I'm planning on swapping my rear end to a 4th gen rear end.

My rear control arm on one side got bent pretty bad in an accident, and the tow truck driver damaged the panhard bar. Should I put the rear end in first or should I install the control arm and panhard bar first? What is the correct order to install everything? I was thinking rear end, then control arm, then panhard bar.

From what I'm reading, the rear end can be installed at any height (preferably as high as possible for ease of installation), but the control arms should be installed with the car just lifted barely enough for the springs to stop supporting the car. Can anyone explain how to jack and support the vehicle, at each stage of the repair? I don't have a lift, I'm just using a jack and stands. I plan on leaving the jackstands under where the frame rails meet the control arms, the whole time.

I'm sure I will need an alignment after everything is done. Will having a 4th gen rear end change the recommended range for alignment settings (caster, toe, camber, thrust angle, etc)?

Also, the 4th gen rear will definitely have a different gear ratio than my current one. I can't find out exactly how to correct my speedometer. From what I've read through searching these forums, I need to replace a sensor in my transmission? Can anyone give me more details on this, like what exactly do I need to change? I just bought an ALDL cable and I'm willing to start learning how to burn chips. So if I can just correct it by burning a new chip, that would be fine too. Also how do I account for different size rims? My wheel was damaged in the accident, and I'm not sure what size wheels I'll end up having on my car.

Last question.. when I'm looking at used rear ends... is there anything to look out for besides oil leaks? Is surface rust on the axles OK or should I look for something completely rust free? I passed on a few rear ends at junkyards because they had a little too much rust for my liking. I'm thinking if I can find something on craigslist, it should have everything rust free, including the rotors and all the brake parts.

 

Rust on the housing does not mean much of anything, other than its been sitting awhile.

Pull the rear cover off.. If you have a 1/4", or 3/8" cordless impact or even a good strong cordless drill, just put a socket adapter on it and makes checking a bunch of rear ends easier/faster.

You are looking for metal shavings on the magnet on cover, metal shaving in bottom of rear, inside. Broke parts.

Turn the axles by hand, notice any free play and how much movement before ring gear turns.

Look at the teeth on the gears, see anything that looks out of place, shiny spots, a tooth or two that don't look like the rest, etc.

All of those things would be bad.

As for putting the rear end in the car.. What I do is jack up the front and put ramps under the front wheels, move to the rear, jack up and support car with stands at front of where LCA bolts up.

Ratchet strap rear end to floor jack, roll jack and rear under car, jack rear up. Put the LCAs on.. At this point no bolts gets tightened, just snugged up a tad.

Put panhard on, torque arm, driveshaft, brake lines, rear brakes (tighten rear brake parts), wheels.

Now I place a set of ramps under the rear wheels, jack still under center of rear end, jack up a tad to get stands out. Slowly let the car down onto the ramps so full weight is on the ramps.

Now tighten up all the suspension bolts.

 

The forth gen rear is a direct replacement for your car other than being wider.of course if the brakes are different use all the forth gen parts.I don't think gm painted them so good luck finding a rust free one.

 

Thanks.. Now what about alignment specs? Will the acceptable range be different because I have a 4th gen rear? Or should they be the same?

Also I'm almost certain I will be putting different size wheels & tires on the car. How can I make sure the speedometer remains correct? Also if the speedometer is incorrect, will the odometer be incorrect as well?

 

Keep in mind that the 4th gen rear is about 2.25" wider per side than the 3rd gen rear - which can cause major havoc with wheel selection to fit your car.

 

For the speedometer you will have to use some of the formulas you can find on the forum to calculate what speedo gears you will need based on tire size and the new gear ratio. There's also some online calculators that work well. The odometer will be incorrect if the speedo is incorrect.

 

The alignment will be the same.I went to the Chevy dealer and told them I needed a speedometer drive gear for a 1989 Camaro with 3.42 gears.the 1998=2002 rear end is 1.5.inches wider per side.the 1993-1997 rear end is slightly wider.

 

Thanks everyone! Now I have enough information to tackle this swap.

Where do I buy the speedo gears? I saw a site, but now I can't find it.

Yeah I know it's wider, but how would that cause havoc for wheel selection?

Let's say I kept stock wheels.. I would still need spacers for them anyway, right?

 

The 4th gen rear is wider, which if you use third gen wheels, will cause your wheel/tire package to poke way (2.25") out from under the wheel well lip. No way to use spacers or anything to fix this prob. The third gen wheels will always stick out

If you use 4th gen spec wheels on the 4th gen rear end, it will sit the wheels in the correct spot.