front caliper pins

[Lv1G6He3V2]

I'm painting my rotors (not the braking surface) and calipers.

 

The rears were easy, just very time-consuming prep, but we couldn't get either of the front caliper pins out. I know only one has to be removed, but I couldn't budge either of them. My friend cut his arm trying to break them loose when the T55 socket bit tip twisted - so much for the bits being hardened steel! He said the shop must've put the pins in with an impact wrench.

 

Why the ^%$&*#%* did GM use torx heads?

 

When I do get them loose are there replacement pins with normal hex heads on them?

 

'99 Sierra 1500 GMT-800 RWD

[iminaquagmire]

Have you tried heating the caliper bracket/pins? Some heat and persuasion with a good bit and breaker bar should get them off. The extra leverage of a longer handle helps immensely. Also a mix of 50/50 ATF and mineral spirits soaked in a few hours before you try would help. Or any real penetrating lubricant (not WD-40) but I like the ATF mix.

 

I don't know about replacement pins. I've only ever seen the T-55 ones. The problem other than having the T-55 socket is that the threads are on the end and a smaller surface area. Its easier for it to get locked in there. Some Anti-seize will protect the threads when you put them back. The GMT-900 is a different design entirely but at least that has a normal 18mm bolt holding the pins in. If you needed new rotors and calipers you could swap to the GMT-900 ones as long as you have 17" wheels or bigger. Its a pretty popular cheap mod for the GMT-800 platform.

 

Also, you can paint the braking surface as much as you would to not have to tape. The pads will scrub it off in short order making a clean line.

[davidsi21]

You might try Kroil brand penetrating oil. Its a little more expensive than PB or WD40 but it works wonders.

[MI 99XPL]

I'm not sure how to get those suckers lose, but here's an idea if you can't find a hex style replacement slide bolt.

 

After you figure out how to remove the bolt, weld on a nut to the top of the T-55 head. Just pick one that is the same size or smaller as the head. It'll clear the wheel since the slide bolts points toward the engine bay. Keep the weld on the inside of the nut. If you have to weld on the outside, you might need to grind off some of the weld to match the profile of the nut.

 

Sounds crazy, I know. But I've use that trick when I had my 1st vehicle that used metric sizes and I stripped the head of a bolt. All the stores were closed and I need the car 1st thing in the morning. Beleive it or not, it was easier to turn the bolt with the welded on nut than the bolt's mate that I didn't weld a nut on when I had to work on it again.

 

Good luck!

[Lv1G6He3V2]

I have a 2' breaker bar (1/2" drive). It probably just needs a good bit and some elbow grease.

 

Do I need penetrating oil? The rotors had been turned a few months ago, so what's sticking is more likely to be threadlocker than rust.

 

These look like what I need, confirmation would be nice:

http://www.autozone.com/autozone/parts/Duralast-Brake-Caliper-Bolt-Guide-Pin/1999-GMC-Sierra-1500-2WD/_/N-jdwrrZ8knjf?itemIdentifier=426242_0_4222_

 

Since they are stocked at a local store I may just pick up 4 hex head pins and discard the torx pins.

[TimmyG]

If ita thread locker put heat on it and it will come right out

 

Sent from my ADR6400L using Tapatalk 2

[iminaquagmire]

Those look right for the GMT800 calipers. It says they are in the application on the website.

[Lv1G6He3V2]

This weekend we tried the other front caliper and rotor - no issues with the T-55 guide pins. In fact one seemed loose.

 

What gave us so much trouble was the 18mm bracket bolts. They came loose with a bit of effort, then halfway out they tightened and the wrench bent. I thought the threads were damaged until we saw some yellow/black loctite in the threads. We removed that junk, checked the threads, and used blue loctite when torquing them down.

 

Just one more wheel to go...