Rebuilding the TRs brake calipers

Ok, I spent Saturday afternoon tackling the job of rebuilding the front brake on my TR4A. I used a rebuild kit from Victoria British, it included new pads, anti-squeal shims, rotors, flex hoses, new retainer pins, all new gaskets, and some new mounting hardware for the rotor/hub assembly.

All in all the job was pretty easy and straight forward. A few things to note below.

First off, the rotor assembly on the TR4A is unique. The wheel hub mounts outboard to the brake rotor. So, in order to remove the brake rotors you have to take the hub completely off of the stub axle. Pretty easy job, only really tricky thing is getting the grease cap off the end. After that it is very easy to take the whole assembly off and then detach the rotor from the hub and replace with the new one. This allowed me to examine the wheel bearings and to add a little more grease to them. The picture below shows the stub axle after I have removed the hub assembly.



Here is a picture of the new and old brake rotors. The old rotors are quite glazed and have a lot of rust on them. Hoping the replacements help the braking a bit.



Here is one of the brake calipers after I got it off the car. You can see it is in rough shape. I ended up having to split both of them down to two halves. This allowed me a little more room to clean them up and some clearance to get the brake pistons out to replace the gaskets.



This is where it got tricky. When I tried to remove the old brake pistons only one of them would move freely. Guess this is why my braking performance has been a bit sub-par. The three that where stuck took some persuading with my handy pair of vice grips and a BFH. You can see below just what kind of shape they where in. One of the little nuances about this car is that the OEM brake pistons where made out of chrome-molly, just the kind of stuff that brake fluid loves to eat over time. So, this is what ends up happening to them. I am going to order a new set of Stainless Steel brake pistons this week. Hopefully I can get them in and on the car by next weekend.



So the TR has it's wheels back on but no front brakes on it. As soon as I can get the new pistons in it should only take a few hours to install them in the calipers, get the calipers back on the car and then bleed the whole system. Next thing on the list is to go after the rear brakes and hope they are in better shape than the fronts.

I did find out some interesting info regarding the brakes on the TR. Apparently I can swap on the front brake from an early 80's Toyota Truck to upgrade the system from a 2 piston set up to a 4 piston system. The only modifications that you have to do to the system is buy new mounting bolts and fab up a custom flex line (metric threads on one end and SAE threads on the other). The write up I read about doing this had a test that showed a 30 or so foot improvement in stopping distance from 40mph. So that has been added to the end of the to do list of the TR.

That's all for now. I am in the Mid-west this week (MO, KS, NE, IO, fun fun fun...) so I should have another car review depending on what Avis gives me this time.