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2002 gmc envoy_slt
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Discussion Starter · #1 ·
Just had all four rotors and pads changed within the past year on my 2002 slt 4wd. I am noticing that my brakes have no "bite" to them. When I try and stop, they just slow the truck down. I have to push the pedal really hard to get them to stop.(pedal pressure is fine, not spongy) It feels like my brake pads are made of wood...if that makes any sense!

Dealer says that this is normal for "aftermarket" pads...I thought they were Delco as the dealer was the one who installed them. They cleaned and machined my brand new rotors and it is still the same. They also checked the master cylinder and said all was fine with brake fluid.

I have no idea what to do next. I do not feel safe anymore, especially when pulling my boat. Help!!

Thanks!
 

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2004 gmc
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Have you been talking with the service manager? Try to get his manager to take it for a test drive and see if he agrees you should be taking a boat out with your concerns and HIS LIABILITY.

But welcome! What are you doing taking the truck to a dealer for something as simple as brakes? Worried about being cheated by an independent mechanic? Seems like the dealer must have hired their castoffs!
 

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2005 chevy trailblazer_ls_ext
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:iagree: with what Roadie said - but one more thing to consider. New pads often take a while to "break in" or seat properly.
I've done LOTS of brake jobs over the years and I've noticed that after a few hundred miles the pedal "feels" a lot firmer and stops better.

Also, some manufacturers recommend a "bedding" in process which amounts to several hard stops from about 30 MPH to 10 MPH or so.
http://www.tirerack.com/brakes/tech/techpage.jsp?techid=85

:eek: OOPS - I just reread your post and you did say "within the past year". My bad. I originally thought you just had them done.

But - there is a difference between various brake pads and rotors. Did your invoice state the part number they used? Of course we all know a dealership would never lie to a customer and use cheaper parts than they were charged for! :D

Like Roadie said - have them take it for a test drive and/or ask to test drive a similar year vehicle for comparison.
 

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2003 chevy trailblazer_ls
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well, with it being a 2002---
I would bleed the brakes--- its very possible that the brake fluid has absorbed moisture.
Moisture doesnt compress like brake fluid... that could cause the sucky braking.

I would get on the floor- and bleed the brakes---
Take a turkey baster- and remove most of the old fluid---
refill with fresh fluid (should be clear)
at each tire--- pump and bleed-till the fluid comes out clear(er).
Always taking note that the reservoir does not get low or else you suck in air.
But youll notice when the fluid stops coming out dark- and eventually flows semi clear...
Repeat with the rest of the corners.
Remember the farthest is done 1st.

If you dont want to do the bleed--- some shops use some machine to do a flush...
 

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2004 gmc
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Three more thoughts. Take another trailvoy for a test drive to compare. Worry that your brakes don't have enough power to cause slippage to trip the ABS system (try them on gravel). It could also be a weak power booster/collapsing vacuum hose.
 

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2004 trailblazer_lt
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Just had all four rotors and pads changed within the past year on my 2002 slt 4wd. I am noticing that my brakes have no "bite" to them. When I try and stop, they just slow the truck down. I have to push the pedal really hard to get them to stop.(pedal pressure is fine, not spongy) It feels like my brake pads are made of wood...if that makes any sense!

Dealer says that this is normal for "aftermarket" pads...I thought they were Delco as the dealer was the one who installed them. They cleaned and machined my brand new rotors and it is still the same. They also checked the master cylinder and said all was fine with brake fluid.

I have no idea what to do next. I do not feel safe anymore, especially when pulling my boat. Help!!

Thanks!
This statement leads me to believe the culprit is the power brake booster. I've seen cars go out of the shop with the vacuum hose unplugged from the booster that reacted the same way. A vacuum leak shouldn't be that hard to find though. The booster itself could have a leak, but it would have to be pretty big to cause that noticable of a loss of braking ability. I would take it (carefully) to a reputable brake shop and have it re-diagnosed. Then I would send the repair bill to the original shop (since they already had a second chance to find the problem) or demand a refund for the original bill. Take this seriously...faulty brakes are dangerous!
 

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2006 chevy trailblazer_lt
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There could be many things going on here, so it is hard to know the real cause of your perception.

That said, there are certainly differences in brake pads, and in how they feel. Different pads have different coefficients of friction, and yes, it does make a difference how they are broken in.

Further, some pads, like semi-metallic pads don't work as well cold as they do hot. Ever start out on a cold winter morning and have the feeling that your brakes aren't stopping as well as they should? If they are semi-metallic pads, they aren't. Full metallic pads are even worse!

If your problem is truly the pads, then buy a set of "performance" pads, like Hawk. They do "bite" better. But you will have more brake dust, they will have less bite when cold, and they will wear out your rotors faster in normal operation.

Our pads, at least on the newer Trailvoys, are ceramic. I suspect but don't know, that there are different grades of ceramics with different performance characteristics.

My own personal test of brakes and braking effectiveness is to find an empty road or parking lot and at about 35 mph jump on the brakes full force. If you can slide the wheels in non-abs cars, and activate the abs in cars so equipped, then the brakes will stop you in an emergency. You may need to use more pedal pressure (so your power booster may not be fully functional), but it is not the pads, rotors or calipers. If you can't lock up the wheels, then I would conclude that the pads are the cuplrit.

Now, if you are going to change to pads that are a different composition, then you should either use new rotors or have your rotors surfaced. Further, you should follow the Tire Rack or other recommendations on how to properly break in the new pads and rotors.

What most folks don't know is that it is not the brake pad pressing against the steel of the rotor that stops the vehicle. During break in there is a layer of pad material that transfers to the rotor, and so it is pad material rubbing against pad material that creates the friction. That's the reason for recommending new rotors or having your rotors cut.

Just my thoughts.
 

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2002 gmc envoy_slt
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Discussion Starter · #9 ·
Thanks for all of your replies. The truck is back at the dealer right now. They are putting OE pads on as they believe that is the problem. I will report back what happens.

Thanks
 

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2002 gmc envoy_slt
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Discussion Starter · #12 · (Edited)
Hi....

I have since sold the Envoy. It was the best vehicle I have ever owned but I love my new Grand Cherokee!

What I ended up doing is replacing all 4 rotors and brake pads with OEM GM pads and rotors...I think that the rotors were defective or I screwed them up towing my boat. I did all the work myself in my garage and it only took me a few hours. I have never changed brake pads or rotors before and I have no automotive mechanical experience! After replacing everything, all was perfect...good as new and I loved the truck again!

Good luck!
 
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