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Weak Brakes

yz2009

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jro909 Senior Enthusiast

jro909

Posted
Posted

i was having to pretty much stand on my brake pedal for quite awhile....and finally the dealer figured out my rear brakes were dragging...in the end they caught this after the rear pads and rotors were toast, needless to say after new brakes and rotors i got a little better braking but i still have to put some effort into it if its a quick brakeing high speed scenerio....in my opinion i think the drum brakes performed better in the gmt-800s

ChevyTech77 Senior Enthusiast

ChevyTech77

Posted
Posted

Never had an issue making a disc/disc GMT800 stop on a dime. You've got issues with the following,

Sticking caliper slide pin(s)

Excessive rust build up on the brake rotor(s)

Brake pads made of cardboard. (i.e. cheap-o replacements)

 

I would make sure ALL (all = front and rear) of the caliper pins are sliding like they should be.

Same goes for ALL of the brake pads in their guides in the caliper brackets.

Replace any severely rust pitted/flaking brake rotor with new.

Use a quality brake pad in ALL locations.

 

 

I have a 6400 GVW 1500 Silverado with a single piston rear caliper. Can I simply change to a 7200 GVW double piston caliper with matching larger rotor and pads. It looks like they will just bolt on, both setups are from the GM parts list. It looks like this will greatly increase the braking capacity of my poorly braking truck, possibly having to change the ABS computer setting

No change in abs systems but the master cylinder is for sure different along with, I believe, the brake booster as well. The calipers and rotors will install without issue. Rear brake flex hoses may be different as well, now that I think about it, but I doubt all of this will net you much of an improvement in stopping. Worse case scenario is the rear brakes will work TOO well with the truck unloaded and you'll be turning the dynamic rear brake balance system on all the time and it will just dump rear brake pressure off the calipers until the rear brakes stop locking up.

 

FYI, my '11 with the disc brake rear brake system (comes with the 6.2 or NHT package) has the exact same calipers, pads and rotors that the '99-'04 trucks had on them EXCEPT, my calipers have no inspection hole in them to check the pads/let all the dirt into the brake pads to cause excessive wear. It is rated to tow a 9400 lb trailer. Just fyi.

davebb Enthusiast

davebb

Posted
Posted
Never had an issue making a disc/disc GMT800 stop on a dime. You've got issues with the following,

Sticking caliper slide pin(s)

Excessive rust build up on the brake rotor(s)

Brake pads made of cardboard. (i.e. cheap-o replacements)

 

I would make sure ALL (all = front and rear) of the caliper pins are sliding like they should be.

Same goes for ALL of the brake pads in their guides in the caliper brackets.

Replace any severely rust pitted/flaking brake rotor with new.

Use a quality brake pad in ALL locations.

 

 

I have a 6400 GVW 1500 Silverado with a single piston rear caliper. Can I simply change to a 7200 GVW double piston caliper with matching larger rotor and pads. It looks like they will just bolt on, both setups are from the GM parts list. It looks like this will greatly increase the braking capacity of my poorly braking truck, possibly having to change the ABS computer setting

No change in abs systems but the master cylinder is for sure different along with, I believe, the brake booster as well. The calipers and rotors will install without issue. Rear brake flex hoses may be different as well, now that I think about it, but I doubt all of this will net you much of an improvement in stopping. Worse case scenario is the rear brakes will work TOO well with the truck unloaded and you'll be turning the dynamic rear brake balance system on all the time and it will just dump rear brake pressure off the calipers until the rear brakes stop locking up.

 

FYI, my '11 with the disc brake rear brake system (comes with the 6.2 or NHT package) has the exact same calipers, pads and rotors that the '99-'04 trucks had on them EXCEPT, my calipers have no inspection hole in them to check the pads/let all the dirt into the brake pads to cause excessive wear. It is rated to tow a 9400 lb trailer. Just fyi.

 

  • 1 month later...
00Silverado4x4 Senior Enthusiast

00Silverado4x4

Posted
Posted
Ive got a 04' Sierra Extended Cab. I bought it with 60k miles and now has 100k. Ever since i bought it, it has had really weak brakes. Ive changed then and its made no difference. I did some searching and it seems like GM went back to rear drums in 05, and the 99-04 have poor braking because of the rear disc like mine has.

 

 

Discs give you better braking than drums. The drum change was due to the truck spitting up rocks/gravel which got wedged in the back rotors/pads. It only took a couple thousand miles on gravel roads to totally destroy the rear rotors. Beauty of disc brakes is they automatically adjust to get optimum braking, and since it's a flat to flat contact patch, they are consistant day in and day out. Drums need to be regularly adjusted or they don't work.

 

 

 

Had both types, both worked great for me. However I do need to point that yes drums do have to be adjusted but they are also automatic. The adjuster is designed to adjust anytime you back up & then brake.

http://www.frost.com/prod/servlet/market-insight-top.pag?docid=24463616

http://www.gm-trucks.com/forums/index.php?showtopic=122277&st=0

waumo1 Enthusiast

waumo1

Posted
Posted

If i ever need to do a quick stop i can push the petal all the way to the floor and the truck stops nowhere near quick enough.

 

 

Do you really mean the pedal goes all the way to the floor? If so, you have serious brake problems and need to get it addressed.

 

If you just mean you can stand on the pedal with as much force as you want and you get no additional braking, that is the way my 98 K1500 Ext cab was and one of the main reasons I got rid of it recently.

 

BTW - all flexible brake lines I have ever seen have steel braid inside, they are not just rubber. Cut one open some time to see.

ironhead3fan Enthusiast

ironhead3fan

Posted
Posted

My 1990 Chevrolet developed weak brakes. Turns out it was the right front caliper. Discovered that when 2 sets of right disc pads wore out prematurely.

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