|When I started looking into upgrading the suspension of my 1979 camaro I spent a few days reading magazine articles, and searching the forums on Nastyz28.
Most issues were already covered, and if not, a few pointed questions soon educated me.
Compiled here are all the questions and answers you're likely to need when you're lying on your back under the car and wondering just what to do next!
What to buy?
There are several different options when it comes to replacing your sagged rear leaf springs. In order to cure the usual tail-down sag of your camaro, several people reccomended purchasing the 1980 z/28 model rear leaf springs. With 4 leafs and a bit more spring rate, the 80 z springs are available from eaton for a fair price and from NPD for even cheaper. Combined with moog 5610 or to a lesser degree 5642 front coil springs, you can achieve a pretty good rake- I've seen a few pictures of members rides with this setup and they all look slick.
Another option is to purchase the Hotchkis kit for the car, which provides a 1.5" rear drop and 2" drop front coils. Popular Hot Rodding did so for their project g/28 camaro, and so have a few other members. I ended up going with the Hotchkis kit after hearing some really good things about their customer service, so I'll be covering the one or two extra items the hotchkis springs require to be installed.
I purchased the Hotchkis kit, along with a rubber front end rebuild kit and KYB shocks from P-S-T. Since I live in Ottawa, so very close to the border, I had them ship the parts to Roethel Parcel Services in Ogdensburg NY, who'll hold your parts for a week or so for $15. If you intend to do the same, keep in mind that you still have to pay taxes at the Canadian border, so be sure to get a receipt beforehand or out of the boxes. The advantage of picking up the parts yourself is saving the "brokerage" charges that UPS will hit you with, on the order of a few hundred dollars.
First things first, you will need certain tools if you're working in your driveway. The usual assortment of 1/2" and to a lesser extent 3/8" sockets.
Before you get started, drive the gas tank empty or siphon it into some kind of container.
The first step is to jack up the car. You can lift the car by placing your jack under the diff casing (dont crimp the cover) and placing the jack stands under the rear frame rails inboard and forward of the leaf springs. With that done, I suggest you start by removing the gas tank. It sounds like a lot of work but it's really straightforward and can save you hours of knuckle busting.
First, make sure it's empty, or at least empty enough that it won't spew gas all over you when you disconnect the vent and fuel lines from the pass. side of the tank. Have a catch tray ready just in case, and perhaps a couple large bolts to plug the hoses. Next, disconnect the fuel sender wire and ground. The ground is attached to the rear bumper with a little nut. The fuel sender wire is accessible from the top through the gas door and has a plug you can separate.
The gas tank is suspended with two hanger straps. On later model 2nd gens they are hinged at the front side and bolted through the rear side. You can place a piece of wood on a jack and generally support the gas tank as you remove the bolts. If your gas tank is empty it will be surprisingly light, and the fuel filler neck will actually prevent it from dropping on your head, as well as the straps themselves, which are surprisingly strong springs. One enterprising board member even supported the tank with his legs while he loosened the bolts.
With the bolts removed, and paying close attention to the fuel filler neck so as not to damage it, slide the tank down and towards the front of the car. You will have to push against the gas tank hangers. Be sure to keep the strap pads that may come off.
Now that you have the gas tank out, this is an excellent time to look for a build sheet- which is often tucked up there. You can also take a paint stripper to the gas tank and clean things up a bit.
Unbolt the shock absorbers and remove them from the car. If they're a bit hard to get out, remember they can be compressed by hand. Wd40 on the upper bolts helps a lot- mine were rusted pretty good.
Now, loosen the bolts on the rear shackles. The lower of the two is usually fairly easy to loosen. The upper one is not! wd40 and a breaker bar along with a 6 point socket will do the trick here. If the nuts are rusted, a 17mm socket is just a touch smaller than the 11/16" they're supposed to be. If the nut is completely hopeless, then you can resort to a sawzall and/or an oxy cutter. Having attempted the sawzall approach without dropping the gas tank let me be the first to tell you that it is more trouble than it's worth. You will be picking molten rubber out of your teeth and will probably do more damage to the sawzall blades than anything else. An oxy cutter might be more successful, but I wouldn't try that without removing the gas tank first anyway!
With both nuts loosened but not removed, place a jack stand under the axle on the side you're working on. Remove the spring retaining plate nuts. These were fairly easy to remove on my car, but wd40 and a breaker bar again are the tool of choice. With the Hotchkis kit, knock the T-bolts and U bolts off the car, otherwise, leave them alone.
Support the axle and move onto the front spring perch. Try to get some oil in the frame over the bolts - it can save you a lot of time and trouble if you can get these bolts out without breaking any of the nut clips. When you inevitably do break one, simply grind or cut the head off the bolt and move on. With all 3 bolts out the spring perch should stay attached to the frame - there's a sort of notch that it tucks into until you shift the spring forward.
Remove the nuts from the rear shackles completely and place a jack stand under the spring. When you remove the two sides of the shackle the spring should drop down onto the jack stand - be careful that you don't brain yourself. If the rubber bushings give you any trouble coming out, wd40 is the trick again.
With the spring off the car, you can remove the j clips from the front perch frame. The ones with broken bolts in them may give you a little trouble- I used a dremel to cut what was left of the bolt flush to the frame, then a grinding bit to make the rectangular port the clips exit from a D shape - with the flat side towards the ground. This way, the clip can come out with a half inch of bolt sticking out the top. Both the hotchkis and eaton kits come with new clips and hardware. If you don't have them- you should be able to get some from a local hardware store.
Removing the spring perch from the springs is easy once they're off the car - place a box end wrench on one nut and when you turn the other side with a ratchet the wrench will hit the spring and hold it in place. Now that the springs are free from all the paraphernalia, it's time to toss them in the trash (or put them into the swap meet) and have a cold one.
Loki80RS writes: "hey you forgot about people with rear sway bars, it is mounted to the spring perch with the T bolts, easy enough to to unbolt from the perch but when dropping the axle it will get in the way again the easiest way to deal with it is to take it out completely undo the mounting bars from the top and it should drop to the ground out of the way, just one of the problems i ran into when replacing my leafs."
67Lemanster writes: "you might want to add that while the tank is out to replace the sock on the pick up and the rubber o ring. cheap parts that go bad after 20 yrs. looks. my sock had deteriated and kept clogging my filter."
With the Hotchkis kit your fun has just begun - the upgraded hanger hardware requires some quality time with a drill. The 8 holes on the axle have to be enlarged, as well as the 8 in the retainer plates. The plates are easiest done with a drill press and two people (one to steady the plate, the other to guide the bit and lubricate it). With light pressure the press can make quick work of the steel if you're careful to keep it well oiled. The axle retainers are much more difficult. Jack up the diff as much as you can, and if you can, have a buddy keep the steel oiled. Coming down at the holes from above doesnt really work - since brake lines and the axle tubes are in the way. Low RPM is best as well - high speed will only break things. You will need a 1/2" chuck drill and one capable of some pretty good torque. I rented a 300 dollar Ryobi drill from Home Depot for about 20 bucks and finished all the drilling I needed to do in about 3 hours. With the holes all enlarged, "finesse" the massive U bolts into place. On both sides you'll have to separate the brake line from the clip on the axle to clear the U-bolts. Now is a great time to replace the brake line if you're up for it. Resting the diff on the ground makes the bolt installation a lot easier. A 5 lb sledge helps immensely to get the larger U bolts into the retainer.
The rear shackle bushings are another fun challenge with any kit. If you're using poly bushings, be sure to grease them up liberally before installing them.. I've heard poly can squeak pretty bad otherwise. Clean out the frame where the bushings are to be installed. I used a shot of carb cleaner and a rag.
Install the metal tube into one of the bushings and press it into the frame. I HIGHLY reccomend that the first bushing you install be the side which looks to be most difficult to reach. Make sure you're using the right pair of bushings - the frame and spring bushings look identical but are different part numbers, presumably for a reason. The hotchkis instructions indicate which is which. The outside bushings on either side have a ridge in the sheetmetal above them which can be quite handy to pry against with a crowbar - so I reccomend installing the inside bushings by hand first. The first side will slide in fairly easily. The other side is VERY difficult to install. I had good luck (eventually) by prying against the sheetmetal ridge and a side of the shackle (a thick piece of steel) and forcing first the top of the bushing in, then the bottom. Once the bushing has made even a small amount of progress into the frame, you can slide the shackle bolt in and use the provided nut to press the bushing in a bit more. Once you have more space, add the shackle sides so the pressure is evenly placed over the bushings, and you're good to go.
Alternatively, if you have a rather long bolt the same diameter as the bushing hole, you can draw them in that way to begin with. Don't torque the shackle bolts yet - just install the bolts with the heads on the inside of the car (except for the top driver side bolt, which has to go in the other way since the trunk floor interferes) and loosely thread the nuts on. The lock nuts will lose grip every time they're threaded on and off.
Moving onto the springs, you have to re-use your old spring perch, so now is a great time to clean it up a bit. Make sure you know which one goes on which side. Torquing, removing and retorquing these is not fun (don't ask me how I know). Place the spring on the ground beside the car as if it were already installed, with the arch down and the eye at the front. Place the perch on the car to make it's not upside down or on the wrong side of the car, then place it onto the spring and install the bolt with the head on the OUTSIDE of the car. For some reason my Haynes manual said to place it on the inside, but if you do so the length of the bolt will hit the floor as you bolt it up... so it doesn't work. If you like to be exact, you can torque the bolt on the perch down to 70 ft/lbs while it's on the ground, but this will make installing the perch more difficult - especially if it isn't level with the floor of the car. After doing one spring each way, I reccomend getting the bolt near tight, and then torquing by hand with two wrenches (ratchet won't fit) as tight as you can when it's on the car.
To install the spring, place the poly bushings in the rear eye (with plenty of grease) and make sure you're using the right pair of bushings - the frame and spring bushings look identical but are different part numbers, presumably for a reason. Heft the spring up to the rear shackle and pass a bolt through the bushings and shackles. At this point it is a good idea to lift the axle and place it on stands - it's much easier to install the spring without hulking out as you bench the spring and axle up with one arm. Placing the three J clips into the frame make sure you have the bolts close at hand. Jack up the spring if you have to, and try to get the three holes in the spring perch lined up with the three in the frame. The furthest front is the easiest to start with. To get the other two to line up it helps to have a long thin screwdriver to lever through the holes.
With the rear up and front perch in place, put the leaf pad on top of the leaf pack and drop the axle on top of the spring.
Find your spring retainer plates. On the pass. side the shock mount is forward of the axle and curved edge should curve down. On the driver side the shock mount is rear of the axle but the curved edge still goes down.
Place the leaf pad on the retainer, slide the retainer up on the U bolts, and run the nuts up a bit.
Lather rinse and repeat for the other side, then place the car on the ground- give it a bounce- and torque up all the bolts. The front spring eye should be about 70 ft/lbs which you probably won't be able to exceed using simple wrenches, I don't care HOW strong you are. Do them up as tight as you can. The rear shackles should be 50 ft/lbs. The spring-axle retainers should be 40 ft/lbs according to oem although with the upgraded hardware you basically just run the nuts up until they're snug and the retainer is touching the axle.
Lift the car back up and support it by the frame rails to install the shock absorbers. The upper bolts are 5/16" if your kit doesnt provide any new ones.
If you want, now is the time to clean up the gas tank topside and even inside. Wire wheel, grease remover and rust paint are my weapons of choice. Nobody will EVER see the topside of the tank so do what you like. Place the tank on a jack, roll it under the car til the back of the tank is pushing against the straps, lift the neck up into the hole and lift the tank into place. Be sure you get the hanger cushions back on the tank. Once the tank is up, wiggle it around til it looks like it's in the right spot, press the straps down as much as you can and start the bolts. Reconnect the sender wire and ground, lower the car back onto the ground and admire your handiwork.
Triple check you have no "Extra" parts lying around and take it for a spin - then double check all the nuts and bolts.
Enjoy the ride!I hope this guide helps anyone looking into replacing their springs on their driveway. There are a lot of instructions out there that are vague and worst of all, simply tell you what to do and not how to do it. I have next to no experience and it only took me a couple weeks... perhaps 50 hours of novice time. If I'd had this guide when I started out I would have been done a week sooner!! Lots of thanks to everybody who answered my stupid questions on the nastyz28 forum!
Author: MadMike Maciolek
North Georgia Classic Camaro
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