Gm Brembo upgrade added...sluggish acceleration and much lower mpg.

[Chad G 1979]

If your ebrake is dragging that could be the cause of the issue. It is possible that it had gotten out of whack when they did the brake change. Hopefully the driving you've done hasnt done much wear on the ebrake system, but if so, then the dealer who did the work can fix that as well. For free ofcourse if they caused the damage/issue to start with.

 

[DuraYuk]

B.S. i added Baer erradispeed brakes to all 4 corners of mine those are way more than a lb extra each, did not change even a fraction of mpg, neither does adding 500+ lbs of people and gear. what does change it? pushing the big pedal.

Its not BS it's physics lol. Weight needs more energy to move. It's really that simple.

Rotational mass is a huge deal. Its one of the most 'felt' things there is. Why do you think sports car have such light wheels?

It absolutely does make a difference. Still it's hard to diagnose from the internet. If the brakes are dragging they will get hot. Piping hot if it's dragging as much as he says they are. You could feel the heat with your hand or a infared thermometer.

Be interesting to see what it actually ends up being.

 

[Doubeleive]

Its not BS it's physics lol. Weight needs more energy to move. It's really that simple.

Rotational mass is a huge deal. Its one of the most 'felt' things there is. Why do you think sports car have such light wheels?

It absolutely does make a difference. Still it's hard to diagnose from the internet. If the brakes are dragging they will get hot. Piping hot if it's dragging as much as he says they are. You could feel the heat with your hand or a infared thermometer.

Be interesting to see what it actually ends up being.

yes it will, but it won't be the brakes
I bet it's the big pedal, my wife can jump in mine and be getting 2-3 mpg more than me and it's not the weight, it's the way she drives versus how I drive
I bet the dealer won't find any issue either if the OP even bothers to ever follow up
these aren't F! car's with carbon fiber parts, they can tow and haul thousands of pounds and the mpg is directly affected by how you drive in fact it's the biggest factor more than anything else. I can make my 12 get 7.5 or 14 on purpose and I can make my 18 silverado get 7.5 or 25 (it's much more efficient when coaxed, my best on it is 32mpg).
if I am wrong so be it, but the wheels spun free according to the dealer and nobody else has reported having lost mpg from a brake upgrade.

 

[Rocket Man]

If you guys think adding even a hundred extra pounds in brakes will affect your mpg by 6-8 mpg you’re delusional. Otherwise nobody would be putting BBK kits on. And then add the extra 100 lbs from running big rims and now you’re getting what, 12mpg less because you’re ballin on 26’s with big brakes? Come on man you’re killin me.

 

[WalleyeMikeIII]

I’d check the tire pressure! Much more likely to affect the economy than new rotors.

The physics of the brake weight requiring more power doesn’t hold for me, because once you get the additional mass spinning, the added angular momentum would tend to keep you moving (vs reduce your economy). Think about it, let’s say you added 50lbs per wheel; that’s 200lbs…same as a passenger getting in with you. Do you see that much Econ redux when your buddy comes along fishing??

 

[WalleyeMikeIII]

I’d check the tire pressure! Much more likely to affect the economy than new rotors.

The physics of the brake weight requiring more power doesn’t hold for me, because once you get the additional mass spinning, the added angular momentum would tend to keep you moving (vs reduce your economy). Think about it, let’s say you added 50lbs per wheel; that’s 200lbs…same as a passenger getting in with you. Do you see that much Econ redux when your buddy comes along fishing??

NVM, I see above he adjusted that. E-brake or stuck caliper…gotta be; but then would see heat rise I would think…

 

[B-train]

I do recall some guys complaining about some sort of brake upgrade and it ended up being stuck/sticky calipers. I don't know the post it was in though.

As stated above, basic driving with before, during, and after temps at the hat section (dull area) of the rotors should tell you what you need to know. If suspecting the e-brake, hit the splash shield by the axle after a drive while using little to no brakes and see if it's warm or hot.

Have you tried applying the parking brake to see if it operates correctly? Does it stop the truck? Does it fully engage and disengage? Easy enough to test in a parking lot or back road.

Go for a drive and then jack up each axle immediately when home and spin tires by hand. Listen for noises and see how much force it takes. You could also do a before test with everything cold and see how it feels. None of these things wi be "quantitative " but they can help move in a direction of correction.

Process of elimination......

 

[Thrust]

Look at the Brembo retention springs and guide pins. Did the technician install the spring correctly? Are any of the pins bent, causing the brake to drag?
If you really do have a dragging brake pad you should be able to feel the heat by touching the wheel after a short drive, or drive enough to eventually smell the piston boots (hot rubber).

 

[DuraYuk]

If you guys think adding even a hundred extra pounds in brakes will affect your mpg by 6-8 mpg you’re delusional. Otherwise nobody would be putting BBK kits on. And then add the extra 100 lbs from running big rims and now you’re getting what, 12mpg less because you’re ballin on 26’s with big brakes? Come on man you’re killin me.

It's basic physics. Heres a quick simple read to help you over come your lack of understanding.
https://www.linkedin.com/pulse/what...orted,you're considering making modifications.

Big brakes will negatively affect mpg. OP is having a drastic reduction which could be a combination of factors. But to dismiss the rotational mass all together is short sighted.

 

[DuraYuk]

I’d check the tire pressure! Much more likely to affect the economy than new rotors.

The physics of the brake weight requiring more power doesn’t hold for me, because once you get the additional mass spinning, the added angular momentum would tend to keep you moving (vs reduce your economy). Think about it, let’s say you added 50lbs per wheel; that’s 200lbs…same as a passenger getting in with you. Do you see that much Econ redux when your buddy comes along fishing??

Can you please read this: https://www.linkedin.com/pulse/what...orted,you're considering making modifications.

If OP would respond back we may get a better idea of what's happening. Probably a combination of things.