How to remove and replace differential bushings
 

Just did this now and it works great. You need a jaw puller (I used a 4" 3-jaw puller from Advance Auto) and harbor freight ball joint press (you need this for suspension bushings anyways).

Anyways, pictures of how it all works.

You take the puller. Put a 1/2 to 3/4 adapter on it. From the ball joint tool, use the disk and 2.5" OD receiver tube.
https://www.miataturbo.net/attachmen...ine=1329193617

Heat up the area with a torch for best effect. Go slowly. Check to make sure your puller doesn't come off.
https://www.miataturbo.net/attachmen...ine=1329193617

Bushing comes out fairly easy and without any mess.
https://www.miataturbo.net/attachmen...ine=1329193617

Use a 2.5" wire brush attachment to quickly clean up the bushing bores.
https://www.miataturbo.net/attachmen...ine=1329193617
https://www.miataturbo.net/attachmen...ine=1329193617

You can press the new bushings in by hand or just use the tool. easy.
https://www.miataturbo.net/attachmen...ine=1329193617

I loaned out my HF tool and never got it back. I wish I had it when I did this last month, it looks like it went a lot smoother for you.

That's a good way to crack the diff. There is someone on here who did that and it cracked. Just sayin.

All I used was a chisel and hammer and mine out in 5min.

The key was breaking the metal ring around the bushing, you hit it right at the seem and pry it inward. That relieves all the pressure and it slides out with a few hammer taps. Drilled a few holes in the bushing too, but I found the metal ring was the key.

https://www.miataturbo.net/attachmen...ine=1329226612


see the one on the ground? notice how the edge is bent in? that's all there is to it.

But I dont reccommend those solid mounts...at least not with a cltuch LSD.

Hmm, good to know.
The worst case I could see happening is breaking a piece of the "lip" off, where the puller holds.

I'm just frustrated with the :jerkit: :jerkit: :jerkit: shops.

I used an air hammer, with a decent compressor it only takes a few minutes per bushing. No need to remove the diff from the car.

I like to use a torch/chisel on mine.

torch is silly and unnecessary.

Massive pry bar and hammer + drilling holes.

Yea that is what happened. The lip cracked. Think the guy welded it back on or something lol.

When using the torch, is there not a risk of adversely affecting the heat treatment of the alloy of the diff?

That's not what I'd be worried about. I just think the idea of a torch is silly. You can drill on the center section of the bushing easy...and a lot faster than waiting for the rubber to burn off.

Take a chisel, hit it in the sweet spot to remove the pressure, and it will hammer right out.

Yeah, I think lip cracking wouldn't render the diff unusable. But that's why you gotta slow. The bushing slides out slowly under pressure, not right away.

The torch is not to "burn the rubber" - it's to make the rubber softer so it slides out easier.

There's still the metal ring around the edge...that's what hold the bushings in so hard...it's compressed in, decompress it by forcing the metal edges away from each other, inteasd of butt-edged tightly and you're in business.

I don't burn the bushing out. I just make it more pliable, so it wants to come out easier. The whole process is about 3 minutes start to finish per side.

So you're not one of the folk here that's posted pictures of theirs sitting there blazing on fire?

LOL no. I don't understand that either. It's like my redneck neighbor who uses gas on ant hills. He thinks the gas is used so you can light the hill on fire, thus killing the ants.

I used the 3 jaw puller method on mine today. I can't imagine there being an easier way to do this job.

I honestly think I sprayed mine with PB Blaster and then hammered them out with a chunk of 2x4 and a framing hammer. In the great British tradition, reinstallation was reverse of removal.

Is this a corrosion thing for you guys?

I'm gonna try this whenever my bushings come in. I'm actually going to try it without taking the whole diff out...we'll see how goes. Thanks for the writeup, doesn't look too bad long as i have my 1,000 ft/lb impact wrench.