JoeB's964

Well, long story short, after reading through a whole bunch of old threads and spending some quality time with Google (and even bing.com - which was surprisingly good) learning as much as I could about switching out my brake pads, I ordered up a set and sat down yesterday to tear into the job. By way of quick background, I'm not literally hopeless with mechanical stuff - I swapped out the turn signal unit on this car about a month ago when the original one busted - but I am very, VERY inexperienced working on my own car. (Which is one of the reasons I bought my 964 - what better way to learn than by doing, right?)

So anyway, the first 15 minutes of the job went flawlessly. Even I can remove a wheel easy enough, and removing the cotter pins, retaining pins, and the associated spring (the part I thought would be tricky) turned out to be a piece of cake. And so naturally, just as I start chuckling to myself about how smoothly my brake pad job was going on my first try I got stopped dead in my tracks.

I just couldn't get the %&^! pads out. In fact, I could barely get them to budge at all. I could shift them around a little - and I mean, a *little*, like barely wiggling them in place - but they definitely were not coming out. I was trying the "screwdriver through the retaining pin hole" method, and was generating enough leverage to almost start bending the screwdriver, which was as hard as I dared to lean on the thing, but neither pad would even budge.

My guess/assumption is that the piston in the caliper was still binding the pad up against the rotor, preventing me from sliding it out. Now I'm pretty sure this is a REALLY ignorant question (but I'm - you know - pretty ignorant): what do I do about that? Do I pry a feeler gauge or something down there to try and coax the piston back into the caliper and away from the pad? If so, how? Meaning, how do I get the feeler gauge/flat head screwdriver/butter knife/whatever in between the pad and the piston?

Or is this just the wrong approach; would I be better off taking the caliper off the wheel for this job and just poking the pads out from the bottom? I only tried the rears* and not the fronts - are the fronts any easier? I assume I'm way better off leaving all the brake lines & such attached even if I do remove the caliper, but are there any other traps/hurdles/gotchas to be aware of if I try to go that route?

*Well, make that "a rear" since once I got stumped I temporarily threw in the towel, reassembled the caliper with the old pads still in place, put the wheel back on, torqued the lug nuts, and went off and had a terrific drive on a flawless fall afternoon...

So the day wasn't a total loss (Hardly! How bad a day can you have when you spend two sunny hours driving around the countryside in an old 911?) but it wasn't really a clear win, either. I still have the same old brake pads that I had when I started, and while they're not in any urgent need to be swapped out, they're definitely due in the next thousand miles or so.

So, any tips? How hard should I have to pull to get those jokers out of there? Is there a trick to breaking them loose? Or is taking the caliper off (and properly putting it back on) not as hard a job as I worry it would be?

sturm

Sounds like you needed to push the pistons back into the caliper. I, Very Carefully, use channel locks and squeeze the pads back to the caliper.

'93rsa 3.8

Pesty

Perhaps the anti squeal damping pads pads are helping the pads stay in there. In that case you may need to slide something thin down there to un stick them



Removing the caliper and takig the pads out from underneath with not help beacausse the calipers have these metal liners to stop the alloy wearing and the are L shaped at the bottom.

corosion also gets behind these bending them out. this could also be restricting teh removal.

Only thing to try is get the pistons back a bit and lever them out. don't be timid with them.
If teh liners have warped getting new pads in may also be a real pain.



have a search around here I think its described

Frank 993 C4S

1) No need to remove the cotter pins. Just squeeze the spring in the middle and it will pop out at one end so you can slide out the pads

2) Don't take off the caliper as you won't be able to slide the pads out from the bottom. They are not meant to go that way and there is a metal edge that prevents from from going that way.

You need to move the pistons pack into he caliper to get the pads out. Pry a screwdriver (or two at the same time) between the pads and the discs and slowly move the pads away from the disk, one side at a time. Once you have the first pad removed, the other one will come out easier. Check out the 964 DIY section or www.p-car.com for exact instructions.

They do come out - slowly and with patience.

boxsey911

+1 on the channel locks to squeeze the pads back to the caliper. You also need them at the front to compress the cross spring that hold the pads in place (there are no retaining pins on the front calipers).

Even better than channel locks, I've found that oil filter pliers give much better leverage and because of the wide gape, allows you to put a thick piece of wood between the pliers and the body of the caliper to prevent damage:

Pesty

You say you have little experience with brakes. I have always done my own brakes and never had a problem with any car (and I go through a lot of brake parts)

the 964 brake swere a proper pain. Doable but a pain.

Here is a pic of my liners if you look carefull you can see the have warped out a little from teh side due to corrosion.

if this has happened on yours not only will it make taking teh pads out harder it will cause trouble getting new ones in.

LouZ

I believe that he has the 2-pot rears, which do have cotter pins.

I agree that you likely have anti-squeal pads, affectionately known as "mushrooms", holding the pads to the piston. Get a putty knife and slowly work it between the pad and the "mushrooms".

The other method is removing the entire caliper, but since it is the back one, it is more difficult since one bolt is only accessable thru a hole in the trailing arm using a long 10mm allen wrench. Once the caliper is off, the pad + mushroom can be popped out of the caliper. Reassembly with mushrooms involves inserting the proper size into the piston, peeling off the adhesive paper, dropping in the new pad then sticking it to the adhesive.

Most of us do not bother replacing the mushrooms for ease of future pad replacement. (most of also don't encounter squeal - YMMV).

Glad to see that you want to tackle the maintenance of your car - good for bonding! My wife wanted me to get my car just for the "fun" of doing my own repairs. I have since bought a scissors lift for my garage, and --so far--, have only had it in a shop for an alignment after I replaced the shocks and springs.

user 783003

+1 on the mushrooms. One side is adhered to the pads, the other side sticks into the piston holes. I felt like a complete dufus (or is it doofus) when I did mine. Putty knife between pad backs and mushrooms is one bit that's required. I also used a BIG flat head to pry the pads away from the rotors. Once the mushrooms are un-stuck to the pads, they will come right out.

Next question you'll have is whether to replace the mushrooms. I didn't and my brakes squeal.

Good luck.

JoeB's964

**WOW** - what an awesome resource this is! Yet another reason I'm so glad I bought this car. I post a question at four o'clock in the afternoon, and within six hours I get seven enormously helpful responses. How cool is that!?!??!

So first of all, MANY thanks to everyone for such great feedback; I will definitely try this job again this weekend and focus in a little harder to see what I can do to bust loose those mushrooms from the pads.

Second of all, follow up question about getting channel locks or other pliers in there to squeeze back the piston - how do you get the pliers to fit? With the caliper still on the wheel, I've only got a pretty small little gap (like maybe 2 or 3mm) between the pad and the rotor - so where do the jaws of the pliers go?

sturm

Don't forget the brake pad wear sensor's. They break easily and are difficult to reuse ( in my experience).

boxsey911

You need squeeze against one of the tabs on the pad backing plate (the hole the retaining pin goes through) and the body of the caliper. Protect the caliper with a piece of plywood to stop the channel locks/pliers making a mess of the paint.

JoeB's964

Got it (or at least I think I do)!! I'll give it a shot this weekend. Thanks again everyone!

Pesty

How did you get on with this, any joy?

AB-Oz

Are you going to replace the fluid and bleed the brakes? If so you'll probably need one of those mighty-vac things. I got one from Pelican and the job was a breeze. I also discarded my mushrooms when I did my pads.