Bagged My 71 Suburban

[salvo]

To read further discussion on this topic go here- LINK


I’m a total newby when it comes to air bags and IFS suspension, my other builds and vehicles are all straight axels. With all the great references and threads to be found on this Forum I tackled this project with a bit of confidence.

First off I’ll be using the Suburban for towing and hauling gear, so the drop is pretty mild compared to others that I have seen on this site. I also decided I would try this with individual shrader valves for each bag, to begin with. If I decide on an air system down the road it can be added.

Finding the parts needed took some investigating, searching, e-mails and IM’s, price was a big factor but support and communication with the supplier was just as important to me. I ended up getting most everything from a fellow Forum member way2low (Boris) He has been great to deal with and answered all my stupid questions through IM’s, I can’t thank him enough for all the help! Unfortunately as kit’s go you could have all kinds of combination of parts and no instructions with any of them. So I hope this thread may help others that are contemplating bagging there ride.

FRONT SUSPENSION
Parts!



Disassemble front end, the first unplanned bump in the road is the removal of the bump/turn stop perch on the lower arm that is attached with a series of tack welds that is in the way of the lower mounting plate. I drilled the tack welds and cold chiseled the perch off. PITA







Use the mounting plate as a template and drill holes for the mounting bolts. Do yourself a favor and buy two cobalt drill bits, one for a pilot hole the other for final size, you’ll thank me later Drilling these holes under the vehicle is another PITA I am stiff in places I did not even know I had!



Do the upper spring perch the same.



I bought a length of threaded rod, washers and nylock nuts to use for the air bag bolts, I cut the threaded rod to 1.75” ea. Bolt the air bag to the top mounting plate and bolt the plate to the upper spring perch and lower plate to the lower arm, (Do not bolt the lower plate on yet, like I did, again you’ll thank me later) also install your air fitting and length of hose you will need. I asked Boris what his shop used to seal the air fitting threads and he recommended “The Right Stuff” by Permatex for a "hopefully" leak proof install!









I looked everywhere to find an easily accessible shrader valve location, to fill the bags at, I came up with a neat location, the front and back license plate bolt holes! Had to drill them and the license plate to size. I plan to find acorn nut styled shrader caps and matching acorns for the lower license plate bolts that I added, to camouflage them even more.









I had a lot of trouble with the next step, so pay attention The lower plate needs to be drilled with one hole to anchor the bottom of the air bag to it. The best way to do this that I found and believe me I tried a few! Is an old trick I have used in the past, powdered chalk! Put a little in the threaded holes in the bottom of the air bag, shake any loose chalk out so a film of chalk is coated in the holes (We will get back to this) First make sure the bottom plate is in place only using the bolts to hold it there, do not bolt it down with the nuts! (Go ahead ask me how I know) I installed my new 2.5” drop spindle’s and raised the spindle with a jack to level the a-arms as close as possible, slide the bottom of the air bag around on the bottom plate to find the sweet spot to anchor it at, Eye ball it level, front to back and side to side. Once your happy with the location go under the truck with a small hammer and punch and tap the bottom of the bottom plate below the air bag, this will knock the powdered chalk loose leaving the exact location to drill on the plate. Now let all the air out of the bags at the shrader valve and lower you’re a-arms back down, the empty bags will be above the plate now and you should see your hole marks, you only need to anchor the center hole, I put chalk in all three just to be sure I marked it correctly. Now take your lower mounting plate off and drill it, bolt it all back together and the front bags are done!







Want Drop!





I decided I wanted anti sway bars also, CPP had a heavy Duty Front & Back kit, here is the front kit. Please pay attention again, if you do you will only need to install it once, unlike me! Since the sway bar mounts on the lower a-arms will be ¼” higher than designed since it will be setting on the lower bag plate you will need to shorten the 1” spacer to ¾” to make up the difference of lower plate thickness. Other than that you can follow the instructions that come with the kit.







Might as well install new Timken wheel bearings while you’re at it! Dang it was hard to find USA made bearings, plus they were a little less $ than the China crap all the auto parts stores are selling, really T’s me off, I get so tired pulling good old American made parts only to install China Crap! (Thanks, I feel better now)



I’ll be starting on the rear this weekend and will update this post once completed!

[salvo]

Got the rear finished, another long weekend in the garage! I was able to do all the front suspension work by myself but the rear work I needed another set of hands and enlisted a friends help, all went fairly smooth other than a few stubborn nuts & bolts. I will also need to go by the muffler shop and have the rear section hump over the axle reworked, I’m unable to get much drop without contacting the exhaust pipe!

I didn’t take a lot of pictures, it’s all pretty straight forward.
Did one side at a time, pulled the trailing arm off, replaced the trailing arm bushings, lower and upper shock perches and drilled the frame for the air bag. Removal of the old trailing arm bushing was pretty easy, the instructions called for burning them out of the sleeve, we just used a small spike/ice pick and pried the old dried up bushing out in small pieces. The upper shock perch has two rivets each that we cut off with a grinding wheel and knocked out. For the holes to mount the bag I copied the hole locations and used that as a template to punch mark the frame plate for drilling.













Mounted every thing up and ran the air line along the frame to the rear license frame. I ran the line inside some fuel line I had to protect it, especially between the area were the fuel tank is mounted since I could not anchor it in that section, it is well protected!

I also mounted the rear sway bar, not sure if I did it 100% correct or not, the instructions said that the spacer tube may need to be shortened for dropped vehicles. I took an inch off just to keep it somewhat out of the way of speed bumps, may need to buy shorter bolts and shorten it more, with the threads that were on the supplied bolts, 1” shorter was the most that would work with them. ANY BODY KNOW?







Even though I am unable to drop the rear where I want it (due to the exhaust pipe needing to be reworked) with the air bags I was able to set a stance that looks pretty good, handles like a race car and is as smooth as a Cadillac! The difference is just plain amazing! I took it on about an hour-long drive and hit the freeway too, 85 MPH it was rock solid, let go of the steering wheel straight. The steering response, ride and no body roll makes all the work more than worth it!



I’ll take another picture once I get it to the muffler shop.