@
cwilliams563
the larger rotors do help with brake fade and like what firebird says the larger diameter gives you more torque to slow the truck down faster. 4th gen Sport/Limited are the same diameter as 5th gen, but they're narrower by almost 4mm and the pistons in the calipers are smaller.
I forgot where I found this but it's relevant to this converstation:
4runner brake size
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The 5th Gen calipers have shown less issues with seizing than the 4th gen calipers have. (my front left caliper seized which prompted this thread)
The 5th Gen front and rear caliper pistons are (2.5mm-3mm) larger than the 4th gens (not sure if this is compared to 13WH, 13WG or both)
The 5th Gen front rotors are 4mm thicker than the 4th Gen rotors. (this extra thickness helps with heat dissipation and warping)
The 5th Gen front rotors are the same diameter as the 4th Gen Sport (338mm or 13.307") (SR5 has 319.024mm or 12.56")
5th Gen Front Rotors:
Nominal Thickness: 31.8mm (1.25")
Minimum Thickness: 29mm (1.14")
4th Gen Front Rotors:
Nominal Rotor Thickness: 27.94mm (1.1")
Minimum Rotor Thickness: 25.908mm (1.02")
It is possible to use the larger (Sport) 4th Gen rotors with 5th Gen calipers...
The pistons in the calipers will over extend when the pads get warn down if you use the 4th Gen front rotors with the 5th Gen calipers.
It is highly recommended to upgrade the rotors too. It is even less recommended to use the SR5 rotors with the 5th Gen calipers
because of the smaller rotor diameter in addition to them being thinner.
5th Gen Rear Rotors:
Nominal Thickness: 18.034mm (0.71")
Minimum Thickness: 16.002mm (0.63")
Outside Diameter: 312.166mm (12.29")
4th Gen Rear Rotors:
Nominal Rotor Thickness: 18.034mm (0.71")
Minimum Rotor Thickness: 16.002mm (0.63")
Outside Diameter: 311.912mm (12.28")