Rear calipers - advice needed?
#1
Rear calipers - advice needed?
My truck has just failed it's Ministry of Transportation (MOT) test (British equivilant of the US state inspection) on poor rear brake performance. Basically, the calipers are not releasing quickly enough & the rotors are getting very hot all the time, the pads wear very quickly too + the gas mileage is awful due to the extra drag on the brakes. I have taken the calipers off & tried pushing the pistons back in & it is VERY difficult, also if I push the brake pedal they are very hard to get to come out again.
Before anyone asks I have replaced the 3 flexible hoses in case they had collapsed internally but that has made no difference, also the sliders on the bracket slide freely.
So - I have concluded that I need to buy new calipers, the truck is 12 years old with the original calipers so they haven't done too bad in my opinion. Incidentally the front ones are original too but I have had no trouble with them!
What I am basically asking is can anyone advise on a good replacement brand? I can get remanufactured USA Industries ones for around £90 each (about $60) with £25 cash back when I return the old ones. Has anyone used these calipers before or should I be looking at more expensive ones? Rockauto has several available at varying prices. I tried a GM main dealer & had a heart attack when they told me the price - around £300 each! (About $450!)
Any advice would be appreciated?
Judging from conversations I have had with some American vehicle specialists over here I get the impression that the rear brakes on these trucks are a pain in the *** - someone correct me if i'm wrong?
Before anyone asks I have replaced the 3 flexible hoses in case they had collapsed internally but that has made no difference, also the sliders on the bracket slide freely.
So - I have concluded that I need to buy new calipers, the truck is 12 years old with the original calipers so they haven't done too bad in my opinion. Incidentally the front ones are original too but I have had no trouble with them!
What I am basically asking is can anyone advise on a good replacement brand? I can get remanufactured USA Industries ones for around £90 each (about $60) with £25 cash back when I return the old ones. Has anyone used these calipers before or should I be looking at more expensive ones? Rockauto has several available at varying prices. I tried a GM main dealer & had a heart attack when they told me the price - around £300 each! (About $450!)
Any advice would be appreciated?
Judging from conversations I have had with some American vehicle specialists over here I get the impression that the rear brakes on these trucks are a pain in the *** - someone correct me if i'm wrong?
Last edited by DaveHearne; 11-15-2012 at 02:37 PM.
#2
IMO, reman'd anything can be hit and miss with the quality. I usually find the one with the best warranty and keep my fingers crossed lol. The rear brakes are no more pain than the fronts though. Just be sure to replace the copper crush washer with the new calipers and bleed the system well.
#3
Thanks man, i'm gonna take a chance on the USA Industries ones I think. Parts for Blazers are hard to come by here so if I have to order anything from overseas I get raped on the shipping costs - at least the ones I want to buy are stocked over here. They come with 12 months warranty or 12000 miles, whichever comes 1st.
Guess I have just been lucky with the front brakes then?
Guess I have just been lucky with the front brakes then?
#4
The caliper housing is aluminum, the pistons are steel, brake fluid attracts moisture, perfect combination for corrosion/rust. The boots on the guide pins crack and allow dirt/sand, moisture in, caliper brackets rust and the guide pins bind in the brackets. The hardware loses tension. The pistons rusts, the housing corrodes, then the piston binds in the bore. If you don't take care of all of the problems, you end up with what you have now
Each time the rear brakes are serviced, (rotors & pads) the entire assembly should be replaced: Buy Fenco Brake Caliper with Mounting Bracket SLC628 at Advance Auto Parts
Bolt it on and bleed it, done.
Each time the rear brakes are serviced, (rotors & pads) the entire assembly should be replaced: Buy Fenco Brake Caliper with Mounting Bracket SLC628 at Advance Auto Parts
Bolt it on and bleed it, done.
#5
Thanks for the reply Captain Hook.
I checked out those Fenco calipers & they look pretty good - only problem is Advance Autoparts don't do international shipping. However Mach5auto.com do as I have ordered from them before. Will check them out to see if they stock Fenco calipers. If I have no luck I may have to stick with the USA Industries option as they are stocked here in the UK. As I said before, overseas shipping costs are very high so it depends on price really?
Incidentally, my guide pins are fine & move freely, it's the caliper pistons that are the problem - I know what you mean about the steel/aluminium thing. I have had several Japanese motorcycles & seized fasteners are a way of life. Plenty of copper grease is the answer there.
Thanks again, will let you know how I get on?
I checked out those Fenco calipers & they look pretty good - only problem is Advance Autoparts don't do international shipping. However Mach5auto.com do as I have ordered from them before. Will check them out to see if they stock Fenco calipers. If I have no luck I may have to stick with the USA Industries option as they are stocked here in the UK. As I said before, overseas shipping costs are very high so it depends on price really?
Incidentally, my guide pins are fine & move freely, it's the caliper pistons that are the problem - I know what you mean about the steel/aluminium thing. I have had several Japanese motorcycles & seized fasteners are a way of life. Plenty of copper grease is the answer there.
Thanks again, will let you know how I get on?
Last edited by DaveHearne; 11-15-2012 at 05:23 PM.
#7
Thanks for the replies guys.
I have just got an email back from my caliper supplier over here & they have confirmed that they come with new brackets & copper washers. I just have to buy new pads. I also have to send back my old calipers/brackets to get a core refund.
I'm gonna treat the truck to a pair of new rotors as well. I have also noticed that the backing plates for the rotors/parking brakes have virtually rusted away so gonna order a pair of those too - I see that Dorman sell those. I can't remember without looking but I am imagining I will have to pull out each axle shaft to fit the backing plates? Guess it's worth the extra time to get it right otherwise the backs of the rotors are more exposed to the elements?
I have just got an email back from my caliper supplier over here & they have confirmed that they come with new brackets & copper washers. I just have to buy new pads. I also have to send back my old calipers/brackets to get a core refund.
I'm gonna treat the truck to a pair of new rotors as well. I have also noticed that the backing plates for the rotors/parking brakes have virtually rusted away so gonna order a pair of those too - I see that Dorman sell those. I can't remember without looking but I am imagining I will have to pull out each axle shaft to fit the backing plates? Guess it's worth the extra time to get it right otherwise the backs of the rotors are more exposed to the elements?
#8
Yes, to replace the dust shields you must remove the axles. It involves draining the rear diff, and pulling the seals and c clips. While you are at it, you might as well throw on new axle seals. And if you have a G80 rear end be sure to use the correct limited slip diff fluid. Its a lot of work for a dust shiled, I know several people who just let em rot off, but your call.
#9
Yes I had a feeling i'd have to take the axles out to replace the dust shields. Part of me is telling me not to bother & the other part is saying that they are there for a reason so i'm still tempted to put new ones on. I had to replace one of the bearings a couple years ago & I don't remember it being too difficult a job, if I recall correctly I had to remove a locking bolt to allow a spindle to be removed before I could take out the "C" clips to remove the shaft - seem to remember it was more time-consuming than difficult? In fact I still have the new gasket I bought for the diff as the original one stayed in one piece on the casing so I just put it back with some gasket sealant - has never leaked since.
#10
Not difficult at all, just time consuming.
When you replace the calipers: Don't leave the hydraulic line open any longer than necessary, fluid will run out. After the line is tight, and the caliper is mounted, open the bleeder and let it gravity bleed until the fluid comes out clear, (no bubbles). Then bleed as usual. If done in this manner, the ABS unit will not need to be bled. If the master cylinder is allowed to run dry at any time, you'll need an ABS capable scan tool to bleed the ABS unit.
When you replace the calipers: Don't leave the hydraulic line open any longer than necessary, fluid will run out. After the line is tight, and the caliper is mounted, open the bleeder and let it gravity bleed until the fluid comes out clear, (no bubbles). Then bleed as usual. If done in this manner, the ABS unit will not need to be bled. If the master cylinder is allowed to run dry at any time, you'll need an ABS capable scan tool to bleed the ABS unit.