My Tundra spun out of control due to the integrated brake controller. The electric brake setting did nothing even at the highest setting (and after firmware update) so dealer said to put it on electric/hydraulic. Contrary to what the dealer says this setting does not give proportional braking, all or nothing. Brakes locked on a slippery road and truck and trailer spun out of control. This has been a problem since new and have tested it on 5 different trailers. Toyota says it meets their design specs. Unfortunately, their specs do not turn on proportional braking on the trailer. Dealer said others have the same problem and the only way to fix it is to add an aftermarket controller, $550. Toyota says to do so voids the warranty on the truck. Double bind since I have a multi-year warranty.

. Integrated brake controller (ibc) on a 2016 Toyota Tundra fails to adequately stop a trailer fitted with electronic drum brakes. When the brake controller is in the electric brake mode, I get very little braking with the ibc maxed at level 10 on the gain control. I can manually stop the trailer using the manual squeeze levers and the brakes stop the trailer and truck, but provides very little braking when using the brake pedal. The trailer pushes the truck creating a very dangerous situation. If I put the brake controller in the electric over hydraulic brake mode, the brakes work by the brake pedal but grab instantly at only a gain level of (1.5). The trailer brakes have been tested and work as expected with an aftermarket brake controller. Toyota's ibc, as noted by several other owners, on many websites are not performing as expected when towing a trailer. If road surfaces are wet or icy the truck breaks would have little chance to stop a loaded trailer at max capacity.