I had a brake issue in my car as I mentioned in this question 7 months ago. After that, I did a complete repair to the brake system.
I found out that the one of the caliper bracket is not functioning correctly. So I replaced both front caliper brackets with new ones. Then I had some master cylinder issue so I replaced it with a new one as well. I also checked all the brake lines. Now everything is in perfect condition and brake works smoothly.
However the problem is again, it is generating more heat. To confirm this I bought a temperature gun and measured the temperature of all 4 wheels.
NOTE: The measurements were taken by pointing the temp gun to the lug nuts and center of the wheel.
Car is front wheel drive car with front disk brakes and rear drum brakes
Drive 5km with no passengers that has few downhills. Both front wheels recorded 90C heat. Both rear wheels showed 40C.
Then I drive back that 5km again. This time, front wheels recorded 75C heat and 35C rear wheels.
Drive about 40km (20km back and forth) with no passengers in a hill country road. This time no different it was around 80C in both front wheels and 40C in both rear wheels.
Drive down one of the steep downhill in my country with max passengers(5) in 3rd and 4th gears with the speed of 40 - 55kmph. ( I didn't used the clutch when braking so no it always drove in the gear. Usually vehicles go down 60 - 80kmph in this downhill)
This time I had to stop my vehicle after I drove down about 5kms as I started to smell the brakes burning and my brake paddle started to feel loose. When I check the heat, both front wheels shows, 280C and both rear wheels shows 40C.
I just stopped for about 5min and then started to drive down the hill in 2nd gear. After the downhill ended, I drove about 3 - 5km on flat road around 50kmph. Then checked the heat again. This time it came back to 90C. Then I drove about 200kms on flat roads without any issues.
On each of these tests, the rear wheels heat never reached above 45C.
Every time I asked this from my mechanics they say it is normal to front disks to get much hotter than the rear wheels, however I drives that road 1 - 2 times a month with full passengers but I never experienced any brake issues even with my faulty caliper brackets that tends to get sticky when get hotter.
I can confirm that calipers are working 100% fine now. Also my mechanics told me that there's no need to adjust the rear brakes ( drum brakes ) as they get adjusted automatically.
What could possible go wrong here ?