brake question.....


  #1  
Old 12-13-06, 08:24 AM
M
Member
Thread Starter
Join Date: Dec 2006
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Question brake question.....

hello,

i have a gmc yukon 99 4x4 5.7

the rotors and pads are fine so are the drums and shoes. the problem is that if the truck has been sitting overnite or for a few hours. i can get in it pull forward and apply brakes and the front pads seem to grab very hard/quickly. i have checked the rear shoe adjustment and they are set to proper distance to the drums.
after the turck has been driven for a few mins and the brakes applied again they seem to work normal. i was wondering it anyone many know if this sounds like a brake proportioning valve problem? the reason i think it may be the valve is because it comes and goes. as if it pumps up or gains pressure when the brakes work as normal. i bought this yukon new and keep it well serviced, but this is a first for me with this type of issue.

thanks
maXX
 
  #2  
Old 12-13-06, 02:20 PM
HotxxxxxxxOKC's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Jul 2006
Location: USA
Posts: 7,754
Upvotes: 0
Received 1 Upvote on 1 Post
Completely normal. All vehicles do this. Both my cars, and my older trucks did this. It does this because the rotors and pads are cool, providing stiffer breaking.

Both our diesel trucks at work are real bad with this, they were Chevy 3500's. Aspecially if it were cold and/or rainy. You tap the brakes, it feels like it's locking up.


I would says this is normal in your case as well. This doesn't happen after you driven it a few minutes, does it?
 
  #3  
Old 12-13-06, 02:45 PM
G
Member
Join Date: Jun 2006
Location: United States
Posts: 2,296
Upvotes: 0
Received 31 Upvotes on 29 Posts
I think it has something to do with the rotors getting warm/hot and moisture and in winter weather a little salt, the rotors after being used are raw metal and when they cool start to rust(very, very slightly) and it creates a film on the rotor, when the brakes are first applied it has to wipe the film from the rotors and is creating your sensation. It seems to be more prevelant on vechicles that have had the rotors replaced/turned and new pads, most of which have a metalic impregnation. Have a nice day. Geo
 
  #4  
Old 12-16-06, 03:46 AM
M
Member
Thread Starter
Join Date: Dec 2006
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Lightbulb

correct it only does this when its cold or has been sitting for while. after driving a while it does seam to go away. its just its never done this before. i just dont understand how it could start all of the sudden if it where rotor or pad releated. im using the same pads/rotors ive used sence i bought the yukon new.

thanks for everyones help
maXX
 
  #5  
Old 12-16-06, 05:32 AM
M
Member
Join Date: Nov 2006
Location: Jersey
Posts: 491
Upvotes: 0
Received 0 Upvotes on 0 Posts
I agree with HotinOKC.
I was going to ask do you have alot of dew of fog in the morning where you live as this can cause that grabbing sensation first thing in the morning.
I've experience this on all of the vehicles I've had, chev,ford,chrysler...

I'ts funny, if your not expecting it you can lose your coffee cup at the first stop sign.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: