I've got everything ready to remove my subframe. The only bolts left on are the rear most body mounts and the ones under the seats (they are real loose). As I started to loosen the rear most I could feel the subframe wanting to drop in the rear so I put a flat dolly under the xmember for the trans. My fear is that I don't have the body supported in the best way...I currently have a floor jack w/2x6 under the X plate thing (on verts) and two bottle jacks on a flat spot just outside of where the middle body mount bolts are.
My plan is to lift the body and pull the subframe out the front ( the fenders, skirts, bumpers etc. are all still on the car)any advice on the best way to lift the body? For that matter could I support it better than I am?
I know folks have done it, but I would not pull the sub with the fenders attached. There's too much chance of damaging the rear edge of the fenders or front edge of the doors.
The strongest place to set stands or jacks is under the rocker pinch welds up towards the front. If you have the engine out, the pinch welds can take the weight without damage. With the engine in, always place stands under the frame. The floor may bend when taking the weight, so that's not the best choice. I would put padding between the jack stand and the pinch weld. A piece of heater hose sliced lengthwise and slipped over the pinch weld would work well for that. Rubber hose will help prevent stands from slipping.
What is the extent of the restoration you plan? If you're going to take the suspension off the subframe to paint it, it's easier to take the car apart in place than to set up to handle this as a heavy assembly.
There is a great discussion by a Camaro owner about rolling the loaded subframe out from under the car on it's front wheels. It may give you some ideas.
click through the "next" button to see how he did his car.
When I assemble mine, I will probably roll the halves together with the front sub fully loaded with the engine and transmission bolted down. I'll support the back of the subframe at the transmission crossmember with a Harbor Freight transmission jack and home made fixturing. I'm not that far along, so I'm still daydreaming about exactly how this will go.
I haven't tried this, but here's an idea. Raise the car with a floor jack under the crossmember high enough to take the weight off the front tires. Set jack stands under the pinch welds close to the front and lower the car gently onto the stands. Now hook the engine crane to the subframe with chains or web straps. Balance for the subframe will be somewhere near the rear upper control arm bolts with the suspension installed. Raise the subframe with the crane enough to take the subframe weight but not the body weight. You should be able to judge when the weight is off the mounting bolts, expecially since you have them a few turns loose. Then undo the four subframe bolts. The rear half will be supported by jack stands and the front half hanging on the crane. Since the crane has wheels, you can then roll the subframe out of the way.
Here's my second idea. Hook chains to the upper fender mounting bolt holes on the wirewall. Raise the body with your engine crane while the front tires support the subframe weight. The subframe balance is pretty neutral over the front wheels with the engine, fenders and radiator core support removed.
Work safe. Place cribbing under the car to protect yourself from toppling if it shifts. Have some extra help around to balance the subframe as it comes apart.
I had my subframe completely disassembled. I rolled the subframe away from the car with a floor jack under the crossmember. The bare subframe (no suspension etc) weights under 100 pounds.
I replaced my subframe without removing the fenders, radiator support, or wheelwells. I did remove the hood, valence, and the front bumper/grill assembly. The fenders were plenty rigid and there was zero movement after the subframe was out. I removed the subframe after I had taken out the engine, trans, and front suspension.
I supported the body with two jackstands with three foot 2X4s between the stand and the floor pan. The wood was placed between the outside of the subframe and the body seam at the bottom of the rockers, parallel to the subframe. I also put a jackstand under the radiator support in case somebody decided to sit on it.
