6G Celicas Forums

Hey folks,

So when I last took my GT-Four to get my new wheels (to a performance garage), the mechanic told me one of my front calipers was seized, and my rotors were not in the best condition (pads looked new though).

I've gone ahead and bought replacement rotors and received my caliper rebuild set in the mail today, but I'm not quite sure whether this is a task I should do on my own with my limited mechanical experience, especially working on something critical like the brakes.

I've phoned the garage, and they've quoted me 4~5hrs of labour.

I've also looked around the web to see some FAQs and have found these two DIYs:
GT4dc.co.uk
GT4OC.net

Now the question comes to this, should I save myself $350 in cash and attempt this on my own, or get it professionally done?

The part I'm most unsure about (since I've never done it before) is working with the brake-line (bleeding and such).
What will be the most difficult & critical part if I decide to do this task myself in my own garage?

This post has been edited by Jeebus: Feb 13, 2014 - 2:31 PM

It isnt too difficult of a process.

If you are doing a full seal rebuild, you need to remove the pistons, which you will need an air compressor to do.

Bleeding the brakes, with stock bleeders is a 2 man job. Id suggest getting speeder bleeder fittings to replace the stock ones. It makes the bleeding a one man job and cuts down on your bleeding time. That coupled with a vacuum pump bleeder from Harbor Freight, and bleeding takes a second!

If you can go without the car for a bit, and you have the tools to do it. Do it!

you don't need an air compressor to remove the pistons!
I used 2 screw drivers and just popped them right out.

Unfortunately no HF in Canadia. I'll go check out Canadian Tire or Lordco for some fittings, and YouTube for a lookup on makeshift vacuum pumps. I think I may purchase 4 new pistons as well since I dont know the condition of my current set.

you could ruin the pistons!! RUIN I SAY!!!!! RUUUIIIINN!!!


If you get new pistons then Id go with playr's method.

Seems like you are ready for the job!

Looking at those links, what would make a piston unusable? If there is a little surface rust, ive read on some other sites that Iyou may be able to use a high-grit sandpaper to rid of it and re-use it.

If they are rusty, replace them. Sanding them wont last for long and you'll probably end up with some leaks. Rebuilding the calipers is an easy do-it-yourself job. Worst part will probably be the removal of the pins that holds the pads in place.

This post has been edited by nsxtypeR: Jan 25, 2014 - 10:51 AM

You could ruin. But take your time, blue tape the screw driver and use lube...should be OK.

Quick question:

I just discovered that I already have stainless steel braided brake lines installed. I'm not sure whether this is another TRD option that was stock on my car, or if the previous owner installed it, but I was under the assumption that I had plain ol rubber lines from reading other GT4 owners that upgraded to SS braided lines.

When I remove my front calipers to rebuild them, what should I do with the brake lines? I was under the assumption that my lines were rubber, so I had some locking pliers on stand-by, but ... now what? Just let them hang and drip all over the place while I rebuild my calipers?

Also, after I remove the rear calipers, am I going to have to mess with my ebrake at all when replacing just the rotors?

This post has been edited by Jeebus: Feb 11, 2014 - 1:04 AM

I usually take the lines and stick them in bottles i might have laying around. At least that way they wont drip everywhere...

bottle the lines. ^

Brake fluid is super corrosive and you dont want that stuff getting on anything.

You shouldn't have to mess with the ebrake at all. Just make sure that the e-brake is disengaged when you take the rotor off. On some occasions the rotor may not come off and could be stuck to the E-Brake Pads, in that case, there are screw holes on the face of the rotor where a bolt (i forget which one) can be threaded in to push off of the hub behind the rotor which will push the rotor outwards.

There are some other possible issues that might come up but its early and Im sick of typing right now! haha

I have always opted to buy remanufactured calipers rather than try to rebuild myself.
For the most part you just un bolt the caliper and putt new one on. Then get a friend to help you bleed it.
But watch a couple bids on bleeding it, if you mess that up you could be in big trouble.

Also you generally need to flush the old fluid all the way through if it looks old and dirty, bad fluid is what causes caliper failure in the first place.
You just keep putting more fluid in and bleeding it out, until the new stuff is squirting out the hose.
But you would need to bleed all four wheels, starting with the longest brake line.
Also be sure and regrease the slider pins with some bearing grease

Or you may not even need a caliper.
Take a little strip of wood and a C clamp and try to slowly push the piston in, if it will go all the way back in then it's just fine.
It may be that it's dragging just because the slider pin is seized cause the grease is gone.

This post has been edited by VavAlephVav: Feb 11, 2014 - 11:09 AM

I'm thinking reman GT4 calipers are rather pricey and a rebuild (seals) is pretty easy.
GT4 calipers also do not have a slider pin like the USDM brakes do.

I found this out as I finally took my one caliper off. I now have a can of silicone spray that I probably won't use anymore.

Status update, it took me 5hrs of labour to do my front left caliper from start to finish..... Haha. Mind you, I'm working in my dad's garage for the first time as they just moved into a new home in Dec. I didn't know where anything was, or what tools I had available, plus doing this for the first time. I thought this project was going to be a son & father afternoon, but he had other plans and left me.

Biggest challenge for myself was getting all 4 pistons out while being as clean as I could, and bleeding the brake. It's dark now and I'm working in a cold garage. I'm trying to decide whether I should do the other caliper now, or replace the rear rotors under a floodlight, or whether just to hold off until tomorrow.

I'm trying to take pics, but my hands are getting covered in brake fluid (no plastic gloves), so I'm trying to limit using my camera. I'm sure there's enough pics on this whole subject though.

I should of known that the gt4 would have some performance calipers. but so then does it use pistons pushing from both sides? I guess I have seen the racing style ones with 4 pistons.
also, do we have a thread on how-to rebuild calipers? even regular ones?

and you would want to use something like a bearing grease for the slider pins anyway, the silicone spray breaks down at a lower temp and could lock up
if the brakes get really hot from hard use or dragging. but I guess you don't have to worry about that anyway

but that silicone spray stuff is great for things like door/hood/hatch hinges, door latches and anything else that gets squeaky

I would take all the calipers off and rebuild them one by one. (and have the fluid partially drain into bottles) and then hook them all up and fill & bleed.
Rotors take a couple seconds to swap (if the old ones arent stuck)


I dont believe there is a how-to rebuild thread for the ST205 calipers. There is a thread to most all the part numbers to rebuild them though (short of piston part #'s)

I've had to search high and low on rotor replacement and caliper rebuilding. My original post has the two threads that I originally read and decided to do this on my own. I also watched a bunch of YouTube (Eric the Car Guy's) vids for additional info. I wish I took more pics along the way, as I'd write my own DIY, but didn't really thing of it.

My next problem is this: My first rotor (Front left) came off no problem, and my other 3 rotors are rusted on. I was able to remove the front right, but the garage is too dark for me to rebuild the caliper at the moment, so I moved onto the rear rotors. I attempted to remove my rear left rotor, which was rusted, so I banged on it with a mallot to get it loose. But now, it seems to be catching on something that I cannot pull it off. I'm afraid that it may have something to do with my ebrake which is fully disengaged in the car. Is there anything I need to do in order, such as adjust something in the ebrake adjustment hole on the rear rotors to be able to pull it off, or should it just simply slide off?

According to this site, the rear rotor should simply come off, but it isn't going so smoothly for me.

lol. to remove the rear rotor, granted the e brake is not applied.

just simply insert two screws on the threaded holes you see near the hub, do this evenly. and it will come out..

I'm going to try this right now, but I've also finally found some threads on adjusting the e-brake shoes via the adjuster behind the rotor. Perhaps the shoes are catching on the rear of the rotors.

Some links to help:

This is what it looks behind the rear rotors (disc brakes, with drum e-brakes, as per my GT-Four). This is not a picture of my own rotors, but one I found through my searching. The shoe adjustment dial is the horizontal silver cylinder with the notches in the center at the bottom of the assembly:

Help 1
Help 2
Help 3
Help 4
Help 5

Update:
I couldn't find any screws to fit through the threaded holes, so I adjusted the parking brake shoes. I took this shot after I loosened the parking brake and the rotor finally came off. It was a good thing that I didn't keep on banging on the rotor with the mallet as I could've done some damage to the shoes. I did the instructed steps (when rotor was still attached) of tightening the adjustment until I could no longer tighten it, then loosen it by 8 clicks.


Almost done my repairs!

This post has been edited by Jeebus: Feb 12, 2014 - 2:37 AM

ya ive found that once you adjust the cable inside, it messes with the wheels, then you adjust the dial at the wheel so its not dragging and then the handle seems
to pull up way too many clicks. im not sure on the right way to set it up and its been way too cold for me to dick wit rtm