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GMT 900 brake upgrade

qreaigh

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I have read a lot of the post and I really haven't seen it mentioned. when I order the parts do I look for GMT900 front brakes for any 06 chevy or is there a specific model 06 truck I should look for.
 
??? A gmt900 is 2007 up trucks. So basically you are putting on 07 up brakes on your 06.
 
CarMech1969 said:
I guess this means we 2500 folk are SOL for this upgrade  :(

CarMech1969

I don't know if you read the other post about this mod, 2500s have 1500 front brake caliper on the rear and 2500/3500 on the front that have huge caliper pistons. I don't think increasing the size of the rotor to 13 inches is going to help a 2500. Plus all 2500 came with a 16 inch wheels so you can't go too big.
 
MS03 2500 said:
I don't know if you read the other post about this mod, 2500s have 1500 front brake caliper on the rear and 2500/3500 on the front that have huge caliper pistons. I don't think increasing the size of the rotor to 13 inches is going to help a 2500. Plus all 2500 came with a 16 inch wheels so you can't go too big.

So then, that means our brakes are already strong enough?
FYI, when I first got my Avalanche and was driving it home, I was surprised how well the brakes could stop a 7000 lb truck!!  :eek:
This in comparison with my '92 GMC Sierra.
Having 4 wheel discs sure makes a difference.

CarMech1969
 
MS03 2500 said:
I don't know if you read the other post about this mod, 2500s have 1500 front brake caliper on the rear and 2500/3500 on the front that have huge caliper pistons. I don't think increasing the size of the rotor to 13 inches is going to help a 2500. Plus all 2500 came with a 16 inch wheels so you can't go too big.

Not trying to thread jack but I have a question!

So i have 16' rims on my truck with 33' tires. I want to upgrade my front calipers but i dont want to buy new rims (i like more tire sidewall then rim), could i just upgrade to a 2500 front brake caliper?
 
I have not seen that done joker, but the rotors are the same size so with the caliper and bracket they should fit.

Carmech yes they can slow ya down quickly,  I  had to make a emergency stop on the freeway when 2 cars thought could occupy the same lane so into the wall they both went then they both bounced back on the freeway lane. I got close to the little car in front of me. But no complaints about the brakes just stand on them.
 
joker79507 said:
Not trying to thread jack but I have a question!

So i have 16' rims on my truck with 33' tires. I want to upgrade my front calipers but i dont want to buy new rims (i like more tire sidewall then rim), could i just upgrade to a 2500 front brake caliper?

No point unless the caliper is bigger with bigger pads. Otherwise you can have an issue with the rotors warping. My belief is that they upsized the brakes on the newer trucks because with the demise of  some of the rear wheel drive vehicles some police departments went to Tahoes and those would warp the caliper on a SINGLE panic stop at speeds over 100 mph. So it was common to need new rotors after a high speed pursuit. Thus the larger brakes allowing more heat dissipation and better stopping from higher speeds and less likely hood for warpage. There are other benefits as well and I don't know this as fact as why they upsized so take that with grain of salt. With that in mind though no upgrade in brakes without going to larger rotor will help with the heat dissipation. And I assure you that 16" rims will not work. 17" rims are tight...

 
I guess it's a good thing my 2500 won't go 100 MPH, lol

But the 2500 front calipers are bigger, but the rotors are the same diameter. Never had a warped rotor even when towing heavy loads.
 
for one panic stop the; BRaking is a function of:
PAD contact area
distance from axle centerline to center of pad area.
Friction material.
Rotor surface and material

For many stops like racing you want to to get rid of the heat with the above.

Reason GMT900 brakes work better is the larger diamter which means an increase in the distance from pad center to axle so a greater torque arm (like a longer wrench) this is the reason for the improvement.

IF pads are larger that helps too.

 
But are the pads bigger on the 2500 as well?

You can provide more clamping pressure against the rotor with a larger caliper but is the rotor thicker too?

If the 2500 rotor is still thicker worn out than the 1500 is new the caliper may not have enough travel regardless for a 1500 even if it will bolt up. Which at this point we don't know.

I heard the "had to replace" story from the guys that serviced the GRPD vehicles and heard the same story from some local departments when I asked to verify when I ran into officers that drove them too. Most of the drivers I talked to didn't really care for the tahoe other than it gave them room for their equipment.

Was a while ago obviously since that only applied to pre-2007 vehicles.

Rodney
 
OK here are the spec. atd785c is my rear and 1500 fronts.

atd784c is the 2500 fronts, so they are a 1.5 inch longer




REMEMBER THIS HAS NOT BEEN TRIED YET and I don't know if you can mount them
 

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You might need to check caliper brackets against each other to see if they line up as well.

Lots of "maybes" and "need to try" to get marginally better brakes at best if they work.

Strongly suggest going the route of going with 900 brakes and get larger wheels.

The difference in ride between 16 and 17 inch rims is negligible and will depend much more on the tire used that the rim size. Either tire will have LOTS of sidewall.  And if you still want more, well then look into lifting your truck and getting bigger tires... Will affect your final gear ratio but depends on the tire.

Rodney
 
You are correct Rodney the first step is to get a bracket and see if it aligns with bolt holes on the steering knuckle
 
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