Brains Trust 2 Issues with Jeep Cherokee

[Methamon]

Hi All

1st Issue Coming down Cunningham Gap from Warwick towing caravan brakes failed Brakes went flat to floor seem very had to stop the jeep, could pump up and brake again severe brake smell Once cooled down they work but braking feels weird like i am fighting the brake pedal, hard to describe

2nd issue being 36 degree day turned in aircon and car started to overheat went to 3/4 temp and the Jeep has never gone past half. Pulled over and let it rest turned off aircon all ok jeep made it back to brisbane no problem temp stayed at half. Would this be the compressor?
I am going to book it in at local garage but would like opinions
Thanks

[glend]

Ok, my opinions.
BTW, which model is it, petrol or CRD?
Brake issue. Get a brake specialist to look at it. You have not said what kind of brakes you have on the caravan, and that is a factor. Important do they work. If it was a car alone in that situation I would suggest looking at the fluid level and the master cylinder - these are not new vehicle and I have no idea how well maintained it is.
Over heating. I am guessing this happened when towing? Regardless, what your seeing is the engine management system shutting down things to try and reduce the heat build up. When it gets up above 1/2 it starts taking steps, and at 3/4 yes it will shut down AC. It's not a compressor problem imho, but simply the system trying to shed heat load. The AC condenser dumps a lot of heat into the air in front of the radiator, this drives up the engine temperature. These comments apply to the CRD primarily. Transmission temp can be a factor as well but you get a different response.
These are many past threads here about heat management and how the engine responds, you could use the Search function to find them if your interested.

[dhula]

Brakes:
Sounds like you suffered brake fade and may have boiled the brake fluid as well. I've seen car/4wd with nothing on the back suffer similar coming down the gap.
Riding the brakes all the time, even lightly, prevents them cooling down so you need to use gears when coming down long/steep hills (that is why you always see "Trucks/Buses use low gear" signs) and moderate you use of the middle pedal.

How heavy is the van
Has it got functioning brakes
What gear where you in
How fast were you going
How much where you using the brakes

Overheating:
Where you towing when the KJ overheated?
Being only 36 degrees and putting the AC on sounds like there is something wrong with the cooling system in your KJ. I'd suggest changing the coolant (and a good clean at the same time), make sure the fan clutch is working properly (IMHO change it, don't faf around) and make sure there is nothing blocking airflow through the rad.
I drove through the heat wave in SA (49 degrees showing on the outside temp readout thing) a couple of months ago with the AC blasting as well as it could and my KJ never went over half, the elec fan was running as hard as it could and never switched off though

[Methamon]

Thanks

I was in second gear (Auto) however stuck behind a semi Caravan was about 1.5 tonne and had electric brakes which were set to high for decent however the jeep still wanted to go faster than 40km still and i didnt want to go to first as i thought this would be extreme revving. I have a 3.7L petrol. Going to mechanic tomorrow so we will see how it goes. I was feathering the brakes a bit so my fault

[palla]

Any news on this? Im interested in the findings.