So the infamous liquid silicone infused differential bushing gave up last year so I've been compiling parts as I've been wanting to refresh the entirety of the rear suspension. I put the G up on the QuickJack and got busy pulling the entire rear subframe. Harbor Freight lift table made removal very easy, just had to detach the handle so I could roll it under the car.


Leaves so much room for activities...


So the plan is as follows:
Subframe:
1.)Remove the rust, and undercoat to protect from any future rust issues.
2.) Insert SPL Solid Subframe Bushings, SPL Solid Differential Bushing, and Z1 Polyurethane Bushings in the front section of the differential (it doesn't need to be all solid).
3.) Replace differential cover with Z1 finned differential cover.
4.) Add Bell Raceworks Differential Brace.

Out with the old... you can see the remnants from the death of the differential bushing bleeding all down the subframe. The other bushings are in pretty good shape, only have 74,000 miles on my G. Typical rust issues around the welds, nothing too concerning.





In with the new and refurbished. I intended to do this last summer and wanted to limit the G's down time so I scored a used subframe on eBay for less than $150. The general horror stories of removing the bushings left me feeling like I could end up investing a great deal of time into just the subframe. Even with a 20 ton press the old bushings were pretty seized and I went the drill and hack method. It only took a couple hours. Then I spent a bunch of time cleaning up rust spots and used 3M Rubberized Undercoating on the subframe. The new SPL bushings went in relatively smoothly. They spent upwards of a year in the freezer (like I said I meant to tackle this last year). All in all I am happy with how it looks and it should hold up quite well for years to come.

The exhaust hanger brackets were cleaned up, hit with a rust encapsulating/preventing flat black, then top coated with VHT epoxy satin black.
I also hit rusted bolts and nuts with the wire wheel on my bench grinder, then hit the heads of the bolts with a rubberized clear coat to help keep them from corroding too much. I expect that I'll loose some as I torque the bolts, but it was a simple and inexpensive solution to keep things clean.






Rear Upper Control Arms:
Replace OEM bushings with SPL spherical bushings.
Clean up the arms and remove all the casting lines and marks. (I know nobody will ever see this but I will know it looks good.)

Rear Knuckle:
Replace all OEM bushings with SPL spherical bushings. (I have a 20 ton shop press so this is a pretty simple task with everything disassembled.)
Clean up the knuckle and remove casting lines and marks. I may spray on some clear coat to prevent corrosion.
Clean up the hub and insert Z1 50mm wheel studs.


Here is some progress:







Suspension Components:
I already have Fortune Auto Coilovers but I want to make some dampening adjustments.
SPL Rear Mid-links for added toe adjustment.
Swift Springs 7"- 65mm -10kg
SPL Rear Camber Arms
SPL Traction Arms
Upgrading my Hotchkis Sway Bar brackets to their billet brackets.

Also I'm just generally de-rusting brackets and braces then hitting them with a few coats black epoxy paint which should be durable for the underside. It wasn't too bad but the G saw a couple winters before it was relegated to fair-weather only driving.

There is probably more I am forgetting. I'll add some more pictures as I progress, I just wanted to post to motivate me to remember to take pictures and in case anyone is interested to see what will likely be unseen by most once it is all back together.

 

Great write up! It’s amazing that 4 bolts hold up the entire rear subframe but it also looks similar to my 93-300zx I did last year.

it’s a fun project if you take your time. Clean and replace along the way. I used a HF wooden dolly to drop the subframe onto it and wheeled it bavk

good luck and send pics along the way

 

And make sure you torque all suspension bolts when the suspension is weighted! (Ie wheels in the ground)

otherwise you’ll risk damaging the suspension bushings and having them fail prematurely

 

Thanks! It is one of those projects that as much as you plan for it you still underestimate the amount of work involved. I thought about going just the wooden dolly route, but I had been eyeing the lift table for a while and I had to replace the front subframe on my wife's HR-V earlier this summer and found that the lift table comes in really handy as I can roll it under and use it to support the entire subframe evenly. It also makes a nice adjustable height work bench for me.

Yep... although I don't know if that would cause quite as much of an issue with the spherical bushings.... regardless I have a set of the race ramps "restyler ramps" that allow me to put my entire car about 14" in the air and I can torque bolts as well as tune the suspension and dial in my alignment. I made a post about them a about a year ago. https://www.myg37.com/forums/car-car...ml#post4296815