Differential Bush removal options
 

Hi guys. New to this forum. Already read into some helpful DIYs for the diff bush mod for our Z cars as mine blew months ago. I'm actually surprised it's still running decent with a loose diff bush. Probably not a good idea hah!

My question is simple. Is there any other way to take out the OEM bush without using a hacksaw? Just concerned if I cut too deep into the subframe I'll damage it if not careful. I'm new to the whole DIY mechanics stuff so any helpful info is appreciated.

You could try Z1's removal tool. But it's a piece of chit.

If you are installing a SPL bushing. Put it in the freezer for a couple of days. Or pack it in dry ice. If you are installing a poly bushing. They like to squeeze out at the sides when being pulled in. The bushing hole is not perfectly round. It's kind like egg shaped. It got that way from the welding.

The oem bushing has 2 chambers with silicone fluid. The one that's leaking, you don't have to worry about. The one that ain't leaking will spray fluid about 3 ft when you start to cut in to it.

Once you have the diff out. Work from the front of the bushing. Use a 1/2' drill that you plug in. You could smoke a cordless drill. Cut out the inner bushing using a 2" hole saw. I linked it below. Then using a sawzall. Make 2 or 3 cuts in the outer shell. One at the bottom of the shell. The other ones at the 4 or 6 o:clock positions. Being careful of not going too deep. Stop and inspect your cuts a couple of times. Once you have your cuts done. Use a muffler tool. Link below. Position the cutting edge of the tool with one of your sawzall cuts. You can hammer it out, or use an air chisel and you will be done faster.

Once the outer shell is out. Use a 2", 40 grit flapper wheel on a drill or die grinder to remove the paint and smooth out the inside of the hole. Link below. MAKE SURE THAT THE INSIDE OF THE HOLE IS BABY BUTT SMOOTH! If you have any burrs or metal sticking up. You will not be able the fully install the bushing. As it will hang up on the burrs. And you are SCREWED! Once you have the hole cleaned up. Anti seize the chit out of that hole. Install the bushing from the front. You will have more working room.

To install the bushing. I used a piece of 1/2" threaded rod about 14" long. Double nut the one end of it. 2 pieces of 3/8' thick, 4x4" squares with a 1/2" hole in the center of them. On the thread rod, put a couple of 1/2" washes on it and slide them back the the double nuts. Take one of the plates and position it on the rear of the hole. Then put the threaded rod through it. Put you bushing on the rod, followed by the 2nd plate, a couple of washers and a nut. Finger tighten the nut up. Make sure the bushing is squared up with the hole before tightening the nut up with wrenches. Once squared up, start to tighten the nut. Once you can't turn the wrenches anymore. Use a hammer and beat on the plate. You will have to repeat this a few times. Once you have the bushing flush with the hole. Remove the plate and put a big socket on the rod, followed by the plate. You want the bushing about 1/8" to3/16" below the front of the hole. If you don't get the bushing far enough in the hole. You will have trouble installing the front 2 bolts.

Use this hole saw. It cuts deeper then any hole saws.
https://www.homedepot.com/p/DIABLO-2...00CT/301697691

Muffler inner pipe cutting tool.
https://shop.advanceautoparts.com/p/...B&gclsrc=aw.ds

Flapper wheel
https://www.premiumtool.com/flap-wheels/

Good luck on your install. :tup: I've done a few of them. :icon14:

Thanks! Didn't expect all that info overload! Appreciate it. I have the whiteline diff bush set. Guess I have some tool shopping to do heh.

Also could I just get away with having the bush flush on the rear side? The DIY pics seems to have it that way and it works fine for them. Also you mentioned anti-seize. What product would you recommend? I'm from Australia so brand name might be different. It wouldn't happen to be WD-40? Actually the whiteline set comes with a lubricant satchet. Not sure if that's what you mean.

This is the most outer bushing you’ll be cutting to get out; it’s like the oem glues it in place. :tiphat:
Here’s pic of the anti-seize too :tup:

Haha cool appreciate the pics. Atleast I have an idea what to get now. Should hopefully make this mod easier to do.

One more pic of the hole in subframe, after bushing is out.
As as Rusty has given you professional instructions on removal & installation...it will come out in multiple pieces :ugh2:

Finally got that dang stubborn old diff bush out. But I made a mistake though. I sort of cut past the outer shell a little bit. I hope this isn't too bad of a mess up?

I didn't realize how stubborn that outer shell was. I thought after you cut the metal it would just naturally break apart and come out. But after I hammered it out a few times it started to lift and come out.

Sorry about the pic. My phone won't focus properly. It's the scratches at the top mid left.

You HAVE to smooth all of that out with a flapper wheel. It's got to be baby butt smooth. Otherwise, suicide will be on your mind.

Thanks man. Appreciate your helpful advice and tips.

:tiphat:

Where did you source the flapper wheel? The link is to a Canadian company that doesn't have online store nor have they answered my email for 2 weeks. I haven't been able to locate one through online search. :tiphat:

Home Depot. :tiphat:

https://www.homedepot.com/p/WALTER-S...F306/305936869

Nice thanks!! Been searching flapper wheel all this time and dang HD etc. didn't make the relation. :shakes head:

You have watch your search on Home Depot. You put in flapper wheel, and you get toilet flappers. :icon14:

Pretty much. I noticed the same with ebay, amazon and lowes as well with Amazon ALYAWS being a fail! So much for AWS. :rolleyes:

Hi ya Rusty,

Wouldn't the Anti-seize be detrimental to even polyurethane? I'm assuming Whiteline and SPL are both poly.

Are you worried about corrosion in the subframe or for eas of install as a lubricant?

Either way, I think White Lithium grease would be safer on the poly and still provide anti-rust properties.

zz

The SPL bushing is solid aluminum. The Whiteline is poly. I haven't seen any reports of anti-seize being bad on poly. I use the anti-seize for installation of the bushings. I know you won't get far trying to install a bushing dry.

Rubber or poly, may want to use dielectric grease...but as Rusty states, haven’t seen issues with anti-seize compound on rubber. :ugh2:

Right. Forgot SPL is solid Al. I would definitely use anti-seize.

I agree, you have to use something. Even Butter, if that's all you got.:rofl2:

:tup:

After having done a few bushings. I would rather do solid bushings then poly bushings. The poly bushings like to squeeze out in the middle when pressing them in.

Are you talking just the diff or all around on suspension where rubber exists?

So my understanding with solid bushings, you will feel and hear the vibrations more pronounced? What's you experience?

zz

The aftermarket poly diff bushings likes to squeeze out.

I really don't notice that much difference with the solid diff bushings until I installed the solid sub-frame bushings. With the rest of the SPL suspension bushings. You pick up a little bit of noise. (I have earing aids) But the suspension works so much better.

Just a heads up for those searching for flapper wheels - they are readily available from Amazon. Lots and lots of vendors. Search for "flap wheels" or "flap wheel sander".

I got a 12 pack of different grits for just over $15. Worth every single penny. And a HUGE thank you to Rusty for this advice in the first instance. After using the flapper wheels (I went through 2), and a decent amount of anti-seize, my solid SPL bushing went in super easy.

Ok so removal complete and Whiteline bushing in.

1. Used the 2" hole saw but started running into the center boss of the OE bushing. I was probably on an angle due to the size of my drill. Punched through a few times with a screwdriver and it came out no problem.

2. Instead of cutting all the way through the outer portion of the OE metal portion of the bushing I did one full depth cut to the subframe bore nd another partial. I then banged a screw driver between the subframe bore and outer portion of the OE bushing which folded making a tab. I was them able to use a screwdriver to collapse (pull in making the diameter smaller) the outer portion and pull out by hand. Think about how a snap ring works, same idea.

3. Used the flap wheel which worked amazing to smooth the subframe bore.

4. Lubed the bore and whiteline bushing with anti-seize and pressed in with an 8 Ton bottle jack from HFT which I already had on hand. It fits perfectly between the bushing and forward section of the subframe. I orientated the base at the bushing and ram toward the subframe. Less than 1 minute to push it in, zero bulging and other wise no drama. I tapped it with an 8 lb. hammer until the front of the bushing was even with the subframe bore. If it needs adjustment it will be easily pulled by the nut connecting it to the differential cover after the front two bolts are in for static orientation.

Thanks to Rusty for the heads up on the deep hole saw and flap wheel.

What a mess using the hole saw which required lube as to not stall my 120V Dewalt drill. Had to stop on several occasions to let the drill cool off as well as the OE bushing as when the rubber heats up, even with lube it begins to grab, stall down the drill and make tons of nasty rubber smelling smoke due to the friction.

My 120v Milwaukee 1/2" Magnum Hole Shooter chews right through the bushing. :D

Did the bushing squirt at you when you started to cut? :rofl2:

I think part of the problem was the angle my drill was out due to working room. It was starting to cut into the center metal bolt hole. :icon14:

No I heeded the advice to drill the bushing before doing any hole sawing. I put rags over the area as well.

Interestingly enough fluid came out of both sections even though I had dried and burnt fluid on the driver side exhaust. No huge staining down the cover like pictures I'd seen though. Even through I have a cover brace the whiteline's further solidified upshift and downshift action so it was worth all the effort. :tup:

Anti-seize = lubricant. For urethane or polyurethane use silicone grease.

Freezing and grease will make the install go smoothly and if need be disassembly if you screw it up.

Just completed this R&R project. My two cents:
1. I used the puller tool from Z1. It is heavy-duty and well designed...but damn that OEM bushing is stubborn! I was using a 20" breaker bar, pushing it with my leg since I lack the upper body strength to develop enough torque. It took me over an hour just to remove the outer race of the OEM bushing. I would push the breaker bar about 30 degrees with my leg then a friend would reposition the socket and I'd push again. Repeat a billion times. Eventually, though the bushing came out. Total tortoise and the hare situation.
2. Rusty is a god for suggesting the flapper wheel. Easy peasy, with awesome results.
3. New Whiteline bushing went in easily using the Z1 tool. Was able to get it in simply with my ratchet wrench. Note that the Whiteline bushing comes with its own lubricant (I think it's silicone). So no need to stress about what kind of "anti-seize" stuff to purchase.
4. I did find that the connectors on the two sensor wires on the diff were going to be a bit balky, and even after disconnecting them you would still have to pry the wire off the frame at two points. I found it was much, much easier to simply pull out the sensors where they meet the diff. Each is held in by one cap bolt. Simple to pull those bolts and remove the sensors, leaving all the wiring in place on the frame.
5. Don't forget to buy a new exhaust gasket for reinstallation of the exhaust assembly.
Cheers!