I can sit here and think of 10 reasons that you would want to drop a k-member and only 1 why you would not, its time consuming and scary. For those of you who don’t know what a k-member is, I will give you a brief explanation along with some pictures.
The K-member is the front cross-member, which holds up the engine, and is the mounting point for the entire front suspension. It's a huge, heavy mass of stamped sheet metal that pretty much ties the front of the car together. (see figure 1)
Dropping a K-member is NOT hard technically speaking. The biggest problem is the springs, weight, and sheer bulk or it all. With everything attached, the assembly weighs in at about 200 pounds or so and is as wide as you car is. The weight itself makes this a little bit dangerous, do not try to do this project alone you will need at least a helper. My main concern safety wise is the springs. The springs in our cars, even with the car in the air and the suspension fully extended is still compressed at carries a lot of kinetic energy stored up in that spring. If it should unload at a rapid rate, it could fly out and hurt someone badly. There are two ways I know of to circumvent this problem: 1, remove the springs, and 2, chain the arms to the k-member so it cannot unload. For this article, I chose the latter option. I got this idea from my cousin Spurgeon Adkins who used this technique when dropping a k-member for my brother’s car. It's one of those “Why didn't I think of that” kind of ideas. Thanks Spurgeon.
Other than the springs and weight, there are a few things I would like to address before I get into the actual step-by-step process.
1.) The engine sits on top of the k-member so before you remove it, you must first support the engine. On cars that have a strut tower brace, it's fairly easy. For those that don't, I have some suggestions for you as well. Those with a brace, chains can be bolted to the block on each side of the engine to hold it up. Be sure to use bolts that can support the weight of the engine and use washers between the bolt and the chain so it doesn't slide through the links of the chain. Some have used motorcycle straps around the exhaust manifolds or even the entire block looping it over the strut tower brace. If you will be installing headers at this time, this is not the way to go btw. I do not recommend using an engine hoist, while it will no doubt hold up the engine, the legs go under the car where your k-member will be dropping out of the way. You don't want any kind of obstruction when doing this project. For those of you without a strut tower brace, laying some 2x4’s across the engine compartment from inner fender to inner fender will work. Those of you with garages can use some chain tied above to a rafter to support the motor. Be sure the structure is sound before doing this though. Using a floor jack on the front of the oil pan and a block of wood between them will work well also.
2.) You will need to disconnect the power steering lines and brake lines. This will leak fluid all over the place. Buy some kitty litter and spread it on the floor where the fluids spill. The last thing you need is a slippery floor when handling your dropped k-member not to mention the beating you will get from the wife. ? Don't forget to buy some brake and power steering fluid to replace the fluid you just spilled all over your floor. 2 bottles each should suffice.
3.) To chain up the a-arms you will need to drill a hole in the k-member. This will be the bolting point for one end of the chain. The other will bolt to the existing sway bar hole. Do not use any bolts weaker than grade 5, you are dealing with some serious energy in the spring so don't skimp out on grade 3 bolts. I suggest minimum 7/16 bolts and the stronger the better, again washers between the chain and the bolts/nuts. You will also need a drill and a drill bit slightly bigger than the bolt you will be using. Chain size is also important, make sure it can stand about 2000lbs of tension. The last thing you want is the chain snapping. Don't skimp.
Alright, now that that's out of the way, let's get to work. I will list down the steps in number format with notes on the side:
1. Support the engine.
Note: after you chain up the control arms, you should test your chains and bolts. Re-install the wheels and lower the car onto the ground. Remove the strut nuts, the struts are what keep the springs from unloading when the car is in the air, and raise the car again with the floor jack. If the arms don't go flying down, you should be ready to proceed with the rest of the disassembly. Put the car back on the stands and remove the wheels again.
8. Remove the brake lines at the caliper with a 14mm wrench. Tuck this out of the way.
Now you are ready to unbolt the k-member itself. Here a transmission jack would be very helpful. If you don't have that, a regular jack will do. You want to support the k-member so it doesn't fall uncontrollably. Support the k-member and undo the 2 bolts in the back and the 1 forward most bolt on the upper. Leave the rearward top bolt in as it's the easiest to get to. This will be removed after you are out from under the car. This is the part where extreme caution must me observed, you don't want 200 lbs of metal falling on any part of your body. Double check the jack and unbolt the last 2 bolts. With your helper holding onto one side of the assembly to guide it, slowly lower the jack. Be sure all wires and hoses are out of the way. It's possible the k-member will get hung up on something and not come down with the jack. Always be sure the k-member is resting on the jack. Let it all the way down. Slide the k-member out with it on a creeper or similar through the fender opening. Depending on the height of the car, you may not be able to clear the struts underneath the car. Try compressing them to clear the engine, if not remove them from the spindle completely.
Now your ready to install those new long tube headers or repair a exhaust manifold stud. You now have unlimited access to the underside of your engine. It's amazing how easily headers go in without that obstruction in the way. I suggest replacing the k-member with a tubular design. Not only is it much lighter, but you will have almost the same access with the tubular k installed as you do with it completely off. I highly recommend Griggs Racing k-members, AJE seem to be very good as well. Just remember that in the world of k-members, there are a lot of knock-offs. You get what you pay for, so don't skimp out just because it's a few bucks cheaper. This is a very important piece on your car, even more important than your engine. If your knock-off k fails, you'll be in for a hell of a ride.
Now for some installation notes. Everything goes back the same way it came off. The 2 areas that will cause some problems is the bleeding of the brakes and the re-alignment of the steering column. I will address those issues here.
Brake bleeding: After you have tightened down the lines you removed, its time to bleed the brakes. Since you most likely have drained all the fluid out of the master cylinder reservoir, re-fill it now. On the master cylinder, you will see 2 bleeder screws covered with a rubber dust cover, remove those covers. You will use these screws to bleed the air from the brake system. Using the proper sized box end wrench, loosen the up and then snug them down. They are installed pretty tight from the factory. Have your helper pump the brake pedal about ten times then have him hold the pedal all the way down. As he is holding, crack open the first bleeder valve. When there is no more fluid coming out, close the valve and have him pump again. Repeat this 3 times and move onto the next bleeder valve on the master cylinder. It's probably a good idea to lay a rag of towel on the engine so the brake fluid doesn't get on the engine. Now move onto the passenger side caliper. You will see a bleeder on the top of the caliper. Have your helper pump 10 times and hold. Open the bleeder screw and let out the fluid. Close the valve and repeat 3 times. Then move onto the drivers side and do the same. The pedal should be hard to push now. A warning on brake fluid, it will eat your paint if left on for an extended period of time. If you get any on the body of your car, be sure you wash it off with soap and water.
Steering Shaft: Make the rotors face forward. Have your helper get in the car and center the steering wheel. You can now get the steering shaft on properly. The steering wheel rotates endlessly unless hooked up to the rack. The rack is indexed to the shaft so if the steering wheel is centered and the rotors are facing forward it will be properly aligned.
I know what your saying, he makes it sound so easy right? Well it really is it's just time consuming. Total time for me to drop the k-member was 2.5 hours. For your first time allow 3-4 hours to drop it. Installation is much faster, 1 hour or so. Don't get discouraged, if you get frustrated leave and come back later. Don't ever set a time table when working on your car either, you should take it as easy as you like. If you use good safety practices and take your time there is no reason why you can't take on this task. As usual, if you have any questions feel free to e-mail me at email@example.com.
Good luck to you, see on the next article.
James W. S. Adkins