08 Silverado - brake issue/ power issue

[colt20]

Not sure this is in the right category. I have just purchased an o08 Silverado. Two immediate issues were apparant compared to the one I traded in.
1. The rear brakes (I believe have an incrediblely loud squeal. the dealership has asked GM and they are going to just sand them. This started as I pulled out of the lot with 20 miles on it. Any ideas for the cause of this? It is very loud.

2. The bigger issue is that this truck seems to lack the pickup in power compared to the exact same one I traded in. It seems to have a higher overdrive gear. When you need power you basiclly have to put your foot into it and hit passing gear. The previous truck (also an 080) just got up and went with minimal effort. The dealership is going to check about a programming issue.

My question is does anyone have any suggestions or ideas that may help with this?

[scooter10572]

the issue with the brakes is most likely from the vehicle sitting on the lot and rust forming on rotors and drums,as far as the power issue you didnt say what year of truck you traded in?The new truck is drive by wire or putting it in laymens terms it has no throttle cable,if your previous truck wasnt at least an 03 then you had a cable and if it was a 4.3 v6 then you had a cable until the 07 model year.there is a definite difference in percieved feel from cable to electric throttle imo and this could be what you feel even though no problem exists.

[73ChevelleSS]

I would also agree that you need to drive the truck for a week or so before you start worrying about brake squeak.After that it should go away.The newer cars/trucks all use torque management in their PCM calibrations.You will definetly notice it more on the trucks.This was put into place to eliminate drive line clunk etc.You will notice it if you really nail the gas off the line.It feels like the truck is struggling to accelerate,but it completely normal.

[colt20]

The previous truck I owned was also an 08 identical to this one. The previous truck was seemed to have more instant power whereas this has to build. As far as the brakes go only getting worse as I have driven the truck for a week and a half and currently have 1800 miles on it. You can hear it from a block away. They are going to initially sand the brakes per GM. The previous truck also did not have this problem. I tend to trade every 5 to 6 months due to miles and resale. The previous truck had 28000 miles on it in just under 6 months. That truck was virtually perfect with the exception of the doors rubber stripping drying out more or less and thus causing creaking. The dealer also had no cure but we found a prevention. lubing it occassionally seemed to help.

I feel the brakes will be cured however this power change has me annoyed due to the other truck being great.

[colt20]

An update
1. The brakes were sanded and they still squeal just not as bad-as expected. They will probbaly replace in 1000 miles

2. The power issue seems worse and now it cant seem to naturally downshift unless you hit passing gear. and going up a hill it sees to have a light tremor and will not downshift naturally has to be forced and engine is bellowing like it is sucking in a lot of gas which i assume it is. Completely different that the last truck. Any ideas. The tremor makes me think transmission.

[TuffG929]

Is the rear-end gearing the same? What about the tranny (6spd vs. 4spd)?

[colt20]

It is identical went and verified on the sticker. Another example on this slwo down is slowing up for a car and after they are out of the way you give it gas and it down shifts naturally , not so here hangs in the gear or you have to hit passing gear.

[RB35SLT]

It could be the pads, but did the dealer check the pads?

[scooter10572]

Originally Posted by colt20

The previous truck I owned was also an 08 identical to this one. The previous truck was seemed to have more instant power whereas this has to build. As far as the brakes go only getting worse as I have driven the truck for a week and a half and currently have 1800 miles on it. You can hear it from a block away. They are going to initially sand the brakes per GM. The previous truck also did not have this problem. I tend to trade every 5 to 6 months due to miles and resale. The previous truck had 28000 miles on it in just under 6 months. That truck was virtually perfect with the exception of the doors rubber stripping drying out more or less and thus causing creaking. The dealer also had no cure but we found a prevention. lubing it occassionally seemed to help.

I feel the brakes will be cured however this power change has me annoyed due to the other truck being great.

I WOULD LIKE TO HAVE YOUR VIN NUMBERS FROM BOTH TRUCKS,TO CHECK AND SEE WHAT TRANS WAS IN OLD TRUCK,IF INDEED YOU HAVE A 6 SPEED AND HAD A 4 SPEED BEFORE THEN WHAT YOU MAYBE FEELING IS SHIFT STABILIZATION,ITS AN ALGORITHM IN THE PCM TO REDUCE SHIFT BUSYNESS AND IS ON IN ALL MODES AND CANNOT BE TURNED OFF.IF YOU LOOK AT YOUR RPO LABEL IN GLOVE BOX AND GIVE ME THE M CODES I CAN TELL YOU WHAT TRANS YOU HAVE.AS FAR AS THE BRAKES I PERSONALLY HAVE NOT RAN INTO THIS PROBLEM.IF YOU HAVE A 1/2 TON THEN YOU SHOULD HAVE A FOUR SPEED IN BOTH BUT I DID HEAR THE POSSIBILITY OF THEM PUTTING 6L80S IN 1/2 TONS TOO.ALSO THERE WAS A RUNNING CHANGE ON MID YEAR 08 TRUCKS TOO THE FRONT PADS THAT IS SUPPOSED TO HELP WITH NOISE BUT APPARENTLY ISNT INTERCHANGEABLE WITH OLDER TRUCKS.ANOTHER THING COULD BE THIS TRUCK HAS ACTIVE FUEL MANAGEMENT OR CYLINDER DEACTIVATION AND THE OTHER DID NOT

[colt20]

Trucks are identical. As I have driven it more it seems the hang up is in second gear both dropping down and climbin through. the brakes were deterined to be in the rear. This is the lesser prob due to the dealer stating it is a prob. they will replace when I am ready.