hi all, i have a couple of things i need help with if poss. 1st problem is n/s/f brakes squeel sometimes after sudden braking this noise goes after i reach speeds over 40mph, also i have a clunking noise under front of car usually when going over a rougher road. also im doing a oil change etc next week as im wanting to go for a stage 1 remap in a few weeks but wanted to know if i can run an engine flush through it to clean out all the muck and do i have to remove the sump? as i have heard mixed reviews of sumps cracking and whether it is necessary or not etc. thanks.