 16x8 steel wheels. These tires have made the rounds on several different vehicles so they're new to the 'burb and that's about it.

After this swap, we're pretty sure all subs should have come as locked 3/4T trucks.  The bigger brakes are great, it's nice not having to worry at all about the rear axle strength or durability, and the Detroit locker is almost invisible except when you want the traction.  The 4.56's work out fairly well for overall use but the motor could use a bit more power. 4.88 gears would be OK but we'll be looking into some motor mods to get the power to run in overdrive up moderate hills or with a headwind.

We did a bit of grinding on the bottom of the 14FF to smooth it up and get better ground clearance and it's definitely paid off.  More than once it's slid it's way over a rock instead of hanging up on the stock diff's lip.

The 35" tires required some more fender trimming, partly due to the size, partly due to the width of the new front axle configuration and the steel wheels. The trim job is not really obtrusive but was definitely necessary. A 1" body lift may be in the future to give them a bit more room but it definitely works now in all but the twistiest situations.

Here's a list of the parts added this time:

4.56 gear set for the 10 bolt front axle
8 lug hubs, rotors and brake backing plates
3/4-T u-bolt reversal kit
14 bolt full floating axle with 4.56's and Detroit locker
1" Zero Rate Add-A-Leaf kit

After taking us on a few winter camping trips and some snowmobile towing through the winter, it came time for a trip to Canyonlands NP for Mother's day and luckily the radiator started leaking before we left instead of after. We replaced the radiator with a new stock replacement and did a minor motor tuneup at the same time.  After adding plugs and a cap and rotor, we had a noticeable increase in power and mileage.  It's easy to forget all the regular maintenance that has to be done when we're busy doing performance upgrades, but it never goes away.

The camping trip was great, we had a comfortable vehicle to ride in on the way down, we did Elephant Hill (a 3 or 3+ rated trail) with no difficulty and drove home.  Overall the truck did just what it should do, everything we asked with no problems.

As of August '03 the 'Burb has been a daily driver for about 2 months and is doing great.  Mileage is about 13 mpg on 55-65 mph roads and it just keeps doing it's job with no major problems.  It's been on a few easier 4wd trips up here in the mountains showing off the views for the relatives and it works great for these milder trips.

OCTOBER '03 Time for a few changes.

Through a summer trade deal, we came across a set of 16x10 Weld aluminum wheels with some MT Baja Claw tires on them so we made the best of the situation and put a set of 315/75-16 BFG All Terrains on the wheels and slapped them on the 'Burb.  We've used the BFG AT's before and been extremely impressed with the overall road manners and offroad traction so they were a pretty easy choice.  The Weld wheels?  We do like them but they don't exactly fit the "budget" part of this buildup.  A set of black steel wheels would do the same job for a fraction of the cost.  Since we have them, they'll probably stay for a while.

We also had our old K5 bumper sitting around so we went mounted it up for a little rock and deer protection. The Hellas come in pretty handy too.

Here's a "beauty shot" with the new wheels and tires and the mods mentioned below.  The ride is pretty level and this is with most of a full tank and a load of camping gear.

We have been planning a return trip to the Hole in the Rock trail in SE Utah for about a year now and having been there before we knew some more changes were in order.  This is a somewhat demanding trip in that it involves a LOT of time in the truck.  You start and finish with a 6 hour drive on the asphalt, over everything from 75+ mph interstate to some slower speed twisty canyon roads.  Then you hit the dirt (and rocks) for about 90 miles of rough offroad driving with a little bit of medium grade rock crawling mixed in.  We definitely wanted premium shocks and this is where the thought process gets a bit strange.  We decided to add the standard Ford shock towers to the front to allow us to mount longer shocks but with the short suspension lift (3"), the towers would hit the floorboards, so a 1" body lift became a natural thing to add.  This also gave us a bit more tire clearance which we needed with the 35's and provided us with a good excuse to replace the body mounts with some of our urethane mounts.  Some of the factory rubber mounts were totally gone so it was really time for new mounts.

True to the nature of such processes, we just did get the body mounts and body lift installed in time to pack up and leave for the trip so instead of using the extended shock mounts, we had to bolt a set of ProComp MX6's into the factory mounts.  Luckily the shocks intended for a 4" lift worked as well as can be with the 3" springs we have on the 'Burb so it wasn't too big a deal.

This is from the lower section of the Hole in the Rock trail:



Once again, we were really happy we made these changes before the trip.  Apparently the body mounts being blown out had been creating some body creaks and groans because with the new mounts the truck is a lot quiter in twisty situations.  The 1" body lift gained the tires a bit more room and helped with clearance between all the chassis parts and the body, and last but definitely not least, the shocks....  High pressure gas shocks are the hot ticket for keeping good ride quality on rough roads and the ProComps did their job well.  The adjustment feature let us control the body roll in the more rugged sections and still turn the damping down for running over washboards, and the high pressure gas monotube design did just what it's meant to, provide quality fade-free damping despite being hammered by a heavy truck.  The shocks were hot enough to be uncomfortable to touch 3 separate times and never showed any sign of excess fade.  We've run lesser shocks in similar situations and been totally without damping after 15 minutes of run time.  We still have plans to re-mount longer shocks but even in the stock mounts, the MX6's did a good job.
 
Here's another shot from the trail, this makes me glad we didn't do this in a wagon like the guys that cut this trail out.